Very Heavy MSSM Higgs-Boson Production at the Linear Collider

Ultra-High-Performance Concrete:Research, Development andApplication in EuropeMichael Schmidt and Ekkehard FehlingSynopsis: One of the breakthroughs in concrete technology is ultra-high-performance concrete with a steel like compressive strength of up to 250 N/mm2 and a remarkable increase in durability compared even with high-performance concrete. In combination with steel fibres it is now possible to design sustainable filigree, lightweight concrete constructions with or even without additional reinforcement. Wide span girders, bridges, shells and high rise towers are ideal applications widening the range of concrete applications by far. In addition e.g. to some pedestrian bridges heavily trafficked road bridges has been build in France and in the Netherlands. Bridges are already under construction in Germany as well. A wide range of new concrete formulations has been developed to cover an increasing number of applications. Technical recommendations have recently been published in France and in Germany covering material as well as design aspects.The paper will report on the state of research and application of UHPC in Europe, on material and design aspects of UHPC and will present the state-of-the-art based on an International Symposium on UHPC held in Kassel in 2004.Keywords: ultra high performance concrete; raw materials; durability; design aspectsMichael Schmidtborn 1947, studied Civil Engineering 1967-1973 at the Technical University of Hanover (Germany), received doctoral degree in 1977 from TU Hanover.Research Engineer and Senior Specialist at the Research Institute of the German Cement Industry in Düsseldorf 1978-1989. Director of Research and Development of the HeidelbergCement Group 1989-1998. Since 1998 Independent Public Consultant and Court Expert for building materials and cement and gypsum industry in Germany, Europe and Asia. Since 1999 Professor, head of Building Materials Department and Director of Governmental Testing Institute at the University of Kassel.Ekkehard Fehlingborn 1959, studied Civil Engineering 1978 -1983 at the Technical University of Darmstadt (Germany), received doctoral degree in 1990 from TU Darmstadt.Since 1988 registered Consulting Engineer, since 1997 State licensed Checking Engineer and Professor of Structural Engineering, University of Kassel,Partner of IBB Fehling+Jungmann, Consulting Engineers, Kassel / Fulda (Germany)INTRODUCTIONWithin the last two decades amazing progress has been made in concrete technology. One of the breakthroughs is the development of ultra-high-performance concrete with a steel like compressive strength of up to 250 N/mm2 and a remarkable increase in durability compared even with high-performance concrete. In combination with a sufficiently high amount of steel fibers it is now possible to design sustainable filigree, lightweight concrete constructions without any additional reinforcement. In prestressed construction elements the prestressing forces may be increased significantly especially if high-strength steel is used. Long span girders, bridges and shells are ideal applications widening the range of concrete applications by far. First practical steps into the future of concrete constructions have already been done. In addition to the well known pedestrian bridge in Sherbrooke in Canada and in South Korea heavily used road bridges has been build or reconstructed in France and in the Netherlands. A long span footbridge is under construction in Germany and the construction of a road bridge used by traffic under severe climatic conditions with intensive salt attacks in winter will start this year to gain more practical experiences with the durability of UHPC.The growing store of knowledge about the material itself and about the adequate design of constructions with UHPC enabled a technical working groups in France to draw up first technical recommendations primarily focussing on the design (Resplendino 2004, SETRA-AFGC 2002). In Germany a state-of-the-art report has recently been published covering all material and design aspects (DAfStB UHPC 2003).That means that the concrete itself is steadily optimized and a wide range of new formulations are developed to cover the individual needs of an increasing number of different applications. This paper will report on the state of research and development on UHPC in Europe and about recent applications either already realized, under construction or under development.HISTORY OF DEVELOPMENT AND APPLICATIONSIn the 1960s concretes with an compressive strength of up to 800 N/mm2 has been developed and produced under specific laboratory conditions. They were compacted under high pressure and thermally treated. In the early 1980s the idea was born to develop fine grained concretes with a very dense and homogeneous cement matrix preventing the development of microcracks within the structure when being loaded. Because of the restricted grain size of less than 1 mm and of the high packing density due to the use of different inert or reactive mineral additions they were called “Reactive Powder Concretes (RPC)” (Bache 1981; Richard and Cheyrezy 1995). Meanwhile there existed a wider range of formulations and the term “Ultra-High-Performance Concrete” or – in short – UHPC was established worldwide for concretes with a minimum compressive strength of 150 N/mm2.The first commercial applications started around 1980, based on the development of so called D.S.P. mortars in Denmark (Buitelaar 2004). It was primarily used for special applications in the security industry – like vaults, strong rooms and protective defense constructions.First research and developments aiming at an application of UHPC in constructions started in about 1985. Since then different technical solutions were developed one after the other or parallelly: Heavily (conventionally) reinforced UHPC precast elements for bridge decks; in situ applications for the rehabilitation of deteriorated concrete bridges and industrial floors (Buitelaar 2004) ductile fiber reinforced fine grained “Reactive Powder Concrete” (RPC) like “Ductal” produced by Lafarge in France or Densit produced in Denmark (Acker and Behloul 2004). With or without additional “passive” reinforcement it is used for precast elements and other applications like offshore bucked foundations. In addition, coarse grained UHPC with artificial or natural high strength aggregates were developed e.g. for highly loaded columns and for extremely high-rise buildings (Schmidt et al. 2003). Nowadays an increasing range of formulations is available and can be adjusted to meet the specific requirements of an individual design, construction or architectural approach.Breakthroughs in application were the very first prestressed hybride pedestrian bridge at Sherbrooke in Canada in 1997, the replacement of steel parts of the cooling tower at Cattenom and two 20.50 and 22.50 m long road bridges used by cars and trucks at Bourg-lès-Valence in France build in 2001 (Hajar et al. 2004), see fig. 1.For these projects the UHPC was reinforced with about 2.5 to 3 Vol.-% of steel fibers of different shape. The bridges in Bourg-lès-Valence consists of five precast beams which are pre-tensioned. They were placed on site and then joined together with in-situ UHPC. Other footbridges with decks and/or other load bearing components made of fine grained, fiber reinforced UHPC exist in Seoul and in Japan (Acker and Behloul 2004).A spectacular example of architectural taking advantage of the special benefits of UHPC is the toll-gate of the Millau Viaduct in France, currently under construction. Fig. 2 shows the elegant roof “looking like an enormous twisted sheet of paper”, 98 m long and 28 m wide with a maximum thickness of 85 cm at the center (Resplendino 2004). The structure remembers an aircraft wing. It will be made of match-cast prefabricated 2 m wide segments connected by an internal longitudinal prestressing.In other European countries UHPC is gaining increasing interest as well. In Germany, asa result of an extensive research project financed by the government, technical criteria and measures have been already developed to use regionally available raw materials forfine or coarse grained UHPC, to reduce the cement content and to use fiber mixtures and noncorrosive high strength plastic fibers to control the strength and the ductility depending on the requirements given by an individual design and construction (Fehling et al. 2003; Bornemann et al. 2001; Schmidt et al. 2003; Bornemann and Faber 2004). As a first application, a hybrid bridge is under construction (Fehling et al. 2004) for pedestrian and bicycles with a length of about 135 m and a maximum span of 40 m consisting of precast prestessed chords and precast bridge deck elements made of UHPC with a maximum grain size of 2 mm using local materials. Fig. 3 shows an animation of the bridge, fig. 4 its cross section. The 4.50 x 2.00 x 0.08 m wide bridge deck elements are prestessed transversely. As an additional step of innovation, the load bearing UHPC-elements are glued together without any additional mechanical connection. This means a further step towards an economic material adequate construction technique for UHPC. Inspired by first applications in Canada, South Korea and Europe and by intensive research and development efforts at different universities and of the cement- and construction industry, the DAfStB draw up a state-of-the-art-report on Ultra-High-Performance Concrete (DAfStB UHPC 2003). The DAfStB is part of the German Standardization Organization DIN being responsible for all standards and technical requirements related to the production and application of concrete and giving the rules for the design of concrete structures.The German state-of-the-art-report covers the technical know-how and the experience with UHPC worldwide published. It covers nearly all applications that exist hitherto – primarily based on commercially available UHPC mixtures – the main principles and the characteristic behavior criteria, durability aspects and the resistance against fire. A second part report refers to the adequate design and construction of structures using UHPC. The report traditionally is a first step towards a reliable technical guideline and a latter standard for UHPC.In the following some of the material and design aspects covered by the German state-of-the-art-report and by the French design recommendations are presented in more detail.MATERIALSRaw materials and material structureBoth the high compressive strength and the improved durability of UHPC are based upon the same four principles- a very low water-cement-ratio of about 0.20 to 0.25 resulting in a very dense and strong structure of the hydration products and minimizing the capillary pores, which are ductile to prevent brittle failure and to be able to use more or less traditional design approaches against the transport of harmful gases and liquids into and through the concrete,- a high packing density especially of the fine grains in the binder matrix reducing thewater demand of the fresh mix and increasing the compressive strength – as well as the brittleness of the concrete,- the use of higher amounts of effective superplastizisers to adjust the workability and – if needed –- the use of steel or other fibers to increase the tension, the bending tension and theshear strength and to make the concrete sufficiently ductile.Fig. 5 shows the packing effect schematically. As a simplified example, fig. 6 shows how the packing density develops when two quartz powders of different fineness (Q 1 and Q 2) are mixed together in different amounts (Geisenhanslüke and Schmidt 2004a). Up to a ratio of about 30 % of the fine and 70% of the “coarse” powder the packing density – defined by the part by volume of particles per unit volume - increases from 48 to 54 Vol.-%. The finer particles by and by fill up the hollow space in between the coarser grains. At the same time, the viscosity of a lime prepared with the powder-mixes at a constant water/fines-ratio of 0.26 decreased from 7500 to less than 5000 mPa s. If the amount of fine particles is further increased beyond the maximum packing density, the rheology of the mix becomes suboptimal again.To optimize the packing density of UHPC, usually specified quartz powders are used.Table 1 shows typical compositions of fine and course grained UHPC developed andused in Germany, fig. 7 the optimized grain size distribution of mix M1Q in table 1 consisting of four different fines. The correlation between the packing density – characterized by the water/fines-ratio of the matrix w/F v – and the compressive strength of heat treated (90°C) and water cured Cylinders (150/300 mm) is shown in fig.8. It is obvious that the packing density not only affects the rheology but also the strength of UHPC as well: at nearly the same water-cement ratio of 0.20 the compressive strength increased by about 25 % when the w/F v-value decreased from 0.53 to 0.40 by adding an pre-calculated amount of another quartz filler with a specified fineness. And table 1 a fig. 8 show that the use of coarser grains help to reduce the cement content and contributes to the compressive strength as well. Further tests showed that autogenous shrinkage and creeping were significantly reduced. The effectiveness of the fibers was reduced as well. This disadvantage could be partly compensated for using longer and stiffer fibers with a length of 17 mm and a diameter of 0.25 mm (Bornemann and Faber 2004).Due to an European Directive, quartz fillers containing particles with a diameter of less than 5 micron are suspected to cause health problems. This led to intensive efforts to replace those particles by other mineral powders. Positive experiences have been gained with finely ground granulated blast furnace slag, the fine and glassy parts of ground or assorted fly ashes from stone coal power plants and with some high quality stone dusts e.g. produced from basalt. Ultra fine slag particles are even adequate to partly replace microsilica. Common limestone fillers are – as a rule – less beneficial. Research is done to further improve the rheological and the strength performance of UHPC by adding nanotubes (Kowald 2004).The optimization process can be based on both a theoretical and experimental approaches. Usually the procedure of Okamura (Okamura 1995) is used. In Germany the actual packing density of cements or other powders is tested using the fast and easy Puntke-test (Puntke 2002). A specimen of about 100 g of the powder is filled into a container and slightly compacted. Than water or – for tests on powder mixes containingcement - a non-reactive liquid of known density is added until the surface is just wet.The amount of liquid added is a measure for the hollow space and – indirectly – for the packing density.Testing is time consuming and expensive, especially if the existing information about the powders is lacking and the grain size optimization needs several steps of iteration. Therefore some mathematically based, computer aided calculation procedures have been developed to pre-calculate the best fitting powders and the amounts of each being adequate to reach a maximum packing density (Geisenhanslüke and Schmidt 2004a). Experiences have shown that the results of the existing calculation procedures do not reflect sufficiently the reality when powders of different grain size, grain size distribution, shape and roughness of the surface are mixed in different proportions. In an active research project these procedures are developed further considering the 3-dimensionality of the structure, the shape, the friction of the grains and the so called “particle handicap” schematically shown in figure 9. These effects hinder the individual grains to really reach their theoretical optimum position within the structure of the powder mix.Strength and deformation behaviorBasis of an adequate, economic and safe design of structures fully or even partly consisting of UHPC elements are reliable reference values characterizing the strength and the deformation behavior under static and dynamic loads. Fiber free fine or coarsely grained UHPC mixtures as shown in table 1are characterized by both, a high compressive strength in between 150 and 250 N/mm2 primarily depending on the water-cement ratio, the volumetric water-to-fines ratio w/F v = w/Σ Vol.(cement+silica+fillers) of the matrix and the grain size of the aggregates as well as a linear elastic deformation up to about 95% of the fracture load. That means UHPC without fibers is a glass like brittle material with a comparatively high modulus of elasticity of 50.000 to 70.000 N/mm2. The typical tension strength of the pure matrix is about 8 N/mm2.Using steel or other adequate fibers with a sufficiently high modulus of elasticity of more than about 45.000 N/mm2, the compressive strength keeps constant or increases slightly while the tension, the bending tension and the shear strength as well as the ductility are significantly improved. As an example, table 2 (Bornemann et al. 2001; Fehling and Bunje 2004) shows that the bending tension strength of concrete prisms 40/40/160 mm made of fine grained UHPC (Mix M1Q) with 2.5 Vol-% of short steel fibers (length 6 to 9 mm, diameter 0.15 mm) was up to 36N/mm2, that of beams 150/150/700 mm made from the same concrete but without steel fibers was 22 N/mm2 only.That means if the bending strength of fibered UHPC is introduced into the design of structures it has to be considered that the bending strength primarily depends on the kind and the amount of fibers used, but the orientation and the distribution of the fibers within the matrix and the shape of the specimen used and of the structural element produced with the specific concrete may have a significant influence as well. As a rule, the spread of test results of a specific mixture exceeds that of UHPC mixtures without fibers significantly. Therefore the number of tests done to characterize one specific mix has to be increased to allow a calculation based on the standard deviation (…Characteristic Strength“, 5% fractile). In some active research projects these aspects are furtherinvestigated. Until sufficient knowledge has been gathered and measures have beendeveloped in order to influence e.g. the fiber orientation by the production process, elements of the designed shape should be placed and tested to validate the theoreticallyassumed design criteria.The same aspects have to be considered regarding the ductility of UHPC. The “amount”of ductility being necessary to fit the needs depends on the individual design andconstruction approach: if the UHPC is assigned for bearing the full tension and bending tension loads without any additional active or passive reinforcement – like in some of the applications e.g. of Ductal – the fiber content has to be sufficiently high to prevent sudden failure even if cracks due to uncalculating stresses and strains appearing locally . In those cases a fiber content of about 2.5 to 3 Vol.-% may give a satisfying compromise regarding workability of the fresh concrete, bending strength and ductility. For other applications, a reduced amount of e.g. 1 Vol.-% of fibers may satisfy the needs, e.g. if slabs, girders or other elements made from UHPC are fully pre-stressed and/or have a passive reinforcement. The fibers are some kind of “transportation reinforcement” and/or allow to utilize the high compressive strength more efficiently due to a higher safety margin to failure. As explained later a combination of passive reinforcement and fibers allow the shear reinforcement of beams to be omitted under bending loads. And in some cases UHPC may be applied even without fibers, e.g. for highly loaded columns or framework constructions consisting of ductile steel pipes filled with UHPC (Tue, Schneider, and Schenk 2004).In Fig. 10 the effectiveness of steel fibers, high strength non-corrosive Polyvinyl fibersand a mixture of both, a so called “fiber cocktail” is shown (Bornemann and Faber 2004). Mixes consisting of steel and other suitable fibers of different kind, length and diameter may fulfill the individual needs of a construction more effective by and more economically than fibers of one uniform type.DurabilityThe improved resistance of UHPC to all kinds of harmful gases and liquids, to chloride and frost or freezing and thawing attacks is related to the improved density both of the grain structure of the matrix and the much denser contact zone between the matrix and the (coarser) aggregates as well as by the denser structure of the hydration products. Fig.11 gives an impression of the dense structure.The porosity of UHPC is characterized by the absence of capillary pores, as one can see from the pore size distribution shown in fig. 12 tested by mercury intrusion. As a result, the extremely high resistance e.g. to chloride diffusion is shown in fig. 13. The resistance to attacks by freezing and salting are significantly improved even when compared with High Performance Concrete, see fig. 14.In table 3 some characteristic durability indicators are given based on different sources (Schmidt et al. 2003, Teichmann and Schmidt 2004; Resplendino 2004;)DESIGN ASPECTSAs a rule, the design of concrete structures has to be based on reliable but simplified material reference values, e.g. for the strength and the deformation behavior. For ordinary concrete those approaches are given in the relevant standards. For UHPC two similar approaches have been developed, one established by AFGC/SETRA in France in 2002 (SETRA-AFCG 2002) and one as part of the state-of-the-art report of the DAfStB in Germany in 2003 (DAfStB UHPC 2003). They both consider the fact, that as a rule the material properties of fiber reinforced UHPC show a significant higher deviation due to an inhomogenious distibution and orientation of the fibres in the matrix (Bernier and Behloul 1996).The French recommendations consist of three parts:– the first part gives specifications on the mechanical performance to be obtained and recommendations for characterizing UHPC including checks of finished products and of the concrete being produced,– the second part deals with the design and analysis of structures made with fibre reinforced, non-prestressed and/or non-reinforced UHPC-elements and– a third part dealing with the durability of UHPC.An important part deals with the behavior of fiber containing UHPC under tensile loading. As fig. 15 (Resplendino 2004; SETRA-AFCG) shows, the stress-strain relation is characterized by an elastic stage limited by the tensile strength of the cement matrix f tj and a post cracking stage characterized by the tensile strength of the composite material reached by fiber action.Using characterization tests depending on the type of structure studied (thin or thick slabs, beams, shells) and on the kind of load (direct or flexural tensile) the recommendations give the transfer factors to come from the test results to an “intrinsic” curve for tensile behavior independent of the size of the specimen and the kind of test used. In addition, a reduction factor is given to take into account the effect placement methods has on the real strength values to be obtained in a specific structural element. The French design methods proposed are in accordance with the French codes for pre-stressed or reinforced concrete BAEL 91 and BPEL 91 based on semi-probabilistic limit state values. Supplementary to the design codes the recommendations contain specificities concerning UHPC like the strength provided by fibers which allows the design of structures without any conventional reinforcement.For normal stress verification, the French recommendations use the AFREM-BFM method which concerns fiber concrete, and use a stress-crack width constitutive law σ = f(w). Moreover the characteristic length l c is introduced, to go from crack width w to strain ε:ε = f tj / E ij + w/ I c,The value of I c depends on the sections area. The analysis for standard sections is based on the assumptions that plane sections remain plane and the concrete behavior law follows fig. 16. The limit stresses at the SLS are the same as for a reinforced orprestressed structure: 0.3 mm for normal cracking, 0.2 mm for detrimental and 0.1 mm for highly detrimental cracking. For calculation of the Serviceability Limit State (SLS), a somewhat more simplified stress strain relationship as shown in Fig. 17 may be used according to the recommendations given by (DAfStb UHPC 2003).The German report describes a standard test procedure as shown in fig. 18 to evaluate the load-deformation behavior of UHPC under bending loads in order to determine a stress strain relationship.Fig. 19 shows the result of such a test. To transform it into a stress-strain relation, the stresses at a crack width of 0.5 and 3.5 mm are being considered.Fig. 20 shows the stress-strain curves calculated according to this proposal. The stresses at the significant points of the curve are determined from the equationsσ2.0 – 3.5 ‰ = f ctk0.5 • 0.37 σ25‰ = β ٠f ctk3,5.The factor β as well as the factor 0.37 have been established by recalculating test results. As for ordinary concrete, the factor β depends on the relation f ctk,3.5 / f ctk,0.5. It can be taken from fig. 21.Normally a strain limit of 25‰ is adequate. But re-calculations of test results already showed that for a ratio f 3.5 / f 0.5 < 0,5 the design may fall short of the necessary safety margin. In fig. 21 the reduced strain for f 3.5/f 0.5 < - 0.5 is characterized by the marked curve. For the design in the Ultimate Limit State, the stress strain law according to DIN 1045-1 is proposed. It is defined by the following equation (1):c c20≥ε≥ε (1) The exponent n in Eq. 1 can be taken from table 4. This enables a transition to the rules for High Strength Concrete (HSC/HPC). For UHPC 210 and higher strength classes, hence, a linear relationship results. Furthermore, for UHPC without fibers or insufficient confinement,εc2 = εc2u shall be assumed in order to account for the brittleness in such cases. The design value of the compressive strength follows Eq. 2.'85,0c c ck cd f f γγ⋅⋅= (2)withc γpartial safety coefficient according to table 2 in DIN 1045-1 'c γadditional partial safety factor taking into account the sensibility for deviationsThe strain at the maximum stress can be assumed to be 2,2‰ starting with strength classC 100/115 acc. to EN 206. For the special permit required in Germany for structures built of new materials, different values may be proposed by the obligatory expertise. For UHPC with fibers or sufficient confinement, a plastic branch until the strain fc2u ε can be used in order to account for the improved ductility. The value of f c2u ε can be determined in such a way that the capacity in bending is adjusted to the bending capacity obtained from a stress strain law with a descending branch and assuming yielding of steel in the tension zone. However, since the influence of the descending branch of the stress strain relationship is of minor importance, the additional strain (length of the horizontal branch in the stress strain diagram) can be assumed to be quasi linear.Shear and TorsionIn order to determine the reinforcement possibly required for shear loading, the resistance due to the concrete, the shear reinforcement (e.g. stirrups) and the fibers can be added according to the SETRA–AFGC regulations:V u = V Rb + V a + V f(3) with: V Rb = shear resistance of concrete section V a= shear resistance to discrete reinforcementV f = shear resistance due to fibers (4)with:σpKw lim = max(w u ; 0,3 mm), where w u = l c ⋅ εu and l c ... characteristic length σ(w) = characteristic post cracking tensile resistance for crack width w (according to tests)S = area of fiber action:S = 0,9 b 0 ⋅ d bzw. b 0 ⋅ z for rectangular and T-shape sectionsS = 0,8 ⋅ (0,9 d)2 bzw. 0,8 z 2 for circular sectionsγbf= particular safety coefficient for fiber concrete in tension βu = angle of compression struts。

a rXiv:h ep-ph/952267v11Fe b1995BUHEP 95-3hep-ph/9502267February 9,1995The profile of a nonstandard Higgs boson at the LHC Dimitris Kominis ∗and Vassilis Koulovassilopoulos †Boston University,Physics Department,590Commonwealth Avenue,Boston,MA 02215USA ABSTRACT In a wide class of extensions of the Standard Model there is a scalar resonance with the quantum numbers of the usual Higgs boson but with different couplings to fermions and gauge ing an effective Lagrangian description,we examine the phe-nomenology of such a generic nonstandard Higgs boson at the LHC.In particular,wedetermine the circumstances under which such a particle can be observed in its ZZ decay mode and distinguished from the Higgs boson of the Standard Model.We briefly comment on the energy scale effectively probed at the LHC,if the nonstandard nature of an observed Higgs particle can be asserted.1IntroductionThe operation of the next generation of high-energy colliders(such as the LHC,LEP-II, NLC)within the coming decade is expected to bring us closer to an understanding of the mechanism of electroweak symmetry breaking.The minimal Standard Model(SM) is the simplest possibility,but its confirmation requires the discovery of a neutral scalar particle,the Higgs boson,with properties completely specified once given its mass.In the SM this is an undetermined parameter,and so far direct searches have set a lower limit of about60GeV[1].An upper bound of approximately1TeV has been suggested on the basis of“triviality”[2],and the validity of the perturbation expansion[3],which makes it likely that,if the SM Higgs boson exists,it will be discovered at the next generation colliders.However,it is widely believed[2,4]that the SM,despite its experimental success,can not be complete and that new physics,beyond the SM,should arise at somefinite energy scaleΛ.IfΛis very large,then the low-energy theory would look like the SM,while if Λis low(such as a few TeV),then deviations should be expected and the properties of a Higgs-like resonance(if present)could differ substantially from those predicted in the context of the SM.A resonance lighter than other massive degrees of freedom that shares the quantum numbers of the SM Higgs boson but couples to the electroweak gauge bosons and to fermions with nonstandard strength has been generically called a“Nonstandard Higgs”boson[5,6].Such an object is featured in a variety of models of electroweak symmetry breaking; namely,some models with dynamical symmetry breaking,such as Composite Higgs mod-els[7,8,9,10,6]and“top-condensate”models[11],as well as linear models with many fundamental scalars in which a mass gap exists between a light scalar-isoscalar(under custodial isospin)particle and all other resonances.If these models describe electroweak symmetry breaking,the isoscalar resonance presumably will be thefirst to be discov-ered in a collider experiment.It is not clear a priori,however,whether its nonstandard properties can be measured accurately enough to distinguish it from the SM Higgs boson.The question we wish to address in this paper is whether it will be possible in future experiments at the Large Hadron Collider(LHC)to detect a nonstandard Higgs boson and to differentiate it from the SM Higgs.As a model,we consider the most general low-energy effective Lagrangian in terms of the usual SU(2)L×SU(2)R/SU(2)V symmetry breaking pattern which,below the cutoffscaleΛ,has the same spectrum as the SM.The SM is2a particular case and corresponds to the limit whereΛ→∞.This Lagrangian is then used to explore the prospects of the LHC to detect and distinguish a nonstandard from a Standard Higgs boson.In particular,for a variety of Higgs boson masses m H(assuming that m H>2m Z),we determine the values of couplings in the effective Lagrangian for which this is possible by looking at the Higgs boson decay mode H→ZZ→l+l−l+l−, where l is an electron or a muon.It has been shown[5,6]that if a scalar isoscalar resonance is observed,then the measurement of its width offers the best way to distinguish it from the SM Higgs.The deviations from the SM couplings can be used within specific models to estimate the scaleΛof new physics,provided no other nonstandard physics is discovered.As an indication,we have done so for a number of simple Composite Higgs models.This is similar in spirit to an early study by Kosower[10],who also proposed the measurement of the width as a tool to probe the compositeness scale within Composite Higgs models. However,we performed a more detailed statistical analysis and reached somewhat different (less optimistic)conclusions.In the next section we review the theoretical framework and construct the effective Lagrangian of the most general theory with a nonstandard Higgs boson.In Section3we describe the calculation of the signal and ZZ background cross-sections and discuss the issue of whether one can discriminate between a nonstandard Higgs boson and its SM counterpart on the basis of a width measurement.In particular,we derive the statistical significance of a possible discrepancy between the result of such a measurement and the SM expectation.Finally,Section4contains our conclusions.2The Effective LagrangianIn this section,we briefly describe the construction of the most general effective theory with a nonstandard Higgs boson[5,6].The electroweak symmetry breaking sector at low energies contains,besides the Goldstone bosons w a(which become the longitudinal components of W±and Z),one extra scalar particle H(the nonstandard Higgs boson) with the quantum numbers of the SM Higgs boson1.As in the SM,we assume that the Goldstone bosons arise from the spontaneous break-down of a chiral SU(2)L×SU(2)R symmetry down to its diagonal SU(2)V subgroup.As usual,SU(2)L is identified with the gauge group SU(2)W and SU(2)R is the“custodial”symmetry whoseτ3component is identified with hypercharge.The interactions of the Goldstone bosons are described conveniently by using a nonlinear realization[12]of the chiral symmetry,in terms of thefieldΣ=exp i w· τ4 v2+2ξvH+ξ′H2+... Tr ∂µΣ†∂µΣ +L H(3) where L H is the Lagrangian that describes the Higgs boson self-interactionsL H=12H2−λ3v4!H4− (4)andξ,ξ′,λ3andλ4are unknown coefficients.For simplicity,in eqs.(3)and(4)we only show the leading terms,with the ellipsis denoting higher powers in H.The gauge bosons can be introduced by replacing the ordinary derivative in eq.(3)by the covariant one,which,by virtue of the transformation law(2),takes the formDµΣ=∂µΣ+i g2BµΣτ3(5)where g,g′are the usual SU(2)W and U(1)Y gauge couplings respectively.Hence the parametersξ,ξ′etc,represent the couplings of one or more nonstandard Higgs bosons to a pair of weak gauge bosons W aµ.4The fermions are incorporated into the effective Lagrangian as matterfields[12].We shall only consider the quarks of the third family,since these will be the only important ones in our phenomenological investigation.These fermions can be included in thefieldsψL= t L b L ,ψR= t R b R (6)which transform asψL→LψL andψR→RψR under SU(2)L×SU(2)R.Their interactions with the scalars are given byLΣf¯f=h1(v+y1H+...)¯ψLΣψR+h2(v+y2H+...)¯ψLΣτ3ψR+h.c.(7) where h1and h2correspond to Yukawa couplings and can be replaced by the fermion masses,through m t=(h1+h2)v and m b=(h1−h2)v,while y1and y2are new unknown couplings.Again,the ellipsis denotes higher powers in the Higgsfield which are not included in our ing the explicit form(6)in eq.(7),we can read offthe Higgs boson couplings to the top and bottom quarks:L Hf¯f=(h1y1+h2y2)H¯t L t R+(h1y1−h2y2)H¯b L b R+h.c.≡y t(m t/v)H¯t L t R+y b(m b/v)H¯b L b R+h.c.(8) Thus,this Lagrangian introduces two new unknown parameters y t,y b.The SM is a particular case of the effective theory defined above,with the only non-zero couplings being3m2Hξ,ξ′=1,λ3,λ4=(10)16πv2At a scale16πv2s=partial wave unitarity breaks down.Consequently the cutoffΛof the theory,physically associated with the scale at which new degrees of freedom emerge,must lie at or below this scale.From eq.(11)itbecomesclear thatthelargerthe deviation of ξfrom its SM value of 1,the lower the energy scale at which new physics is expected.If Λ≡4πf is the scale of new physics,then by inverting eq.(11),we can write,roughly,ξ2=1+O v 232πv2ξ2 2√4x 2W )+√4x 2Z ) +3m 2t m H m 2H 3/2.(13)where x V =4m 2V /m 2H ,V =W,Z .Here we are assuming that the underlying short-distance dynamics acts so as not to particularly enhance y b over y t .Then,since m t ≫m b ,only the top quark couples significantly to the Higgs boson H ,and we can ignore the coupling to the bottom quark.On the other hand,in the purely scalar sector,tree level amplitudes do not depend on the parameters ξ′,λ3,λ4,etc.The leading one-loop corrections to W L W L scattering and the Higgs boson decay width were computed in Ref.[5,6]and,for phenomenological purposes,they can be incorporated in the effective definition of ξ.We now proceed to investigate the phenomenology of the model presented above.63PhenomenologyIn this section,we explore the phenomenology of a nonstandard Higgs boson at the LHC. We shall only consider Higgs boson masses larger than the ZZ threshold.In this mass range,the Higgs boson decays primarily to gauge boson pairs and thus can be most effectively searched for in the“gold-plated”channelH→ZZ→l+l−l+l−(14)where l is an electron or a muon.This process has been discussed at great length in the literature2,and it is expected that a Standard Higgs boson with mass m H≤500GeV (800GeV)will be discovered at the LHC at an integrated luminosity of10fb−1(100fb−1). The main question we try to answer in the analysis that follows is whether a nonstandard Higgs boson of given mass m H and couplingsξand y t can be detected at the LHC and distinguished from a SM Higgs boson of the same mass.We present results for integrated luminosities of10fb−1and100fb−1,while the center-of-mass energy is assumed to be √4παs(m H).(17)9An irreducible ZZ background also arises from gluon fusion through a quark loop(the ‘box’diagram)gg→ZZ.(18)In fact,this process interferes with the resonant Higgs boson exchange processgg→H→ZZ(19)where the Higgs boson is produced through a top quark loop.An exact calculation for the SM[20]has shown that the effect of the interference is rather small,for most of the range of masses we consider.Towards the upper end of this range,however,(that is m H≈800GeV)the increase in the cross-section caused by the interference term may become sizeable(it is constructive interference).We ignored this effect,and thus ourestimates of the signal rate are somewhat conservative for large masses.We did take into account,however,the contribution of the‘box’diagram to the background,which amounts to approximately50%of the Born process(15),by scaling the cross-section of the latter by1.5.There are also reducible four-lepton backgrounds,primarily from t¯t production.It has been argued[15,21]that,with appropriate isolation cuts and the expected Z mass resolution capability at the LHC,these backgrounds can be reduced to well below the irreducible background levels.We shall therefore ignore them in this study.However,we have taken into account a10%loss of signal rate due to these cuts[21].The main mechanism for Z-boson pair production through a Higgs boson is the process (19).The rate for this process depends on the top quark mass,which is chosen here to be m t=170GeV[22],and also on the nonstandard Yukawa coupling y t.In the Standard Model,for such a top-quark mass,the gluon fusion is the dominant production mechanism for all Higgs boson masses up to1TeV.Leading QCD corrections to this process have been included by multiplying the cross section by another“K-factor”[23,24,25]K=1+ 11π.(20)A second production mechanism for Z pairs through a Higgs boson is gauge boson fusionqq→qqH→qqZZ.(21) We computed the cross-section for this process by using the effective-W approximation [26,27].The scattering amplitudes are calculated at tree-level in the gauge theory from the Lagrangian of Section2.The cross-section is obtained by folding the amplitudes with8the luminosities of the W’s and Z’s inside a quark.Both transverse and longitudinal polarizations are included using the distribution functions of Ref.[28](see also[29]). (The subleading terms in the expressions for these functions depend on the characteristic energy scale of the process under consideration,taken here to be Q2=m2ZZ/4.)The contribution from W L W L(Z L Z L)fusion,which is the least affected by the choice of Q2, is dominant for energies around the peak,since this amplitude is most sensitive to the existence of the Higgs resonance,while the W L W T+W T W T fusion prevails outside this region.The contribution to the cross-section from the interaction of the gauge bosons that does not involve the exchange of the Higgs resonance should in fact be considered as a background[30].We have calculated this background in the effective theory with ξ=0,and subtracted it from the cross-section of the process(21)in our estimates for the signal.We should also remark that in the calculation of both processes(21)and(19),the s-channel Higgs boson exchange diagram is unitarized by including the“running”Higgs boson decay width3in the propagator.This prescription(which can be justified only in the resonance region)differs from other ones,such as including a constant width,by effects which are formally of higher order inλ≡m2H/2v2.However,for W W scattering, it was shown[31]that it is better to use an energy dependent width,because partial wave amplitudes stay closer to the unitarity circle.In terms of event rates,we found that,for gluon fusion,the two prescriptions differ by at most10%for a heavy and wide resonance (see also Ref.[32]).In Tables1–6we present our results for the event rates and the statistical significance of Higgs boson signals for various values ofξand y t.The resonance will have an effective widthΓeff determined by the physical Higgs boson width and by the mass resolution of the detector:Γeff=3The running width is obtained through the relation ImΠH(s)=−√resonance peak occurs,in general,at a lower energy than the nominal Higgs boson mass m H,due to the interference with the non-resonant terms,the energy dependence of the (running)width and the effect of the falling distribution functions.For example,if m H= 800(600)GeV andξ=y t=1,the maximum of the signal cross-section occurs at approximately730(585)GeV.In our results,the Higgs boson mass quoted refers to m H rather than the resonance mass.The results presented for the event rates at the high luminosity(100fb−1)were obtained from those at low luminosity(10fb−1)by scaling by a factor of10.This is not,strictly speaking,a correct procedure,because of the problems a higher luminosity environment may pose(such as deterioration in the energy resolution)[16,33].A full detector simulation is needed in order to assess the magnitude of these effects.Consequently,our results for a luminosity of100fb−1should be regarded as rather optimistic.From these tables it can be seen that a nonstandard Higgs resonance may be distin-guished in principle from the SM Higgs boson by a comparison of its width and total cross-section to the Standard Model predictions.Before we decide whether this can be achieved in practice,we need to know the expected accuracy of a width measurement,as well as the theoretical uncertainties in the calculation of the width and the cross-section. There are few theoretical uncertainties in the calculation of the SM Higgs boson width. Higher order corrections to both gauge boson and fermion decay modes have been com-puted[34,35]and have been found to increase the full width by approximately15%.We chose here not to include this correction,but this does not alter our conclusions.(It will simply change the effective SM value ofξand y t to a value slightly different from1.)For the purposes of deciding whether an observed resonance is consistent with the Standard Model predictions,what matters is to know the latter precisely enough,which we do. Similarly,we have chosen not to include radiative corrections to the width of a nonstan-dard Higgs boson since these can be incorporated into the definition forξand y t[6].In contrast,the accuracy of the cross-section calculation is compromised by the imprecise knowledge of structure functions(amounting to perhaps30%for Higgs boson production [16]),our various approximations(such as the effective-W scheme or the neglect of the interference effects of the‘box’diagram in ZZ production)as well as further corrections beyond the included QCD effects.Consequently,if a Higgs-like resonance is discovered, a comparison of its width to the Standard Model prediction offers the best way to probe its nature.The systematic uncertainty in the measurement of the width arising from smear-10ing may be corrected for by using eq.(22).This will be an accurate procedure only if ΓH>∼∆m H.The statistical error involved in the measurement of the width warrants a more detailed discussion:Suppose that a Higgs resonance is observed at a mass m H and its width measured and found to differ from the expected Standard Model valueΓSM.We wish to attach a statistical significance to this deviation.This statistical significance can be derived from the probability density function according to which the possible measure-ments of the Standard Higgs boson width are distributed.(Any measured quantity is a statistical variable and,as such,obeys some probability distribution function.)To obtain the probability distribution we performed a large number of numerical experiments sim-ulating the possible outcomes of an actual experiment.The procedure adopted was the following:the ZZ invariant-mass range of interest was divided in4-GeV bins.In each of them the total number of events was generated according to a Poisson distribution with mean N S+N B,where N S,N B are the SM signal and background events respectively, expected in that bin.Assuming that the continuum background is known(e.g.from independent experiments)we subtracted the expected background N B in each bin.The resulting distribution represents the signal with an additional noise due to background fluctuations.The mass and the width were obtained byfitting this data with a function of the formm4(E2−m2)2+m2Γ2(23) where E is the invariant mass of the Z pair and m,Γare the parameters of thefit.The exponential encodes the effect of the falling parton distribution functions,while in the expression for the cross-section,factors other than the propagator have a rough m4/E dependence.The value of the constant E0wasfixed from the exact(lowest-order)cross-section for the processpp(gg)→H→ZZ(24) The bestfit occurs for E0=283.8GeV.Repeating this experiment a large number of times,we were able to obtain the proba-bility density,the mean<Γeff>and the standard deviationδΓeff.As mentioned earlier, the physical Higgs boson width can be recovered from the measured,or“effective”,width Γeff through eq.(22).In particular,the spreadδΓSM that corresponds to one standarddeviationδΓeff is given byδΓSM=δΓeff11−(∆m H/Γeff)2(25)Thus,if a resonance of(physical)widthΓH=ΓSM is observed,the statistical significance S associated with this discrepancy is given by the number of standard deviations thatΓH lies away fromΓSM:S=|ΓH−ΓSM|Γeff =cN(27)In the limit of large N and negligible background,c is a constant4.In general,though,c is a function of both the signal N and the background B(and,as can be expected,increases with increasing B or decreasing N).For poor statistics and wide objects(for instance in the case m H=800GeV),the width can hardly be measured,even if a statistically significant signal can be obtained.In Tables7–8we display,for various masses and three representative values of y t, namely y2t=0.5,1and2,the range of values ofξfor which the nonstandard Higgs boson is observable and distinguishable from the SM Higgs.Results are presented for integrated luminosities of10fb−1and100fb−1.The criteria used in compiling these tables are the following:For a signal to be declared“observable”we require that it consists of at least10 events and that its statistical significance is greater than5σ.For it to be distinguishable from the SM Higgs boson,we require that its widthΓH differ from the Standard Model value by at least three standard deviations as defined by eq.(25).If this criterion is not satisfied,one could in principle examine the signal event rate.However,given the large uncertainty in the theoretical calculation,we opted not to use this information.4ConclusionsOur conclusions are consistent with the expectation that a SM Higgs boson will be de-tected at the LHC in this channel provided its mass is less than about500GeV(at 10fb−1)or800GeV(at100fb−1).As y t becomes smaller or larger than unity,this mass range will shrink or expand.For example,at y2t=0.5andξ=1the respective mass ranges at the low and high luminosity options considered are330GeV<∼m H<∼430GeV and2M Z<∼m H<∼680GeV respectively.We observe further that at10fb−1,only modelswith relatively largeξcan be differentiated from the Standard Model.This is primarily due to the low statistics and the consequent imprecision in the width measurement.It might be possible,however,to improve the statistics by a less strict set of cuts on the final state leptons(or Z’s).The situation is considerably better at100fb−1,as can be seen from Table8.In certain cases whereξis small,the nonstandard Higgs boson is too narrow to be resolved,even though a SM Higgs of the same mass is not.In this case one could tell that the Higgs boson is nonstandard by comparing the detector resolution to the expected SM width,but it is not possible to determine a value forξ.As we emphasized earlier,the deviation of the values of the parametersξand y t from unity is a measure of the cutoffΛ,which can be thought of as an upper bound to the scale of new physics.Precise relations,however,are model-dependent.In the context of specific models,the results presented in Tables7-8reveal the energy scale that the LHC will be able to probe.For example,if m H=500GeV,where the sensitivity of the LHC to the measurement ofξis about30%(see Table8),the scale probed isΛ=4.3TeV in the SU(3)L×SU(3)R/SU(3)V model of Ref.[8]whereξ2=1−v2/f2,Λ=2.2TeV in the SU(5)/SO(5)model[9]whereξ2=1−(v2/4f2),andfinallyΛ=16TeV in the SU(4)/SU(2)×SU(2)model[10]in whichξ2=1−(4v2/f2).In the above,Λ=4πf is the compositeness scale of the underlying new strong dynamics and v=246GeV,while we have assumed y t=1in all of these cases.In a general Two-Higgs-Doublet model where a gap exists between the mass m H of the lightest neutral state and that of the heavier (nearly degenerate)scalars(M,say),the parameterξgenerally approaches its SM value faster:ξ2=1−O(m4H/M4);our results indicate that,in this case,it will be very hard to determine the existence of a non-minimal scalar sector solely from a measurement of the width of the observed resonance(see also Ref.[36]).AcknowledgementsWe thank R.S.Chivukula,M.Golden,ne and B.Zhou for useful conversations. This work was supported in part under NSF contract PHY-9057173and DOE contract DE-FG02-91ER40676.m H=350GeVξWidth Width Width39(5.6)26(7.6) 3.70.500.36 4.0224.242(6.0)34(9.0)14(5.2)1.00 1.4115.363.349(6.9)43(9.3)18(5.0)1.50 3.1834.012859(8.2)45(8.2)22(4.4)2.00 5.6560.3219Table1:Event rates and decay widths for various Higgs boson masses m H andξat the LHC at a luminosity of10fb−1for standard top Yukawa coupling and m t=170GeV. The statistical significance is also shown for signals consisting of more than10events.m H=400GeV m H=800GeV Ev.(Sg.)Ev.(Sg.)Ev.(Sg.)Ev.(Sg.)0.250.09 4.8525.148.6403(18.5)205(22.9)50(9.3)14(4.0)0.750.8017.072.4167446(20.2)340(28.1)82(10.1)28(4.0)1.252.2141.2167403535(23.7)368(24.6)111(8.6)44(2.8)1.75 4.3277.63092.00 5.65100398m H=350GeVξWidth Width Width20(3.0)15(4.9) 3.10.500.36 3.8918.622(3.3)18(5.4)8.81.00 1.4115.157.628(4.2)25(6.0)11(3.4)1.50 3.1833.912339(5.7)28(5.6)14(3.1)2.00 5.6560.1214SM 1.4115.363.3Table3:Event rates and decay widths for various masses andξat the LHC at a luminosity of10fb−1for nonstandard top Yukawa coupling y2t=0.5and m t=170GeV.The statistical significance is also shown for signals consisting of more than10events.m H=400GeV m H=800GeV Ev.(Sg.)Ev.(Sg.)Ev.(Sg.)Ev.(Sg.)0.250.09 3.1815.531.7204(9.9)126(15.5)35(7.4)10(3.0)0.750.8015.362.8150245(11.7)190(18.3)50(7.0)18(2.9)1.252.2139.5158386334(15.6)220(16.6)74(6.5)32(2.2)1.75 4.3275.92992.00 5.6598.6388446(20.2)340(28.1)82(10.1)28(4.0)m H=350GeVξWidth Width Width75(9.9)42(11.1) 4.90.500.36 4.2935.582(10.7)64(14.5)21(6.8)1.00 1.4115.574.589(11.5)78(14.8)29(7.2)1.50 3.1834.314099(12.6)77(12.7)35(6.5)2.00 5.6560.5231SM 1.4115.363.3Table5:Event rates and decay widths for various masses andξat the LHC at a luminosity of10fb−1for nonstandard Higgs-top Yukawa coupling y2t=2and m t=170GeV.The statistical significance is also shown for signals consisting of more than10events.m H=400GeV m H=800GeV Ev.(Sg.)Ev.(Sg.)Ev.(Sg.)Ev.(Sg.)0.250.098.1944.282.4795(33.3)301(28.9)65(10.4)20(4.8)0.750.8020.391.5201846(35.0)546(40.3)131(14.0)44(5.7)1.252.2144.5186437936(38.1)636(37.4)178(12.7)67(3.9)1.75 4.3280.13282.00 5.65104417446(20.2)340(28.1)82(10.1)28(4.0)m H(GeV)y2t=1300–350ξ>∼1.70400ξ>∼1.60450ξ>∼1.70500–Range ofξy2t=0.5y2t=2––ξ>∼1.40ξ>∼1.400.20<∼ξ<∼0.45ξ>∼1.15ξ>∼1.205000.20<∼ξ<∼0.60ξ>∼1.35ξ>∼1.20ξ>∼1.45ξ>∼1.35–ξ>∼1.55––Table8:Range of values of the parameterξfor which the nonstandard Higgs boson resonance is both observable and distinguishable from the Standard Higgs at100fb−1of luminosity and three values of the nonstandard Yukawa coupling y t.The range0<ξ≤2.0 has been explored.References[1]ALEPH Collaboration,D.Decamp et al.,Phys.Rev.216(1992)253;DELPHI Collaboration,P.Abreu et al.,Nucl.Phys.B373(1992)3;L3Collaboration,O.Adriani et al.,Phys.Lett.B303(1993)391;OPAL Collaboration,M.Akrawy et al.,Phys.Lett.B253(1991)511.[2]R.Dashen and H.Neuberger,Phys.Rev.Lett.50(1983)1897.[3]B.W.Lee,C.Quigg and H.Thacker,Phys.Rev.D16(1977)1519.[4]G.’t Hooft,in:Recent Developments in Gauge Theories,edited by G.’t Hooft(Plenum Press,New York,1980).[5]R.S.Chivukula and V.Koulovassilopoulos,Phys.Lett.B309(1993)371.[6]V.Koulovassilopoulos and R.S.Chivukula,Phys.Rev.D50(1994)3218.[7]D.B.Kaplan and H.Georgi,Phys.Lett.B136(1984)183;D.B.Kaplan,S.Dimopoulos and H.Georgi,Phys.Lett.B136(1984)187.[8]T.Banks,Nucl.Phys.B243(1984)125.[9]H.Georgi and D.B.Kaplan,Phys.Lett.B145(1984)216;M.J.Dugan,H.Georgi and D.B.Kaplan,Nucl.Phys.B254(1985)299.[10]D.A.Kosower,in Physics of the Superconducting Supercollider,Proceedings of the1986Summer Study on the Physics of the SSC,Snowmass1986,edited by R.Don-aldson and J.Marx.[11]Y.Nambu,Enrico Fermi Institute Preprint EFI88-39;V.A.Miransky,M.Tanabashi,and K.Yamawaki,Phys.Lett.B221(1989)177;Mod.Phys.Lett.A4(1989)1043;W.A.Bardeen,C.T.Hill,and M.Lindner,Phys.Rev.D41(1990)1647.[12]S.Coleman,J.Wess and B.Zumino,Phys.Rev.177(1969)2239;C.G.Callan,S.Coleman,J.Wess and B.Zumino,Phys.Rev.177(1969)2247.[13]R.S.Chivukula,M.Dugan and M.Golden,Phys.Lett.B336(1994)62.。

a r X i v:071.3109v 1 [h e p -p h ] 16 O c t 2007Heavy MSSM Higgs Bosons at CMS:“LHC wedge”and Higgs-Mass PrecisionS.Heinemeyer 1a ,A.Nikitenko 2,and G.Weiglein 3b1Instituto de Fisica de Cantabria (CSIC-UC),Santander,Spain2Imperial College,London,UK;on leave from ITEP,Moscow,Russia 3IPPP,University of Durham,Durham DH13LE,UKAbstract.The search for MSSM Higgs bosons will be an important goal at the LHC.In order to analyze the search reach of the CMS experiment for the heavy neutral MSSM Higgs bosons,we combine the latest results for the CMS experimental sensitivities based on full simulation studies with state-of-the-art theoretical predictions of MSSM Higgs-boson properties.The experimental analyses are done assuming an integrated luminosity of 30or 60fb −1.The results are interpreted as 5σdiscovery contours in MSSM M A –tan βbenchmark scenarios.Special emphasis is put on the variation of the Higgs mixing parameter µ.While the variation of µcan shift the prospective dis-covery reach (and correspondingly the “LHC wedge”region)by about ∆tan β=10,the discovery reach is rather stable with respect to the impact of other supersymmetric parameters.Within the discovery region we analyze the accuracy with which the masses of the heavy neutral Higgs bosons can be determined.An accuracy of 1–4%should be achievable,depending on M A and tan β.PACS.14.80.Cp Non-standard-model Higgs bosons –12.60.Jv Supersymmetric models1IntroductionIdentifying the mechanism of electroweak symmetry breaking will be one of the main goals of the LHC.The most popular models are the Higgs mechanism within the Standard Model (SM)and within the Minimal Su-persymmetric Standard Model (MSSM)[1].Contrary to the case of the SM,in the MSSM two Higgs doublets are required.This results in five physical Higgs bosons instead of the single Higgs boson of the SM.These are the light and heavy CP -even Higgs bosons,h and H ,the CP -odd Higgs boson,A ,and the charged Higgs bo-son,H ±.The Higgs sector of the MSSM can be spec-ified at lowest order in terms of the gauge couplings,the ratio of the two Higgs vacuum expectation val-ues,tan β≡v 2/v 1,and the mass of the CP -odd Higgs boson,M A .Consequently,the masses of the CP -even neutral Higgs bosons and the charged Higgs boson are dependent quantities that can be predicted in terms of the Higgs-sector parameters.Higgs-phenomenology in the MSSM is strongly affected by higher-order correc-tions,in particular from the sector of the third gener-ation quarks and squarks,so that the dependencies on various other MSSM parameters can be important.The current exclusion bounds within the MSSM [2,3,4]and the prospective sensitivities at the LHC are usually displayed in terms of the parameters M A and tan βthat characterize the MSSM Higgs sector at low-1In our analysis we do not consider diffractive Higgs production,pp →p ⊕H ⊕p [11].For a detailed discussion of the search reach for the heavy neutral MSSM Higgs bosons in diffractive Higgs production we refer to Ref.[12].Colliders-Higgs Phenomenology Contributed Talk500N S63172.4×10−3R Mφ0.1760.1872.8300N S72.932.86.4×10−3R Mφ0.2160.2303.2500572.0×10−20.2002.6Table 3.Required number of signal events,N S,with L=30fb−1for a5σdiscovery in the channelφ→τ+τ−→µ+jet.The other quantities are defined as in Tab.1.The results quoted in Tabs.1–3for the required number of signal events depend only on the Higgs-boson mass,i.e.the event kinematics,but are indepen-dent of any specific MSSM scenario.In order to deter-mine the5σdiscovery contours in the M A–tanβplane these results have to be confronted with the MSSM predictions.The number of signal events,N ev,for a given parameter point is evaluated viaN ev=L×σb¯bφ×BR(φ→τ+τ−)×BRττ×εexp.(4)Here L denotes the luminosity collected with the CMS detector,σb¯bφis the Higgs-boson production cross sec-tion,BR(φ→τ+τ−)is the branching ratio of the Higgs boson toτleptons,BRττis the product of the branching ratios of the twoτleptons into their respec-tivefinal state,BR(τ→jet+X)≈0.65,(5) BR(τ→µ+X)≈BR(τ→e+X)≈0.175,(6)andεexp denotes the total experimental selection effi-ciency for the respective process(as given in Tabs.1–3).For our numerical predictions of total cross sections (see Ref.[18]and references therein)and branching ra-tions of the MSSM Higgs bosons we use the program FeynHiggs[19,20,21,22].We take into account effects from higher-order corrections and from decays of the heavy Higgs bosons into supersymmetric particles.In spite of the escaping neutrinos,the Higgs-boson mass can be reconstructed in the H,A→ττchannel from the visibleτmomenta(τjets)and the missing transverse energy,E missT,using the collinearity approx-imation for neutrinos from highly boostedτ’s.In the investigated region of M A and tanβthe two states A and H are nearly mass-degenerate.For most values of the other MSSM parameters the mass difference of A and H is much smaller than the achievable mass resolution,and the difference in reconstructing the A or the H will have no relevant effect on the achiev-able accuracy in the mass determination.The preci-sion∆Mφ/Mφshown in Tabs.1–3is derived for the border of the parameter space in which a5σdiscov-ery can be claimed,i.e.with N S observed Higgs events. The statistical accuracy of the mass measurement has been evaluated via∆Mφ/Mφ=R Mφ/S.Heinemeyer,A.Nikitenko,G.Weiglein Heavy MSSM Higgs Bosons at CMS...2A corresponding analysis in benchmark scenariosfulfilling cold dark matter constraints can be found in Ref.[23].3Since the results of the experimental simulation for this channel are available only for two M A values,the interpo-lation is a straight line.This may result in a slightly larger uncertainty of the results compared to the other two chan-nels.Fig.1.Variation of the5σdiscovery contours obtained in the m maxhscenario for different values ofµfrom the channels b¯bφ,φ→τ+τ−→jets(top),→e+jet(middle),→µ+jet(bottom).4Numerical results for the Higgs-boson mass precisionThe expected statistical precision of the heavy Higgs-boson masses is evaluated according to eq.(7).In Fig.2 we show the expected precision for the mass measure-ment achievable from the channel b¯bφ,φ→τ+τ−using thefinal stateτ+τ−→jets.Within the5σdiscovery region we have indicated contour lines corresponding to different values of the expected precision,∆M/M.Colliders-Higgs Phenomenology Contributed Talk。

a r X i v :0709.4408v 1 [h e p -p h ] 27 S e p 2007SUSY HIGGS BOSONS AT THE LHC G.WEIGLEIN IPPP,Department of Physics,University of Durham,South Road,Durham DH13LE,UK Recent results on MSSM Higgs physics at the LHC are reviewed.The dependence of the LHC discovery reach in theb ¯bH/A,H/A →τ+τ−channel on the underlying SUSY scenario is analysed.This is done by combining the latest results for the prospective CMS experimen-tal sensitivities for an integrated luminosity of 30or 60fb −1with state-of-the-art theoretical predictions of MSSM Higgs-boson properties.The results are interpreted in terms of the parameters governing the MSSM Higgs sector at lowest order,M A and tan β.While the higgsino mass parameter µhas a significant impact on the prospective discovery reach (and correspondingly the “LHC wedge”region),it is found that the discovery reach is rather stable with respect to variations of other supersymmetric parameters.Within the discovery region a determination of the masses of the heavy neutral Higgs bosons with an accuracy of 1–4%seems feasible.It is furthermore shown that Higgs-boson production in central exclusive diffractive channels can provide important information on the properties of the neutral MSSM Higgs bosons.1Introduction Signatures of an extended Higgs sector would provide unique evidence for physics beyond the Standard Model (SM).While models with an extended Higgs sector often give rise to a relatively light SM-like Higgs boson over a large part of their parameter space,detecting heavy states of anextended Higgs sector and studying their properties will be of utmost importance for revealing the underlying physics.2Dependence of the LHC discovery reach on the SUSY scenarioIn Ref.1the reach of the CMS experiment with 30or 60fb −1for the heavy neutral MSSM Higgs bosons has been analysed focusing on the channel b ¯bH/A,H/A →τ+τ−with the τ’s subsequently decaying to jets and/or leptons.The experimental analysis,yielding the number of events needed for a 5σdiscovery (depending on the mass of the Higgs boson)was performed with full CMS detector simulation and reconstruction for the final states of di-τ-lepton decays 2.The events for the signal and background processes were generated using PYTHIA 3.The experimental analysis has been combined with predictions for the Higgs-boson masses,produc-tion processes and decay channels obtained with the code FeynHiggs 4,taking into account all relevant higher-order corrections as well as possible decays of the heavy Higgs bosons into su-persymmetric particles.The results have been interpreted in terms of the two parameters tan β,the ratio of the vacuum expectation values of the two Higgs doublets of the MSSM,and M A ,the mass of the CP-odd Higgs boson.The variation of the discovery contours in the M A–tanβplane indicates the dependence of the“LHC wedge”region,i.e.the region in which only the light CP-even MSSM Higgs bosoncan be detected at the LHC at the5σlevel,on the details of the supersymmetric theory.See Ref.5for previous analyses.Figure1:Variation of the5σdiscovery contours obtained from the channel b¯bφ,φ→τ+τ−→jets in the m maxh benchmark scenario for different values ofµ(left plot).The right plot shows the result in the case where no decays of the heavy Higgs bosons into supersymmetric particles are taken into account.Fig.1shows the variation of the5σdiscovery contours obtained from the channel b¯bφ,φ→τ+τ−→jets in the m maxhbenchmark scenario6for various values of the higgsino mass parameter µ.The parameterµenters via higher-order corrections affecting in particular the bottom Yukawa coupling as well as via its kinematic effect in Higgs decays into charginos and neutralinos.Both effects can be seen in Fig.1.While the left plot shows the full result,in the right plot no decays of the Higgs bosons into supersymmetric particles are taken into account,so that the right plot purely displays the effect of higher-order parison of the two plots shows that in the region of large tanβ(corresponding to larger values of M A on the discovery contours)the dominant effect arises from higher-order corrections.For lower values of tanβ,on the other hand, the modification of the Higgs branching ratio as a consequence of decays into supersymmetric particles yields the dominant effect on the5σdiscovery contours.The largest shift in the5σdiscovery contours amounts up to about∆tanβ=10.The discovery contours have been shown to be rather stable with respect to the impact of other supersymmetric contributions1.Figure2:The statistical precision of the Higgs-boson mass measurement achievable from the channel b¯bφ,φ→τ+τ−→jets in the m maxhbenchmark scenario forµ=−200GeV(left)andµ=+200GeV(right)is showntogether with the5σdiscovery contour.The prospective accuracy of the mass measurement of the heavy neutral MSSM Higgs bosonsin the channel b¯bH/A,H/A→τ+τ−is analysed in Fig.2.The statistical accuracy of the mass measurement has been evaluated via∆Mφ√the M A–tanβplane of the MSSM(using the m maxbenchmark scenario6)for different luminos-hity scenarios.It is found that the CED Higgs-boson production channel can cover an interesting part of the MSSM parameter space at the5σlevel if the CED channel can be utilised at high in-stantaneous luminosity(which requires in particular to bring pile-up background under control). For an effective luminosity of600fb−1×2(see Ref.8)the discovery of a heavy CP-even Higgs boson with a mass of about140GeV will be possible for all values of tanβ.This is of particular interest in view of the“wedge region”left uncovered by the conventional search channels for heavy MSSM Higgs bosons(see above).In the high-tanβregion the discovery reach extends beyond M H=200GeV at the5-σlevel.If the Higgs bosons h and/or H have been detected in the conventional search channels,a lower statistical significance may be sufficient for the CED production of h and H,corresponding to a larger coverage in the M A–tanβplane.The CED Higgs-boson production channel will provide in this case important information on the Higgs-boson properties and may even allow a direct measurement of the Higgs-boson width8.AcknowledgmentsThe author gratefully acknowledges the collaboration with S.Gennai,S.Heinemeyer,A.Kali-nowski,V.A.Khoze,R.Kinnunen,S.Lehti,A.Nikitenko,M.G.Ryskin,W.J.Stirling and M.Tasevsky on the results presented in this paper.He also thanks the organisers of the42nd Rencontres de Moriond for the kind invitation and the pleasant atmosphere at the meeting.References1.S.Gennai,S.Heinemeyer,A.Kalinowski,R.Kinnunen,S.Lehti,A.Nikitenko andG.Weiglein,arXiv:0704.0619[hep-ph],to appear in Eur.Phys.J.C.2.CMS Physics Technical Design Report,Volume2.CERN/LHCC2006-021,see:cmsdoc.cern.ch/cms/cpt/tdr/.3.T.Sjostrand et al.,mun.135(2001)238.4.S.Heinemeyer,W.Hollik,G.Weiglein,mun.124(2000)76;hep-ph/0002213;Eur.Phys.J.C9(1999)343;G.Degrassi,S.Heinemeyer,W.Hollik, P.Slavich,G.Weiglein,Eur.Phys.J.C28(2003)133;M.Frank,T.Hahn,S.Heine-meyer,W.Hollik,H.Rzehak,G.Weiglein,JHEP02(2007)047;see:www.feynhiggs.de.5.ATLAS Collaboration,Detector and Physics Performance Technical Design Report,CERN/LHCC/99-15(1999);R.Kinnunen and A.Nikitenko,CMS note2003/006;J.Thomas,ATL-PHYS-2003-003;D.Cavalli and D.Negri,ATL-PHYS-2003-009;S.Ab-dullin et al.,Eur.Phys.J.C39S2(2005)41;M.Carena,S.Heinemeyer,C.Wagner andG.Weiglein,Eur.Phys.J.C45(2006)797.6.M.Carena,S.Heinemeyer,C.Wagner and G.Weiglein,Eur.Phys.J.C26(2003)601.7.V.A.Khoze,A.D.Martin and M.Ryskin,hep-ph/0006005;Eur.Phys.J.C19(2001)477[Erratum-ibid.C20(2001)599].8.S.Heinemeyer,V.A.Khoze,M.G.Ryskin,W.J.Stirling,M.Tasevsky and G.Weiglein,arXiv:0708.3052[hep-ph].9.A.Kaidalov,V.A.Khoze,A.D.Martin,M.Ryskin,Eur.Phys.J.C33(2004)261;M.Boonekamp,J.Cammin,vignac,R.Peschanski,C.Royon,Phys.Rev.D73 (2006)115011;J.Ellis,J.Lee,A.Pilaftsis,Phys.Rev.D70(2004)075010;Phys.Rev.D71(2005)075007;V.A.Khoze,A.D.Martin,M.Ryskin,Eur.Phys.J.C34(2004) 327;B.Cox,F.Loebinger and A.Pilkington,arXiv:0709.3035[hep-ph].。

Adsorption of heavy metal ion from aqueous single metal solutionby chemically modified sugarcane bagasseOsvaldo Karnitz Jr.a ,Leandro Vinicius Alves Gurgel a ,Ju´lio Ce ´sar Perin de Melo a ,Vagner Roberto Botaro a ,Taˆnia Ma ´rcia Sacramento Melo a ,Rossimiriam Pereira de Freitas Gil b ,Laurent Fre´de ´ric Gil a,*aDepartamento de Quı´mica,Instituto de Cie ˆncias Exatas e Biolo ´gicas,Universidade Federal de Ouro Preto,35400-000Ouro Preto,Minas Gerais,BrazilbDepartamento de Quı´mica,Instituto de Cie ˆncias Exatas,Universidade Federal de Minas Gerais,31270-901Belo Horizonte,Minas Gerais,BrazilReceived 22November 2005;received in revised form 28April 2006;accepted 2May 2006Available online 14July 2006AbstractThis work describes the preparation of new chelating materials derived from sugarcane bagasse for adsorption of heavy metal ions in aqueous solution.The first part of this report deals with the chemical modification of sugarcane bagasse with succinic anhydride.The carboxylic acid functions introduced into the material were used to anchor polyamines,which resulted in two yet unpublished modified sugarcane bagasse materials.The obtained materials were characterized by elemental analysis and infrared spectroscopy (IR).The sec-ond part of this reports features the comparative evaluation of the adsorption capacity of the modified sugarcane bagasse materials for Cu 2+,Cd 2+,and Pb 2+ions in aqueous single metal solution by classical titration.Adsorption isotherms were studied by the Freundlich and Langmuir models.Ó2006Elsevier Ltd.All rights reserved.Keywords:Adsorption;Modified sugarcane bagasse;Polyamines;Isotherm;Heavy metals1.IntroductionWater pollution is a major environmental problem faced by modern society (Baird,1995)that leads to eco-logical disequilibrium and health hazards (Kelter et al.,1997).Heavy metal ions such as copper,cadmium,lead,nickel,and chromium,often found in industrial waste-water,present acute toxicity to aquatic and terrestrial life,including humans.Thus,the discharge of effluents into the environment is a chief concern.The methods commonly used to remove toxic heavy metal from municipal and industrial wastewater are based on the adsorption of ions onto insoluble compounds and the separation of the sed-iments formed.Many efforts have been made recently tofind cheaper pollution control methods and materials(Panday et al.,1985;Ali and Bishtawi,1997;Acemiog˘lu and Alma,2001).The new material world trends point to the importance of using industrial and agricultural residues as production starting materials.Reusing and recycling these residues can minimize the environmental problems associated with their build-up and reduce the use of noble starting materi-als.This trend has contributed to the reconsideration of the use of traditional biomaterials such as natural lignocellu-losic fibers to substitute synthetic polymers,for example,since in many cases they have a better performance.Brazil is the world leading producer of sugarcane for both the alcohol and the sugar industries.These industries produce a large amount of sugarcane bagasse and although it is burned to produce energy for sugar mills,leftovers are still significant.Thus,on account of the importance of0960-8524/$-see front matter Ó2006Elsevier Ltd.All rights reserved.doi:10.1016/j.biortech.2006.05.013*Corresponding author.Tel.:+553135591717;fax:+55315511707.E-mail address:laurent@iceb.ufop.br (L.F.Gil).Bioresource Technology 98(2007)1291–1297bagasse sugar as an industrial waste,there is a great interest in developing chemical methods for recycling it.Sugarcane bagasse has around50%cellulose,27%polyoses,and23% lignin(Caraschi et al.,1996).These three biological poly-mers have many hydroxyl and/or phenolic functions that can be chemically reacted to produce materials with new properties(Xiao et al.,2001;Navarro et al.,1996).Despite the many studies of the chemical modification of cellulose published around the world in this area(Gurnani et al.,2003;Gellerested and Gatenholm,1999),only a few have investigated the modification of bagasse sugar(Krish-nan and Anirudhan,2002;Orlando et al.,2002).This work describes the preparation and the evaluation of new chelating materials from sugarcane bagasse to adsorb heavy metal ions in aqueous solution.In a prelimin-ary study,it has been chosen to study the adsorption of Cu2+,Cd2+,and Pb2+.Thefirst part of this work describes the modification of sugarcane bagasse with succinic an-hydride to introduce carboxylic functions to sugarcane bagasse and the chemical introduction of commercial linear polyamine via the formation of amide functions.It is well known that polyamines have powerful chelating properties, mainly towards ions such as Cu2+,Zn2+,and Pb2+(Bian-chi et al.,1991;Martell and Hancock,1996).The second part of this work evaluates the adsorption of Cu2+,Cd2+,and Pb2+onto three modified sugarcane bag-asses(MSBs)from aqueous single metal ion solutions by classical titration.The results were analyzed by the Lang-muir and Freundlich models(Ho et al.,2005).2.Methods2.1.MaterialsPolyamines ethylenediamine3and triethylenetetramine 4were used in this work.Succinic anhydride,1,3-diiso-propylcarbodiimide(DIC),and triethylenetetramine,from Aldrich,were used without purification.Ethylenediamine and dimethylformamide were distilled before use.Pyridine was refluxed with NaOH and distilled.2.2.Sugarcane bagasse preparationSugarcane bagasse was dried at100°C in an oven for approximately24h and nextfiber size was reduced to pow-der by milling with tungsten ring.The resulting material was sieved with a4-sieve system(10,30,45,and60mesh). Then,the material was washed with distilled water under stirring at65°C for1h and dried at100°C.Finally,it was washed anew in a sohxlet system with n-hexane/ ethanol(1:1)as solvent for4h.2.3.Synthesis of MSBs1and2Washed and dried sugarcane bagasse(5.02g)was trea-ted with succinic anhydride(12.56g)under pyridine reflux (120mL)for18h.The solid material wasfiltered,washed in sequence with1M solution of acetic acid in CH2Cl2, 0.1M solution of HCl,ethanol95%,distilled water,and finally with ethanol95%.After drying at100°C in an oven for30min and in a desiccator overnight,MSB1(7.699g) was obtained with a mass gain of53.4%.MSB2was obtained by treatment of1with saturated NaHCO3solu-tion for30min and afterwards byfiltering using sintered filter and washing with distilled water and ethanol.2.4.Synthesis of MSBs5and6The process used to introduce amine functions was the same as that used to prepare MSB5and6.MSB1was trea-ted with5equiv of1,3-diisopropylcarbodiimide(DIC)and 6equiv of polyamine in anhydrous DMF at room tempera-ture for22h under stirring.Afterfiltration,the materials were washed with DMF,a saturated solution of NaHCO3, distilled water,andfinally with ethanol.Next,they were dried at80°C in an oven for30min and in a desiccator overnight.2.5.Kinetic study of metal ion adsorption of MSBs2,5,and6Experiments with each material and metal ion were per-formed to determine the adsorption equilibrium time from 10to90min in10min intervals.The amount of100mg MSB was placed in a250-mL Erlenmeyer with100.0mL metal ion solution with concentration of200mg/L under stirring.The experiments were done at pHs5.8for Cu2+, 7.0for Cd2+,and6.2for Pb2+,optimal values to obtain the best adsorption.To adjust pH values,was added NaOH solution(0.01mol/L)into metal solutions with MSB.Afterfiltration,metal ion concentration was deter-mined by EDTA titration.2.6.pH study of metal ion adsorption of MSBs2,5,and6Experiments with each material and metal ion were per-formed to determine the effect of pH on ion adsorption.An amount of100mg MSB was placed into a250-mL Erlen-meyer with100.0mL of metal ion solution200mg/L under stirring.pH was calibrated with HCl or NaOH solutions (0.1–1.0mol/L).The reaction times used were30min (MSB2)or40min(MSB5and6)for Cu2+and Cd2+, and40min(MSB2)or50min(MSB5and6)for Pb2+. Metal ion concentration was determined afterfiltration by EDTA titration.No significative variation of pH was observed at the end of each experiment.2.7.Adsorption isotherms of MSBs2,5,and6Experiments were performed for each material and metal ion to determine adsorption isotherms.In each experiment,100mg of MSB was placed into a250-mL Erlenmeyer with100.0mL of metal ion solution in specific concentrations(between200mg/L and400mg/L)under stirring.Each experiment was performed at the pH of1292O.Karnitz Jr.et al./Bioresource Technology98(2007)1291–1297larger ion adsorption during the time necessary for equilib-rium (Tables 3and 4).After filtration,the metal ion con-centration was determined by EDTA titration.2.8.Characterization of the new obtained materials MSB 1,2,5,and 6were characterized by IR spectro-scopy in a Nicolet Impact 410equipment with KBr.Elemental analyses were accomplished in Analyzer 2400CHNS/O Perkin Elemer Series II.3.Results and discussion3.1.Synthesis of MSBs 1,2,5,and 6The synthesis route used to prepare MSBs 1,2,5,and 6are presented in Scheme 1.Prewashed sugarcane bagasse was succinylated for various periods of time.The degree of succinylation of the bagasse fibers was determined by measuring the quantity of acid function.The results are shown in Fig.1.The concentration of carboxylic functions per mg of bagasse was determined by retro titration.For this,MSB 1was initially treated with an excess solution of NaOH (0.01mol/L)for 30min.Soon afterwards the material was filtered and the obtained solution was titrated with an HCl solution (0.01mol/L).The highest degree of succinylation was reached after 18-h ing this reaction time,sugarcane bagasse was succinylated to pro-duce MSB 1,which presented a weight gain of 54%and a concentration of carboxylic acid function per mg of 3.83·10À6mol.Next,MSB 1was treated with a saturated NaHCO 3solution to produce MSB 2.Starting from MSB 1,two polyamines were introduced:ethylenediamine 3and triethylenetetramine 4.The method-ology used to introduce the polyamines was the same for the two MSBs 5and 6,as shown in Scheme 1.Concentra-tions of 2.4·10À6mol (5)and 2.6·10À6mol (6)of amine function per mg of material were determined by back titra-tion with excess HCl solution.The introduction of the amine functions was also verified by IR spectroscopy (Table 1)and elemental analysis (Table 2).3.2.Characterization of MSBs 1,5,and 6Characterization of carboxylated MSB 1was accom-plished by IR spectroscopy.The spectrum of unmodified sugarcane bagasse and MSB 1are presented in Fig.2.The spectrum of MSB 1displayed two strong bands at 1740and 1726cm À1in relation to that of unmodified sug-arcane bagasse.This demonstrated the presence of two types of carbonyl functions,one relative to carboxylic acid and another relative to the ester.The acid and ester IR bands indicate that succinic anhydride acylated theO.Karnitz Jr.et al./Bioresource Technology 98(2007)1291–12971293hydroxy group of bagasse to generate an ester bond with consequent release of a carboxylic acid functional group.The spectra of MSBs5and6(Figs.3and4,respectively) showed three new strong bands at1550–1650cmÀ1(see data in Table1)corresponding to the presence of amide and amine functions,and one band at1060cmÀ1 corresponding to C–N stretch.The bands at1635and 1650cmÀ1(Fig.3)correspond to the axial deformation of the carbonyl of the amide function and the angular deformation of the N–H bond of the amine function.The band at1575cmÀ1corresponds to the angular deformation of the N–H bond of the amide function.The band at 1159cmÀ1(Fig.4)corresponds to the asymmetric stretch of C–N–C bond.The main bands observed in all MSBs are presented in Table1.MSB elemental analysis data presented in Table2show a modification in the carbon and hydrogen composition of MSB1and a larger proportion of nitrogen as the number of amine functions in the used polyamine increases.3.3.Study of adsorption of Cu2+,Cd2+and Pb2+on MSBs2,5,and6The study of the MSB adsorption properties was accom-plished for each material and metal ion.A kinetic study and an adsorption study as a function of pH werefirst carried out.3.3.1.Effect of contact timeThe kinetic study of MSB2with Cu2+,Cd2+,and Pb2+ ions in aqueous solution is presented in Fig.5.Adsorption equilibrium was reached after20min for Cd2+ions.A time of30min was chosen for all studies of MSB2with Cd2+. The adsorption equilibrium times chosen for pH and con-centration dependent experiments are presented in Table3.Similar studies were accomplished for MSBs5and6for Cu2+,Cd2+,and Pb2+.The results are presented in Table3.3.3.2.pH EffectThe removal of metal ions from aqueous solutions by adsorption is dependent on solution pH as it affects adsor-Table1Main IR spectrum bands observed in MSBs1,5,and6MSB Main bands observed(cmÀ1)11740,172651745,1650,1635,1575,1423,1060 61738,1651,1635,1560,1400,1159,1060 Table2Elemental analysis of MSBs1,2,5,and6C(%)H(%)N(%) Sugarcane bagasse43.98 6.020.13MSB145.41 5.620.10MSB238.04 5.140.01MSB544.01 6.51 2.21MSB646.88 6.65 3.431294O.Karnitz Jr.et al./Bioresource Technology98(2007)1291–1297bent surface charge,the degree of ionization,and the species of adsorbates.The study of adsorption of Cd 2+,Cd 2+,and Pb 2+on MSB 2as a function of pH was accom-plished with the reaction times given in Table 3;the results are presented in Fig.6.The adsorption of the three metal ions increases with the increase in pH.Maximum removal of Cd 2+was observed above pH 6and in the case of Pb 2+and Cu 2,above pH 5and 5.5.Similar studies were accomplished for MSBs 5and 6and Cu 2+,Cd 2+and Pb 2+with similar results,as shown in Table 4.3.3.3.Adsorption isothermsThe Langmuir (Ho et al.,2005)(Eq.(1))and Freundlich (Eq.(2))isotherms were evaluated by adsorption experi-ments as a function of the initial metal ion concentrations in aqueous solution under equilibrium time and pH condi-tions given in Tables 3and 4.The results of each material and metal ion are presented in Fig.7(Langmuir)and Fig.8(Freundlich)and Table 5.c q ¼1Q max Âb þc Q maxð1Þln q ¼ln k þ1nln cð2ÞTable 3Adsorption equilibrium times of MSBs 2,5and 6MSB Equilibrium time (min)Cu 2+Cd 2+Pb 2+230304054040506404050Table 4pH of largest adsorption of MSBs 2,5and 6MSB pH of largest adsorption Cu 2+Cd 2+Pb 2+2 5.5–6.0 6.5–7.5 5.0–6.05 5.5–6.0 6.5–7.5 5.0–6.065.5–6.06.5–7.55.0–6.0O.Karnitz Jr.et al./Bioresource Technology 98(2007)1291–12971295where q(mg/g)is the concentration of adsorbed metal ions per gram of adsorbent,c(mg/L)is the concentration of metal ion in aqueous solution at equilibrium,Q max and b are the Langmuir equation parameters and k and n are the Freundlich equation parameters.High correlation coefficients of linearized Langmuir and Freundlich equations indicate that these models can explain metal ion adsorption by the materials satisfactorily. Therefore,both models explained metal ion adsorption by MSBs2,5,and6as can be observed in Table5,with the exception of the Freundlich model for Pb2+adsorption by MSB2.The Langmuir isotherm parameter Q max indicates the maximum adsorption capacity of the material,in other words,the adsorption of metal ions at high concentrations. It can be observed in Table5that MSB5presents the larg-est Cu2+adsorption capacity while MSB6adsorbs Cd2+ and Pb2+the ngmuir parameter b indicates the bond energy of the complexation reaction of the material with the metal ion.It can be observed that MSB2presents the largest bond energy for Cu2+and Cd2+,while three materials do not differ significantly for Pb2.The Freundlich isotherm parameter k indicates the adsorption capacity when the concentration of the metal ion in equilibrium is unitary,in our case1mg/L.This parameter is useful in the evaluation of the adsorption capacity of metal ions in dilute solutions,a case closer to the characteristics of industrial effluents.The values of k of MSB2and5are much similar for Cu2+and Cd2+ and much higher than that for MSB6.This shows the superiority of both materials in the adsorption of these metal ions in low concentrations.MSB5has a higher k value for Pb2+when compared to those of the other materials.These results were compared with those of Vaughan et al.(2001)for a commercial macroreticular chelating resin with thiol functional groups,Duolite GT-73.The Q max of Duolite GT-73for Cu2+,Cd2+,and Pb2+were 62mg/g,106mg/g,and122mg/g,respectively.Duolite GT-73exhibited Q max lower than those of MSBs(Table5).4.ConclusionsThrough a fast,effective,and cheap methodology,it was possible to devise a strategy to introduce chelating func-tions(carboxylic acid and amine)to sugarcane bagasse. Modified sugarcane bagasses presented a good adsorption capacity for Cu2+,Cd2+,and Pb2+ions with maximum adsorption capacity observed for MSB6.It has been dem-onstrated that metal ion adsorption efficiency is propor-tional to the number of amine functions introduced into the material.MSB2,which contained only carboxylate functions,showed an efficiency similar to that of MSB5, a material of much more complex synthesis. AcknowledgementsWe thank FAPEMIG forfinancial support,CAPES and UFOP.Table5The Langmuir and Freundlich parameters for Cu2+,Cd2+and Pb2+ adsorptionMetalion MSB Langmuir FreundlichQ max (mg/g)b(L/mg)r2k(mg/g)n r2Cu2+21140.431191.623.90.919351390.1730.999898.315.80.906161330.0140.992722.8 3.640.9635Cd2+21960.1030.993459.4 4.160.977351640.0680.995762.8 5.490.983463130.0040.9528 5.15 1.630.9856Pb2+21890.1100.994566.0 4.660.757951890.1250.999914724.510.98163130.1210.9994121 5.210.8771296O.Karnitz Jr.et al./Bioresource Technology98(2007)1291–1297ReferencesAcemiog˘lu,B.,Alma,M.H.,2001.Equilibrium studies on adsorption of Cu(II)from aqueous solution onto cellulose.Journal of Colloid and Interface Science243,81–83.Ali,A.A.,Bishtawi,R.,1997.Removal of lead and nickel ions using zeolite tuff.Journal of Chemical Technology and Biotechnology69, 27–34.Baird,C.,1995.Environmental Chemistry.W.H.Freeman and Company, New York.Bianchi,A.,Micheloni,M.,Paoletti,P.,1991.Thermodynamic aspects of the polyazacycloalkane complexes with cations and anions.Coordi-nation Chemistry Reviews110,17–113.Caraschi,J.C.,Campana,S.P.,Curvelo, A.A.S.,1996.Preparac¸a˜o e Caracterizac¸a˜o de Polpas Obtidas a Partir de Bagac¸o de Cana de Ac¸u´car.Polı´meros:Cieˆncia e Tecnologia3,24–29.Gellerested,F.,Gatenholm,P.,1999.Surface properties of lignocellulosic fibers bearing carboxylic groups.Cellulose6,103–121.Gurnani,V.,Singh,A.K.,Venkataramani,B.,2003.2,3-Dihydroxypyri-dine-loaded cellulose:a new macromolecular chelator for metal enrichment prior to their determination by atomic absorption spectrometry.Analytical and Bioanalytical Chemistry377,1079–1086. Ho,Y.S.,Chiu,W.T.,Wang,C.C.,2005.Regression analysis for the sorption isotherms of basic dyes on sugarcane dust.Bioresource Technology96,1285–1291.Kelter,P.B.,Grundman,J.,Hage,D.S.,Carr,J.D.,Castro-Acun˜a,C.M., 1997.A discussion of water pollution in the United States and Mexico;with High School Laboratory Activities for the analysis of lead, atrazine,and nitrate.Journal of Chemical Education74,1413–1421. Krishnan,K.A.,Anirudhan,T.S.,2002.Removal of mercury(II)from aqueous solutions and chlor-alkali industry effluent by steam activated and sulphurised activated carbons prepared from bagasse pith:kinetics and equilibrium studies.Journal of Hazardous Materials92,161–183. Martell, A.E.,Hancock,R.D.,1996.Metal complexes in aqueous solutions.Plenum,New York.Navarro,R.R.,Sumi,K.,Fujii,N.,Matsumura,M.,1996.Mercury removal from wastewater using porous cellulose carrier modified with polyethyleneimine.Water Research30,2488–2494.Orlando,U.S.,Baes,A.U.,Nishijima,W.,Okada,M.,2002.Preparation of chelating agents from sugarcane bagasse by microwave radiation as an alternative ecologically benign procedure.Green Chemistry4,555–557.Panday,K.K.,Gur,P.,Singh,V.N.,1985.Copper(II)removal from aqueous solutions byfly ash.Water Research19,869–873. Vaughan,T.,Seo,C.W.,Marshall,W.E.,2001.Removal of selected metal ions from aqueous solution using modified corncobs.Bioresource Technology78,133–139.Xiao,B.,Sun,X.F.,Sun,R.,2001.The chemical modification of lignins with succinic anhydride in aqueous systems.Polymer Degradation and Stability71,223–231.O.Karnitz Jr.et al./Bioresource Technology98(2007)1291–12971297。

a rXiv:h ep-e x /5596v13Ma y25Measurement of the Higgs Boson Mass with a Linear e +e −Collider P .Garcia-Abia,CIEMAT,Madrid W.Lohmann and A.Raspereza DESY February 5,2008Abstract The potential of a linear e +e −collider operated at a centre-of-mass energy of 350GeV is studied for the measurement of the Higgs boson mass.An integrated luminosity of 500fb −1is assumed.For Higgs boson masses of 120,150and 180GeV the uncertainty on the Higgs boson mass measurement is estimated to be 40,65and 70MeV ,re-spectively.The effects of beam related systematics,namely a bias in the beam energy measurement,the beam energy spread and the luminosity spectrum due to beamstrahlung,on the precision of the Higgs boson mass measurement are investigated.In order to keep the systematic uncertainty on the Higgs boson mass well below thelevel of the statistical error,the beam energy measurement must be controlled with a relative precision better than 10−4.1IntroductionIn the Standard Model [1]particles acquire mass due to spontaneous sym-metry breaking by introducing a doublet of complex scalar fields.This so called Higgs mechanism [2]leads to one scalar particle,the Higgs boson.The mass of the Higgs boson is a free parameter of the Standard Model and of fundamental nature.If the Higgs boson exists,the Large Hadron Collider at CERN will be able to discover it [3].Precision measurements of the Higgs boson parameters and the exploration of the complete Higgs boson profile will be one of the central tasks at a future linear e +e −collider.In this article we study the potential of a future e +e −collider for the measurement of the mass of a relatively light Higgs boson,in the massrange from120to180GeV,and investigate possible systematic effects in-fluencing the precision of this measurement.The analysis presented ex-tends previous studies on the measurement of the mass of a light Higgs boson[4]and complements recent studies on the determination of reso-nance parameters of the Higgs boson with the mass in the range from200 to320GeV at a future linear e+e−collider[5].2Experimental Conditions and Detector Simu-lationsThe study is performed for a linear collider operated at a centre-of-mass energy,√p t=7·10−5·p t,(1) where p t is the transverse momentum in GeV/c.The energy resolutions of the electromagnetic and hadron calorimeters are:σE e√Eh =50%E h⊕4%,(2)where E e and E h are the energies of electrons and hadrons in GeV.Thepolar angular coverage of the central tracker maintaining the resolution is|cosθ|<0.85,above this range the tracking resolution deteriorates.The electromagnetic and hadron calorimeters cover|cosθ|<0.996maintain-ing the resolution over the whole angular range.The simulation of the detector is done using the SIMDET[7]package.The event reconstruction is done in terms of particleflow objects.First,tracks are measured with the tracking system and associated to calorime-ter clusters to define charged particleflow objects of electrons,muons and charged hadrons.Since the momentum measurement by the tracking sys-tem is much more accurate than the angular and energy measurements with calorimeters,the tracking information is used for the determination of the four-momentum of charged particles.Calorimetric clusters with no associated track are regarded as neutral particleflow objects originatingfrom photons and neutral hadrons.Measurements of the four-momentum of neutral objects are solely based on the calorimetric information.3Physics Processes√At a centre-of-mass energy oftopology150GeVZH→ℓ+ℓ−q¯q,ZH→ℓ+ℓ−gg8.80.06 ZH→q¯q q′¯q′,ZH→q¯q gg91.90.62 ZH→ℓ+ℓ−WW,W→q¯q′0.6 2.6ZH→q¯q WW,W→q¯q′ 6.026.6 ZH→ℓ+ℓ−ZZ,Z→q¯q0.080.17 ZH→q¯q ZZ,Z→q¯q0.82 1.73123.7s=350GeV.Also given is the total cross section for e+e−→ZH.The cross sections are calculated with PYTHIA taking into account initial state radiation.For background estimations events are generated with PYTHIA for the processes e+e−→q¯q(γ),e+e−→W+W−,e+e−→Z(γ∗)Z(γ∗)and e+e−→γ∗γ∗e+e−→f¯fe+e−.Six fermionfinal states resulting from the triple gauge boson production are generated with the WHIZARD package[9].The cross sections of the main background reactions are given in Table2.The numbers of events generated for each background channel as well as the number of generated signal events correspond to an integrated luminosity of500fb−1.Initial state radiation is simulated by PYTHIA.Beamstrahlung is taken into account using the CIRCE program[10].background process events4.0×1062.7×1041.3×1041.0×10313.20.48sinθ.(3)The resolutions of the jet energies and angular measurements are obtained from a Monte Carlo study using the sub-detector resolutions from Equa-tions(1)and(2).They are parameterized as:σE/E=30%E,σθ=15mrad,σφ=σθsignal and background distributions.The shape of the signal distribution is derived from a high statistics Monte Carlo sample of signal events andkeptfix in thefit.Free parameters are the peak value and the normalisa-tion factor of the signal distribution.4.1The ZH→ℓ+ℓ−q¯q and ZH→q¯q q′¯q′Final StatesThesefinal states are characterized by two isolated leptons and two jetsor by four jets and have the full energy deposited in the detector.Hence, events where the total energy visible in the detector is less that80%of thecentre-of-mass energy are rejected.Global event characteristics are used for the signal selection.For the channel ZH→ℓ+ℓ−q¯q,the number of reconstructed particlesmust be greater than20,the event thrust,T,must be less than0.85and the absolute value of the cosine of the polar angle of the thrust vector,cosθT,must be less than0.9.Electrons are identified as energy deposits in the electromagnetic calorimeter whose shape is compatible with the expecta-tion for an electromagnetic shower and with a matched track in the centraltracker.The measured track momentum and shower energy must be in agreement within5%and the shower leakage into the hadron calorimetermust be less than2GeV.Muons are tracks pointing to energy depositsin the calorimeters which are consistent with the expectation for a mini-mum ionizing particle.A pair of electrons or muons with opposite chargeis required.Both electrons and muons must have momenta larger than 10GeV/c and fulfill the polar angle cut|cosθℓ|<0.9.Leptons must satisfy isolation criteria,meaning that there are no other particles reconstructedwithin a15o cone with respect to the lepton momentum vector.The in-variant mass of a pair of leptons must be compatible with the mass of theZ boson within10GeV.These criteria reduce the backgrounds listed in Table2in the selected sample to the level of a few%with the exception of the process e+e−→ZZ.A cut on the polar angle of the momentum vector of the di-electron or di-muon system,|cosθℓℓ|<0.9,further suppresses the ZZ background.The signal selection efficiency is about45%.All recon-structed particles,except the two isolated leptons,are grouped into two jets using the Durham[11]jet clustering algorithm.Event selection for the ZH→q¯q q′¯q′channel is performed by requiringthe number of reconstructed particles to be larger than40,T<0.85and |cosθT|<0.8.No isolated leptons with an energy greater than10GeV are allowed.Reconstructed particles are grouped into four jets using the Durham jet clustering algorithm.Events are retained if the jet resolution parameter,for which the event is resolved from the four-to three-jet topol-ogy,y34,fulfill the relation log(y34)>−5.The selected events of bothfinal states are subject to a kinematicfit[12] imposing energy and momentum conservation.The kinematicfit is per-formed by varying the lepton momenta and angles within their resolu-tions given by Equations(1)and(3),respectively.The jet energies and an-gles are varied within the corresponding resolutions given by Equations(4).For events selected as ZH→ℓ+ℓ−q¯q,energy and momentum conserva-tion results in four constraints(4Cfit).Since the experimental resolutionin the invariant mass of the di-lepton system is much smaller than the nat-ural width of the Z boson,no constraint is applied in the kinematicfit to force the di-lepton mass to m Z.The di-jet invariant mass spectra after the4Cfit are shown in Figure1for m H=120GeV and150GeV,respectively. Clear signals are seen on top of the remaining smooth background frome+e−→ZZ.Also shown are the contributions from H→WW and H→ZZ decays to the signal.These are negligible for m H=120GeV but amount to 62%and5%,respectively,of the signal for m H=150GeV.The masses obtained from thefits equal the generated Higgs boson masses and have errors of85MeV for m H=120GeV and100MeV for m H =150GeV.For the4-jetfinal states,in addition to the four constraints from energy and momentum conservation,the invariant mass of the two jets assigned to the Z boson decay is constrained to m Z.Hence,a5Cfit is performed for all possible di-jet pairings.The pairing with the minimalχ2is chosen. In addition,thisχ2must be less than70.The signal selection efficiency is about25%,however the remaining event sample contains consider-able background from e+e−→ZZ,e+e−→W+W−and e+e−→q¯q(γ).The signal-to-background ratio is enhanced using the identification of b-quark jets.The ZVTOP[13]topological vertexfinder adapted for the pixel micro-vertex detector[6]is used to search for secondary vertices inside jets and determine mass,momentum and decay length of the vertex.In addition, the impact parameter joint probability[14]and the two highest impact pa-rameter significances are used as input into neural networks trained with jets containing no,one and more than one secondary vertices.A jet b-tag variable is defined[15]as function of the neural network output x asf b(x)B(x)=boson mass is performed.As an example,the di-jet invariant mass distri-bution and thefitted function of the signal is shown in Figure3.The results for the Higgs boson masses are equal to the generated masses. The statistical errors are45MeV at m H=120GeV and170MeV at m H=150GeV.4.2The ZH→ℓ+ℓ−WW and ZH→q¯q WW Final StatesWe consider W-boson decays into two quarks,hence the topologies ofthesefinal states are two isolated leptons accompanied by four jets or six jets,respectively.The requirements for electron and muon identificationare the same as in the previous section.Although event selection is opti-mized specifically for the ZH→ℓ+ℓ−WW and ZH→q¯q WWfinal states, contributions from the ZH→ℓ+ℓ−ZZ and ZH→q¯q ZZ channels are alsotaken into account.Events are selected with an energy deposited in the detector of morethan80%of the centre-of-mass energy and a number of the reconstructed particles larger than40.Events of thefinal state ZH→ℓ+ℓ−WW must contain a pair of isolatedelectrons or muons with opposite charges.Furthermore,the event thrust and the polar angle of the thrust vector are used to suppress the dominant background from the WW and ZZfinal states.The values of the cuts areT<0.95and|cosθT|<0.95.Since the two leptons of ZH→ℓ+ℓ−WW originate from the Z decay,their invariant mass is required to be equalwithin10GeV to m Z.A cut on the polar angle of the di-lepton momentum vector,|cosθℓℓ|<0.9,further suppresses the ZZ background.Tracks and calorimetric energy deposits not stemming from the leptons are grouped into four jets using the Durham algorithm.The jet resolution parameter y34must satisfy log(y34)>−6.0.Then a4C kinematicfit is performed imposing energy and momentumconservation.Only events for which theχ2of the4Cfit is less than50are retained in the selected sample.The signal selection efficiency amounts to50%at m H=150GeV and60%at m H=180GeV.The4-jet invariant mass distributions after the kinematicfit are shown in Figure4for m H= 150GeV and180GeV.Thefit of the mass spectra in Figure4again results in mass values for the Higgs boson equal to the generated ones.The uncertainties of the masses amount to90and80MeV for m H=150GeV and m H=180GeV, respectively.The small background in this channel comes mainly from the semilep-tonic decays of pair produced Z bosons and triple gauge boson produc-tion,ZWW,with a leptonic Z decay.Events of the process ZH→ℓ+ℓ−ZZ constitute13%and6%of the signal in the selected sample for m H=150 and180GeV,respectively.The ZH→q¯q WW channel is selected by requiring T<0.9and|cosθT|<0.95.There must be no isolated leptons with an energy greater than 10GeV.The reconstructed particles are grouped into six jets using Durham jet algorithm.The jet resolution parameter,for which an event is resolved from the6-to5-jet topology,y56,must satisfy log(y56)>−8.Then a likeli-hood discriminant,L HZ,is defined using as input the number of particles reconstructed in an event,the polar angle of the thrust vector and the jet resolution parameters y34and y56.Events are accepted when the value ofthis discriminant is larger than0.9.As an example,Figure5shows the dis-tribution of L HZ for the signal events for m H=180GeV and the backgroundprocesses.The six jets are now grouped in three di-jet pairs following crite-ria which depend on the mass of the Higgs boson.For m H<2m W usually only one W is expected to be on the mass shell,while the other is producedwith a mass close to the difference between m H and m W.The quantity χ2=(m ij−m Z)2/σ2Z+(m kl−m W)2/σ2W+(m mn−m klmn+m W)2/σ2W∗is calculated for all possible di-jet combinations,where m ij is the invariantmass of the two jets assigned to the Z boson,m kl the invariant mass of two jets assigned to the on-shell W boson,m mn the invariant mass of two jets assigned to the off-shell W boson and m klmn the invariant mass of thefour jets assigned to decay H→WW∗.The quantitiesσ2Z,σ2W andσ2W∗are obtained from Monte Carlo studies as the convolution of the bosonicwidths and the mass resolutions and are estimated to be6,9and15GeV, respectively.For m H>2m W both W bosons are on shell.Hence all di-jet combinations are taken and the quantityχ2=(m ij−m Z)2/σ2Z+(m kl−m W)2/σ2W+(m mn−m W)2/σ2Wis calculated.The jet pairing with the smallest value ofχ2is chosen and subject of a kinematicfit imposing energy-momentum conservation andconstraining the mass of the two jets assigned to the Z boson to m Z.Events are selected into thefinal sample if theχ2of the5Cfit is less than30.In addition,thefitted mass of the jets originating from the on-shell W decaymust be equal to m W within20GeV in the event sample selected for m H= 150GeV.For m H=180GeV,the sum and the difference of thefitted masses of the two jet pairs assigned to a W decay must be between125GeV and185GeV and−20and20GeV,respectively.The signal selection efficiency amounts to about20%.The sample selected for m H=150GeV also contains5%signal from the ZH→q¯q q′¯q′final state.The distribution of the invariant mass of the4-jet system is shown in Figure6for m H=150GeV and180GeV,respectively.From thefit ap-proximating the signal by a Gaussian the uncertainties of the masses are 100MeV and150MeV for m H=150GeV and180GeV,respectively.The background in this channel originates from e+e−→W+W−,e+e−→ZZ and e+e−→q¯q(γ)final states,and from triple gauge boson production processes.Events of the process ZH→q¯q ZZ constitute9%and5%of thesignal in the selected sample for m H=150and180GeV,respectively.4.3Combined ResultsTable3summarizes the statistical accuracy on the determination of m H for the differentfinal states and their combination.It should be noted that considerable overlap exists in the selected samples of the ZH→ℓ+ℓ−q¯q and ZH→ℓ+ℓ−WW channels and of the ZH→q¯q q′¯q′and ZH→q¯q WW channels.Hence,the combination is performed only for the non-overlapping topologies which gives a minimal combined error on the Higgs boson mass.This is done using the formula:1,∆2i(m H)where∆is the combined error,whereas∆i is the error obtained in the i th channel.Decay mode150ZH→ℓ+ℓ−q¯q10045–ZH→ℓ+ℓ−WW90–1504070Table3:Uncertainties on the determination of the Higgs boson mass for m H=120,150and180GeV.The ZH→ℓ+ℓ−WW and ZH→q¯q WW chan-nels are used for the combination at m H=150GeV.5Beam Related Systematic EffectsWe have investigated the effect of a bias in the beam energy measurement, of the beam energy spread and of an uncertainty in the differential lumi-nosity spectrum on the measurement of the Higgs boson mass.The impact of a bias in the beam energy measurement is estimated bygenerating signal samples with both positron and electron beam energies√shifted with respect to the nominal value ofs=350GeV,the shift in the beam energy is expected to result in a shift in the measured Higgs boson mass.As an example Figure7shows the distributions offitted values of m H in the ZH→ℓ+ℓ−q¯q channel for shifts in the beam energies of+25MeV, zero MeV and−25MeV.In each of the three considered cases the distribu-tion of m H is obtained from200statistically independent signal samples.The shift obtained in thefit of m H corresponds roughly to the shift of the beam energy with opposite sign.In the range of beam energy shifts from -100to100MeV the shift in the Higgs boson mass is found to depend lin-early on the shift in the beam energy:δm H=−α·δE b,(5) withα=0.85for the ZH→q¯q q′¯q′channel,0.80for the ZH→q¯q WW chan-nel,and1.04for the ZH→ℓ+ℓ−q¯q and ZH→ℓ+ℓ−WW channels.Hence, in order to keep the systematic bias in m H well below its statistical error, the beam energy measurement must be controlled with a precision better than10−4.To estimate the impact of a beam energy spread,a Gaussian distribu-tion of the beam energy has been used for the generation of signal events. As an example,Figure8shows the reconstructed Higgs boson mass spec-trum for a sample of ZH→q¯q q′¯q′events for a1%energy spread for both electron and positron beams and the same distribution for afix beam en-√ergy ofin Figure9for nominal values of the parameters a i and for the parameter a0shifted by±10%from its nominal value.Figure10presents the corre-sponding Higgs boson mass spectra a the sample of ZH→ℓ+ℓ−q¯q events. An uncertainty of10%in the determination of the parameters a0results in a systematic uncertainty of about10MeV on the Higgs boson mass in the ZH→ℓ+ℓ−q¯q and ZH→q¯q q′¯q′channels.The same result is obtained for the other parameters.The uncertainty is reduced to about1MeV if the parameters a i are measured with an accuracy of1%.The same result is obtained for the study of the ZH→ℓ+ℓ−WW and ZH→q¯q WW channels. 6ConclusionThe potential of the future linear e+e−collider for the measurement of the Higgs boson mass is evaluated.Assuming an integrated luminosity of500 fb−1,the Higgs boson mass can be measured with a statistical accuracy ranging from40MeV to70MeV for m H between120GeV and180GeV.In order to keep the systematic uncertainty due to a bias of the beam energy measurement well below the statistical uncertainty,the beam energy mea-surement has to be controlled with a precision better than10−4.Under operational conditions envisaged for the TESLA machine,the beam en-ergy spread and uncertainty in the differential luminosity spectrum are found to have negligible effect on the Higgs boson mass measurement.7AcknowledgmentsWe would like to thank Prof.K.Desch for many helpful discussions and his continuous interest and support.References[1]S.L.Glashow,Nucl.Phys.22(1961)579;S.Weinberg,Phys.Rev.Lett.19(1967)1264;A.Salam,Elementary Particle Theory,edited by N.Svartholm(Almqvist and Wiksell,Stockholm,1968),p.367. [2]P.W.Higgs,Phys.Lett.12(1964)132,Phys.Rev.Lett.13(1964)508andPhys.Rev.145(1966)1156;F.Englert and R.Brout,Phys.Rev.Lett.13 (1964)321;G.S.Guralnik,C.R.Hagen and T.W.B.Kibble,Phys.Rev.Lett.13(1964)585.[3]ATLAS Collaboration,”ATLAS:Detector and Physics Performance Tech-nical Design Report,Volume2”,CERN-LHCC-99-15,ATLAS-TDR-15 (1999);CMS Collaboration,”CMS Technical Proposal”,CERN/LHCC/94-38 (1994).[4]P.Garcia-Abia and W.Lohmann,EPJdirect C2(2000)1,A.Juste,hep-ex/9912041.[5]N.Meyer and K.Desch,Eur.Phys.J.C35(2004)171.[6]F.Richard,J.R.Schneider,D.Trines and A.Wagner,”TESLA:TechnicalDesign Report”,DESY2001-01,ECFA2001-209,TESLA Report2001-023,TESLA-FEL2001-05(2001).[7]SIMDET V3.2,M.Pohl and H.J.Schreiber,DESY-99-030(1999).[8]PYTHIA V6.136,T.Sj¨ostrand,m.82(1994)74.[9]W.Kilian,WHIZARD1.24,LC Note LC-TOOL-2001-039(2001).[10]CIRCE V6,T.Ohl,m.94(1996)53.[11]S.Catani et al.,Phys.Lett.B269(1991)432;S.Bethke et al.,Nucl.Phys.B370(1992)310.[12]V.Blobel,”Constrained Least Squares and Error Propagation”,Ham-burg(1997).[13]T.Kuhl,Nucl.Instr.and Meth.A511(2003)221;D.Jackson,Nucl.Instr.and Meth.A388(1997)247.[14]R.Barate et al.,Phys.Lett.B401(1997)150.[15]K.Desch et al.,LC Note LC-PHSM-2004-006(2004).[16]K.M¨onig,LC Note LC-PHSM-2000-060(200).050100150200Mass of 4C fit [GeV ]E v e n t s /0.5G e V 0255075100Mass of 4C fit [GeV ]E v e n t s /0.5G e V Figure 1:The di-jet invariant mass from the ZH →ℓ+ℓ−q¯q final state after a 4C kinematic fit for m H =120GeV (top)and 150GeV (bottom).0500100015002000100110120130140150Mass of 5C fit [GeV ]E v e n t s / G e V without b-tagwith b-tagFigure 2:The distribution of the invariant mass of the two jets assigned to the Higgs boson decay in the ZH →q¯q q ′¯q ′final state without requirement on the b-tag and after requiring the values of the b-tag of two jets to be larger than 0.2.02505007501000Mass of 5C fit [GeV ]E v e n t s / G e V Figure 3:The invariant mass of the two jets assigned to the Higgs boson decay in the ZH →q¯q q ′¯q ′final state after the 5C kinematic fit for m H =020406080Mass of 4C fit [GeV ]E v e n t s /0.5G e V 020406080Mass of 4C fit [GeV ]E v e n t s /0.5G e V Figure 4:The 4-jet invariant mass from the ZH →ℓ+ℓ−WW final state after a 4C kinematic fit for m H =150GeV (top)and 180GeV (bottom).101010101010L HZE v e n t s / 0.05Figure 5:The distributions of the signal likelihood used to select H →WW →6-jet final states for m H =180GeV .Solid,dashed and dotted lines represent the background processes,ZH →q¯q WW and ZH →q¯q ZZ signals.The vertical line indicates the cut imposed on this quantity.0100200Mass of 5C fit [GeV ]E v e n t s /G e V 050100150200Mass of 5C fit [GeV ]E v e n t s /G e V Figure 6:The four jet invariant mass from the ZH →q¯q WW final state after a 5C kinematic fit for m H =150GeV (top)and m H =180GeV (bottom).m H [GeV ]E n t r i e s /0.04 G e V Figure 7:The spectrum of the fitted values of the Higgs boson mass as obtained from 200independent signal samples for the case when both electron and positron beam energies are overestimated by 25MeV (dotted histogram),when they are underestimated by 25MeV (dashed histogram)and when no shifts are introduced to the beam energies (solidhistogram).Mass of 5C fit [GeV ]E v e n t s / G e V Figure 8:Reconstructed Higgs boson mass spectrum in the sample of the ZH →q¯q q ′¯q ′events for the case of monochromatic beams (solid his-togram)and for the case of 1%Gaussian energy spread for both electron and positron beams (dashed histogram).Figure 9:The beam energy spectrum after beamstrahlung for nominal pa-rameters a i at √。

Vacuum Requirements for Steel DegassingDr Simon BruceApplications Technologist, BOC Edwards, Crawley UK+44 1293 603276simon.bruce@Metallurgical Plant and Technology International, June 2002, 44-46, ISBN0935-7254 SummaryVacuum degassing (VD) and vacuum oxygen decarburisation (VOD) are the main processes in secondary steel making. The large volumes of dissolved contaminant gases arising and the generation of metallic fines and oxide dust require robust, high-capacity pumping equipment. Today's advanced vacuum dry mechanical vacuum pumping systems are superior to previously-used systems in that they enable better dust handling, increased pumping speed, and reduced operational and maintenance costs.The need for advanced vacuum pump systemsInvestment in steel vacuum degassing processes, both in new plant and upgrades of existing plant, is continuing as steel companies see the opportunity to increase the value of their products by improving their quality and supplying more special steels. For reasons of economy these processes are usually conducted on large quantities of molten steel in very large plants, and consequently very large vacuum pumping capacities are usually required. These processes are potentially very dirty with large amounts of metallic fines and oxide dust being generated. Historically much vacuum degassing has been done using multiple steam ejector stages backed by hogging steam ejectors or large water ring pumps. These systems traditionally require a lot of maintenance, and consume extremely large and expensive amounts of steam, generated by substantial steam raising plant.Oil-sealed vacuum pumps have never been considered robust enough to offer a less expensive solution, but as pressure increases on steel companies to reduce both energy expenditure and plant maintenance they are now looking to dry mechanical vacuum pumping systems, with much better dust handling capabilities, to provide significant savings.Compared to steam ejector systems, dry mechanical vacuum systems offer clear savings in running costs, maintenance costs, and installation space, and also offer increased speed, flexibility, and overall productivity to steel degassing operations. Large Roots vacuum booster pumps designed for high dust tolerance are the major component of mechanical vacuum degassing systems.Steel degassing processesSteel degassing is an essential process in secondary steel-making. Its value is in its rapid and effective removal of dissolved contaminant gases from primary steel (principally hydrogen and carbon monoxide) and the reduction in dissolved carbon levels, resulting in higher quality, higher value steel product with more widespread applicability. The two main processes are vacuum degassing (VD) and vacuum oxygen decarburisation (VOD).Vacuum degassing (VD) The basic VD process usually lasts 15-20 minutes and is conducted at pressures in the region of 0.5torr/0.67mbar. Under these conditions much of the dissolved hydrogen and carbon monoxide gases in the liquid metal desorb into the atmosphere above the steel and are evacuated. This process can also assist with the removal of lighter, more volatile metal elements (Pb, Sn, As, Sb, Bi, etc.) and sulphur. Residual gas levels in the resulting steel can typically be as low as one ppm for hydrogen. Soft purging with argon at the end of the process can also reduce residual oxygen levels to below 15ppm.For VD, gas flows of many tens of kg/h air equivalent must be handled at 0.67mbar. This puts the pumping speed capacities required into the tens of thousands of m3/h as a minimum, and demands the use of very large, multi-stage pump sets based on Roots vacuum boosters.Vacuum oxygen decarburisation (VOD) The VOD process is used typically to reduce the carbon content of high chromium stainless steels while avoiding significant collateral losses of chromium by oxidation. It uses the injection of pure oxygen into the molten steel to ‘burn out’ dissolved carbon by high temperature conversion to carbon monoxide (CO) and carbon dioxide (CO2) which are then evacuated away. To avoid undue losses of chromium the process is usually conducted at pressures of around 60-150torr / 80-200mbar. Extremely large amounts of dust and fines can be generated by this process which may, or may not, be captured by large filtration systems. At these pressures the pumping speed capacities required are much less than for VD, however, large Roots vacuum boosters are still needed.Other Processes Similar vacuum processes requiring high capacity pumping are vacuum arc degassing (VAD) and vacuum induction degassing (VID) which use alternative forms of heating to achieve similar objectives.Pumping performance requirementsThe basic performance parameters and requirements in a typical steel degassing pump system are listed in Table 1.To meet these high speed vacuum pumping requirements, the system should use an adequate numbers of large high vacuum (HV) Roots booster pumps, staged correctly to achieve sufficient pumping speed while maintaining satisfactory pressure ratio across each stage. These should be backed by primary pumps of sufficient capacity.The selection of primary pumps for backing stages depends on the type and size of process, the available site facilities and any customer preferences as follows:Table 1process type VD & VOD or VD onlyheat mass (capacity) tonnes of liquid metalfurnace volume typ. 2-3m3 per tonnefurnace air leakage typ. up to 10kg/h (air@20o C)initial pump down time to VD typ. 5-7minsVD process pressure typ. 0.67mbar / 0.5torrVD suction capacity typ. 1-2 kg/h/tonne (air@20o C)typ. 1250-2500m3/h/tonneVD line diameter typ. 800-1000mmVD gas dust load to pump system typ. v. lowVD gas temperature to pump system should be <= 60o CVOD process pressure typ. 80-200mbar / 60-150torrVOD suction capacity variableVOD line diameter typ. 800-1000mmVOD gas dust load to pump system can be high if filtration is poorVOD gas temperature to pump system should be <= 60o CBacking pump optionsFor VD processes the general requirement for backing is to provide reliable and adequate pumping speed at pressures in the region 10-50mbar (7.5-37.5torr).For VOD processes the requirement for backing is to provide reliable, high pumping speed in the region 200-400mbar (150-300torr), and to be able to tolerate reasonable levels of dust and contaminants.Dry pump sets Dry pump sets such as medium sized Roots boosters and dry claw primary pumps provide good backing speed to HV booster stages for VD operation (i.e. provide good pumping speed in the 10-50mbar region) and will also have excellent abilities to handle abrasive dusts, even in the high amounts which can arise from the VOD process. Much positive operating experience has been achieved with claw pumps even with severe dust loads on steel degassing plants, demonstrating simplicity of operation with high reliability. However, for larger sized plants a larger set of dry backing pumps is clearly needed, and economics may dictate that other backing options may need to be considered.Liquid ring pumps (LRPs) Large LRPs (or WRPs - water ring pumps) are a very economic and reliable way to generate fast roughing and high capacity backing for large sets of HV boosters. They are well accepted in the steel industry as simple, reliable pumps for hogging and higher pressure processes (e.g. VOD), and have been a standard alternative for steam ejectors in these duties for many years. They are inherently quite tolerant of process dust and dirt since these are largely absorbed and flushed out with the seal water.LRPs have a vaned rotor eccentrically mounted (slightly high) in a partially flooded horizontal cylindrical stator, driven by a suitably large motor. On start-up, the centrifugal action of the rotor rapidly establishes a circular liquid ring around the shell of the stator, with more gas space on the low side than on the high side. Vents in the lower side plates allow gas to be drawn in by the circulating rotor, which is then compressed on the high side by the liquid ring and vented out via non-return flapper valves in the upper side plates. The exiting gas is separated from entrained seal liquid which can then be recycled.However, there are two major drawbacks associated with the use of water sealed LRPs for steel degassing.1) the seal water consumption is large:-A typical 4,200 m3/h LRP may consume up to 10m3/h water in standard operation (50% recycled) or 20m3/h water in ‘once-through’ mode (i.e. no water recycling) and this water will exit straight to the waste water treatment plant. The incoming seal water must be clean but the effluent can be very contaminated by steel degassing processes - potentially a significant environmental consequence. The manufacturer may recommend once-through mode for VOD processes to minimise abrasion and wear inside the pump.2) the seal water temperature limits the ultimate achievable:-Seal water temperature is critical to LRP performance. This is of special concern for VD backing where the LRP must achieve a good ultimate vacuum to avoid stressing the stage three HV boosters (i.e. causing excessive pressure ratio). LRP manufacturers' specifications are usually based on 15o C seal water temperature which can be quite unrealistic, and care must be taken to establish the expected performance with the actual water temperature limits for the application (consult manufacturer's charts or ask specifically). As the seal water temperature increases so does its vapour pressure which impairs the LRPs vacuum pumping speed and also begins to cause cavitation (vapour bubble ‘explosions’) within the LRP as the inlet pressure drops towards ultimate. Although many manufacturers incorporate anti-cavitation devices, the net result is significant loss of pumping speed, cavitation noise/vibration, and especially a poorer ultimate pressure. Where this would have a critical and unacceptable impact on VD performance this must be dealt with by one or more of the following:-use once-through water (a likely requirement anyway)-chill the seal water (high plant and energy cost - may not be economic)-add an air ejector stage in front of the LRP (can be fed from the exhaust - but not liked by some operators)-add a small Roots booster stage in front of the LRP (adds cost and complexity) Large dry exhausters Big roughing capacity at proportionately lower cost than with other dry pumps can also be provided using large dry exhausters, i.e. Roots blowers specifically designed to vent to atmosphere and provide very high pressure differentials safely. As single units, exhausters usually have a much poorer ultimate vacuum than LRPs (typically limited to 200mbar / 150torr) and so for steel degassingduties two stage exhauster sets are needed. The ultimates of these sets are better than those of LRPs.The big advantages of dry exhausters compared to LRPs are minimal water consumption (only small quantities needed for cooling) and no major waste water disposal problem, no performance dependence on water temperature, and a good, reliable ultimate pressure. However, they are more expensive than LRPs (may be double prime cost) and typically require more installation space. Noise levels of large exhauster sets can also be very high (e.g. up to 100dBa without muffling).Typical Steel Degassing ExampleA modern steel degassing plant of nominal 75tonne heat capacity is designed for vacuum degassing (VD) at 0.67mbar and vacuum oxygen decarburising (VOD) in the region of 200mbar. The vacuum system specification is 100,000m3/h at 0.67mbar for VD and also 12,000m3/h at 200 mbar. Specifically for the VOD process a large cyclone/bag filtration system is installed upstream of the vacuum system.To achieve approximately 100,000m3/h for VD may require four 30,000m3/h HV boosters on the front row (stage 1), backed by two 14,000m3/h HV boosters as stage 2. The third stage would be a pair of 11,000m3/h HV boosters, typically backed by two large LRPs.Using only the stage 3 HV boosters, plus the LRPs, a reasonably high pumping speed at 200mbar can be achieved for the VOD process. The typical system speed curve is shown in Figure 1.Vacuum systems for VD and VOD of this nature can be considered in a modular arrangement, with the number of "modules" required dependant on the size of the steel degassing plant. Figure 2 shows a basic standard steel degassing module conceptwhich provides approximately 50,000m3/h pumping speed at 0.67mbar for VD and approximately 6,500m3/h at 200mbar for VOD.Figure 2。

a r X i v :h e p -p h /0611240v 2 17 J u l 2007OCHA-PP-267hep-ph/0611240Decay of Charged Higgs boson in a scenario of SUSYbreaking inspired neutrino massGi-Chol Cho a ),Satoru Kaneko a )∗and Aya Omote b )a )Department of Physics,Ochanomizu University,Tokyo 112-8610,Japanb )Graduate School of Humanities and Sciences,Ochanomizu University,Tokyo,112-8610,JapanAbstractIn some class of supersymmetric models,small neutrino mass is given as a consequence of the supersymmetry (SUSY)breaking.Phenomenologically interesting features of this scenario are as follows:(i)the right-handed sneutrino mass could be as low as TeV scale due to the Giudice-Masiero mechanism,and (ii)a scalar trilinear interaction of Higgs-slepton-(right-handed)sneu-trino could be sizable without suppression by the small neutrino Yukawa coupling.We study some phenomenological aspects of this scenario focusing on the scalar trilinear interaction.We show that the 1-loop correction by sneutrino exchange to the lightest Higgs boson mass destruc-tively interferes with top-stop contributions in the minimal SUSY Standard Model.We find that a decay of charged Higgs boson into sneutrino and charged slepton is sizably enhanced and hence it gives rise to a distinctive signal at future collider experiments in some parameter space.1IntroductionSmallness of neutrino mass is one of the important clues to physics beyond the Standard Model(SM).An attractive explanation on the origin of small neutrino mass is the seesaw mechanism[1].In the seesaw mechanism,a heavy right-handed neutrino is introduced and it couples to SU(2)L doublet neutrino and Higgs boson through the Yukawa coupling Yν.After diagonalizing the neutrino mass matrix,a smaller mass eigenvalue of neutrino, mν,is given bymν≃(Yνv)2/m N,(1) where m N and v are the mass of right-handed neutrino and the vacuum expectation value (v.e.v.)of the Higgs boson,respectively.If the Yukawa coupling Yνis of order unity, the right-handed neutrino should be heavy enough,say,m N∼1011GeV/(mν/1eV),tobe consistent with results of neutrino experiments.Then one may complain the large hierarchy between the scale of the seesaw mechanism(m N)and the electroweak scale (v).Furthermore it is hopeless to confirm the seesaw mechanism through searching for the right-handed neutrino at collider experiments(a trial to test the seesaw mechanism with hypothetical outcome of future experiments is proposed in ref.[3]).Thus it may be worth considering a possibility to lower the scale of seesaw mechanism(scale of right-handed neutrino)as low as testable at collider experiments,say,O(100GeV−1TeV),or alternative to the seesaw mechanism from a phenomenological point of view.It has been argued possibilities to explain the small neutrino mass as a consequence of supersymmetry(SUSY)breaking in refs.[4,5,6].Some phenomenologically viable points of this class of models are(i)light(TeV scale)right-handed sneutrino due to the Giudice-Masiero mechanism[7]and(ii)enhancement of scalar trilinear interaction among the right-handed sneutrino,left-handed slepton and Higgs bosons.Both(i)and (ii)can be,for example,realized as follows.Let usfirst introduce a chiral superfield X which is a SM gauge singlet but charged under a certain global symmetry.This global symmetry may allow non-renormalizable operators such asXX†LH u N,(3)M Pwhere dimensionless couplings with O(1)magnitude are suppressed.In(2)and(3),L and N denote the left-handed lepton and right-handed neutrino superfields,respectively.2The Higgs superfield with the hypercharge Y=1/2is represented by H u,and M P is the reduced Planck mass.Suppose that the F-component of the Xfield develops a v.e.v.F ∼m3/2M P due to the SUSY breaking,where m3/2is the gravitino mass.Then the D-component of(2)leads to the right-handed sneutrino mass asXX†LH u N F→Aν ℓH u νR.(5)M PNote that both m νR and Aνare of order the gravitino mass∼O(TeV).Moreover the scalar trilinear interaction is not suppressed if a dimensionless coupling in(3)is of order unity.In the minial SUSY SM(MSSM),the SUSY breaking scalar trilinear interactions of squark or sleptons are parametrized by A f Y f,where A f and Y f are the scalar trilinear coupling and the Yukawa coupling forflavor f,respectively.The scalar three-point vertices are,therefore,suppressed by small Yukawa couplings for thefirst two generations of squarks and sleptons.In the models of refs.[4,5,6],however,the scalar trilinear interaction of the right-handed sneutrino is not suppressed by the neutrino Yukawa coupling,as mentioned above.A few comments on this class of models are in order.In a series of non-renormalizable operators((2),(3),etc),there are lepton-number violating operators in general.If such operators are forbidden by an appropriate discrete symmetry,the seesaw mechanism does not work and the Dirac neutrino mass should be given by(3)with the A-component v.e.v. A of the X-field.Then,to satisfy the experimental limit,a relation A ≪of charged Higgs boson[4].Owing to Aν,the decay of charged Higgs boson into the sneutrino and selectron could be enhanced as compared to the MSSM.Wefind that,in some parameter space,the branching ratio of this decay mode can be as large as10%, and it may be detectable at future linear collider experiments.In our study,we neglect the generation mixing in both the left-and right-handed sneutrinos for simplicity.Al-though this scenario has a possibility if the neutrino is Majorana or Dirac,our study is available in both cases if the SUSY breaking B-term of sneutrino in the Majorana case is assumed to be small enough so that,in addition to suppress the1-loop correction to the mass of lighter neutrino,the sneutrino mass matrix has common structure in both cases.2Mass and InteractionsWefirst review the sneutrino masses and interactions tofix our notation.When the SUSY breaking B-term of sneutrino is neglected,the mass matrix of sneutrinos in a basis of( νL, νR)is given byM2˜ν= m2 νL Aνv sinβAνv sinβm2 νR ,(6)m2 νL=m2L+1v2u+v2d≈246GeV.The mass matrix(6)can be diagonalized using an unitary matrix U ν:U ν †M2 νU ν=diag(m ν1,m ν2),(m ν1<m ν2).(8)In the MSSM,the sneutrino mass is given by(7).Note that m2 νL(7)satisfies the following relation with the mass of left-handed selectron e L due to the SU(2)L symmetry:m2˜eL−m 2˜νL=(−1+s2W)m2Z cos2β.(9)Since cos2β<1for tanβ>1,the mass of sneutrino in the MSSM is always smaller than the selectron mass when tanβ>1.On the other hand,the lighter sneutrino mass (8)is independent of the selectron mass and can be much lighter than the sneutrino in the MSSM.4Figure1:(a):The lighter sneutrino mass m ν1as a function of Aνfor tanβ=3.Three lines correspond to m e L=120GeV(solid),150GeV(dashed)and180GeV(dotted).The results are obtained by taking m2 νL=m2 νR.(b):The coupling Aνas a function of a ratio m2 νR/m2 νL for tanβ=3.In Fig.1(a),we show the lighter sneutrino mass m ν1as a function of Aνfor tanβ= 3.Three lines correspond to m e L=120GeV(solid),150GeV(dashed)and180GeV (dotted).For the right-handed sneutrino mass,we take m νR=m νL for convenience. Note that the mass m ν1at Aν=0corresponds to that in the MSSM.Thefigure tells us that the large left-right mixing of sneutrino which is induced by large Aν,makes a sneutrino much lighter than that in the MSSM.Fig.1(b)shows the trilinear coupling Aνas a function of m2 νR/m2 νL.Three lines correspond to different values of the selectron mass as Fig.1(a).The lighter sneutrino mass m ν1isfixed at80GeV.It can be seen from thefigure that the coupling Aνincreases when m2 νR/m2 νL is larger than one.Next we summarize the interaction Lagrangian of sneutrino,slepton and Higgs bosons.For simplicity we take a limit of large pseudo scalar mass m A.Then the light-est Higgs boson h can be approximately identified with the SM Higgs.The interaction Lagrangians of sneutrino-sneutrino-lightest Higgs boson( νi− νj−h)and sneutrino-slepton-charged Higgs boson( νi− ℓ−H−)are then given as follows:• νi− νj−h interaction:L=Aν i,j(U ν)∗1i(U ν)2j ν∗i νj h+h.c.(i,j=1,2),(10)5Figure2:(a)The lightest Higgs boson mass m h as a function of Aν.Each line correspond to combinations of tanβ=3,30and m e L=300,500GeV as indicated.The1-loop correction from the top-stop loop is evaluated following ref.[13]using the stop mass m t=1TeV.The Higgs mass m h at Aν=0corresponds to the MSSM prediction.(b) The ratio R h defined in eq.(17)as a function of Aν.• νi− ℓ−H−interaction:L=g νi ℓH− ν∗i ℓH++h.c.,(11)g νi ℓH−=Aνcosβ(U ν)∗2i−g2m W sin2β U ν ∗1i(i=1,2).(12) 3Sneutrino contribution to the lightest Higgs boson massIt is known that the lightest Higgs boson mass m h receives large1-loop corrections mainly from the top quark and the stop exchanging diagram[9,10,11].In the scenario of TeV scale νR with sizable Aν,the νL- νR-h interaction(10)could give a new contribution to the lightest Higgs boson mass at1-loop ing the renormalization group method used in ref.[10],we evaluate the sneutrino contribution to m h.Let us take the large limit of the SUSY breaking mass scale m SUSY so that physics below m SUSY is described by the Standard Model.Then the lightest Higgs boson mass m h is simply parametrized bym2h=λv2,(13) whereλis a quartic coupling in the Higgs potential.Note that the quartic coupling at the tree level,λtree,satisfies the SUSY relation1λtree=where g Y and g are the U(1)Y and SU(2)L gauge couplings,respectively.The radiative corrections to the quartic coupling λin the MSSM can be found in,for example,ref.[10].In thescenarioof large A ν,the interaction (10)gives rise to the sneutrino exchanging box diagram as the 1-loop correction to the quartic coupling λ.The sneutrino contribution,λ ν,can be evaluated asλ ν=−A 4ν(m 21−m 22)(m 23−m 24)m 21+m 23m 1+m 22+m 24m 2−m 21+m 24m 1−m 22+m 23m 2.(16)In Fig.2(a),we depict the A νdependence of the lightest Higgs boson mass m h .We also compare,in Fig.2(b),a ratio of the Higgs boson mass in our scenario and in the MSSM which is defined asR h ≡m h61m SUSY4<0.(18)The minus sign in r.h.s.of (18)is the origin that m h is lowered via the sneutrino contribution.Fig.2(b)shows that the negative contribution to m h from the sneutrino diagram is less than 5%for A ν<∼1TeV.4Decay of charged Higgs bosonNext we examine a decay H −→ ν+ ℓ,where H −stands for a charged Higgs boson.In particular,a case of ℓ= e could be a distinctive process of our scenario because that such 7process is strongly suppressed in the MSSM due to the electron Yukawa coupling.So, we consider only the case of ℓ= e in the following study.In the MSSM,it is known that, for m H−>∼200GeV,H−dominantly decays into the top and bottom quarks owing to the sizable Yukawa couplings(for a review of various decay channels of the charged Higgs boson in the supersymmetric models,see ref.[12]).Theτ+ντmode is subdominant for large tanβ(>∼10)due to the tau-Yukawa coupling.On the other hand,when Aνis sizable,it is expected that the decay mode H−→ ν1+ e is much enhanced in small tanβregion because that the decay vertex is proportional to Aνcosβ(12).The decay widthof H−→ ν1+ e is given as follows:Γ(H−→ ν1+ e)=1mH− 2 , m eIt can be seen from Fig.3that the branching ratio of H−→ ν+ ℓmode could be as large as10%for small tanβ(<∼7).In the MSSM,the charged Higgs boson can decay into νL and e R.For comparison,wefix the mass of e R as m e R=m e L=200GeV.Then the decay mode H−→ νL+ e R is kinematically forbidden because the sneutrino νL cannot be much lighter than e L due to the SU(2)L relation(9)(note that m e R=m e L=200GeV). Therefore,if the charged Higgs boson mass does not differ so much from the masses of charged sleptons,the decay H−→ νL+ e R in the MSSM is strongly suppressed. Next we study a signal of the decay H−→ ν1+ e L in some detail.For our choice of the inputs used in Fig.3,the selectron e L dominantly decays into the lightest neutralino and an electron, e L→ χ01+e.Then,since the branching ratio of the ν1+ e L mode is roughly10%for small tanβregion,a probability which wefind an electron from this decay mode can be estimated as Br(H−→ ν1+ e L)×Br( e L→e+ χ01)≃10%.The electron is also coming out from the W boson of the decay H−→W+h,and the chargino of the decay H−→ χ−+ χ0.From Fig.3wefind that Br(H−→W+h)<∼3% and the leptonic decay of the W boson is known as Br(W→ν+e)<∼10.8%[14].It leads to Br(H−→W+h)×Br(W→ν+e)<∼0.3%.In case of Fig.3(a),therefore, the background from H−→W+h is much suppressed.In case of H−→ χ−+ χ0,the branching ratio is Br(H−→ χ−+ χ0)is about1%and Br( χ−→e+ ν)is roughly30% per each leptonflavor.Thus Br(H−→ χ−+ χ0)×Br( χ−→e+ ν)is about0.3%.As shown in Fig.3(b),however,if the lighter chargino is dominantly gaugino,the branching ratio of the chargino-neutralino mode increases,so that the branching ratio of H−→ ν1+ e L is relatively decreased.In this case we estimate the probability that the electron is found in the χ−+ χ0mode of the charged Higgs decay as Br(H−→ χ−+ χ0)×Br( χ−→e+ ν)≃10%.This competes with the probability that an electron is coming out from the e L+ ν1decay.We conclude that,even in our specific choice of parameter set,the χ−+ χ0mode could be a serious background to search the decay H−→ ν1+ e L when the chargino and neutralino are almost gauginos.We would like to discuss the testability of the scenario of light νR with unsuppressed Aνat future collider experiments using the decay H−→ ν1+ e L→e+E T.An important point is to identify that the observed electron comes from H−.It could be achieved using the pair production of the charged Higgs bosons.In a pair production of the charged Higgs,one of the charged Higgs bosons can be identified using the t+b mode.Then if an electron is observed in the charged Higgs pair production it must be identified as one from the decay of another charged Higgs through H−→ ν1+ e L.For example,at the e+e−linear collider(ILC),the typical size of the cross section of the charged Higgs boson9Figure3:The branching ratios of charged Higgs boson decay for m H−=350GeV.Thedecay mode into sneutrino and selectron is found for m˜eL =200GeV,m˜ν1=50GeV,Aν=500GeV.The chargino-neutralino mode is obtained for m χ−1=150GeV with M2/µ=5 (a)and1(b).pair is O(1−10)(fb)for m H−=O(100GeV)[12].Assuming the integrated luminosity as100fb−1,it is expected that100∼1000charged Higgs pairs are produced in a year. Fig.3(a)tells us that,when tanβ=3,only few electrons appear from1000charged Higgs bosons in the MSSM(the W+h mode),while about160electrons from the e+ ν1 mode is expected in our scenario.Therefore,an excess of electrons from the charged Higgs decay could be a signal of the TeV scale right-handed sneutrino with unsuppressed trilinear coupling Aν.5SummaryIn this paper,we have studied phenomenology of the scenario of TeV scale right-handed sneutrino inspired by models of SUSY breaking inspired neutrino mass[4,5,6].The important prediction of this scenario is that the sneutrino trilinear coupling Aνcould be sizable and is not suppressed by the neutrino Yukawa coupling.We examined two phenomenological consequences of this scenario.We found that the sneutrino contribu-tion to the lightest Higgs boson mass is destructively interferes with the ordinary MSSM contributions.Thus the lightest Higgs boson mass may be lowered in this model via sneutrino exchange with large Aν.The large Aνalso affects the decay of charged Higgs boson.It is shown that the process H−→ ν1+ e L could be subdominant decay mode in some parameter region and the branching ratio is roughly∼10%for small tanβ.In10such parameter region,we expect that roughly200electrons per year from the charged Higgs decay at the ILC experiments with the integrated luminosity100fb−1.On the other hand the MSSM predicts only few electrons from the charged Higgs decay.The excess of the electrons in the charged Higgs decay,therefore,could be a signal of the TeV νR scenario.AcknowledgmentsThe work of G.C.C.was supported in part by the Grant-in-Aid for Science Research, Ministry of Education,Science and Culture,Japan(No.K175402386).The work of S.K. was supported by the Japan Society of Promotion of Science.References[1]P.Minkowski,Phys.Lett.B67,421(1977);T.Yanagida,in Proceedings of the work-shop on unified theory and baryon number in the universe,O.Sawata and A.Sug-amoto eds.,KEK report79-18,Tsukuba,Japan1979;M.Gell-Mann,P.Ramond and R.Slansky,Complex spinors and unified theories,in Supergravity,D.Z.Freed-man and F.van Nieuwenhuizen eds.,North Holland,Amsterdam1979.[2]M.Fukugita and T.Yanagida,Phys.Lett.B174,45(1986).[3]M.R.Buckley and H.Murayama,arXiv:hep-ph/0606088.[4]N.Arkani-Hamed,L.Hall,H.Murayama,D.Smith and N.Weiner,Phys.Rev.D64,115011,2001.[5]F.Borzumati and Y.Nomura,Phys.Rev.D64,053005(2001).[6]J.March-Russell and S.M.West,Phys.Lett.B593,181(2004).[7]G.F.Giudice and A.Masiero,Phys.Lett.B206,480(1988).[8]F.Borzumati,K.Hamaguchi,Y.Nomura and T.Yanagida,hep-ph/0012118.[9]Y.Okada,M.Yamaguchi and T.Yanagida,Prog.Theor.Phys.85,1(1991).[10]Y.Okada,M.Yamaguchi and T.Yanagida,Phys.Lett.B262,54(1991).[11]J.R.Ellis,G.Ridolfiand F.Zwirner,Phys.Lett.B257,83(1991);ibid.Phys.Lett.B262,477(1991);H.E.Haber and R.Hempfling,Phys.Rev.Lett.66,1815 (1991).11[12]A.Djouadi,hep-ph/0503173.[13]H.E.Haber,R.Hempfling and A.H.Hoang,Z.Phys.C75,539(1997).[14]W.M.Yao et al.[Particle Data Group],J.Phys.G33,1(2006).12。

a rXiv:h ep-ph/937293v119J ul1993CERN-TH.6951/93hep-ph/9307293Fabio Zwirner ∗Theory Division,CERN CH-1211GENEVE 23Switzerland THE SUSY WORLD Summary Talk of the Workshop ‘Properties of SUSY particles’Erice,September 28–October 4,1992.CERN-TH.6951/93July 1993As Fayet reminded us in his introductory talk1,realistic models of low-energy supersymmetry have been studied for more than15years.Atfirst sight,the absenceof direct experimental evidence does not match such an intense theoretical effort,and puts supersymmetry on the same footing as many other extensions of the StandardModel(SM).A number of theoretical and phenomenological reasons,however,makelow-energy supersymmetry particularly attractive with respect to its alternatives:the intense activity reported at this workshop is there to prove it!My attempt to summa-rize its highlights will be organized as follows.In Section1,I shall review the mainmotivations that lead most of us to consider the‘SUSY world’as a plausible scenario. The simplest realization of low-energy supersymmetry,the Minimal Supersymmetricextension of the Standard Model(MSSM),will be recalled,with some comments on possible non-minimal variations.Section2will summarize the phenomenology of super-symmetric particle searches,including Higgs bosons,at present and future accelerators.Finally,Section3will review some open theoretical problems connected with sponta-neous supersymmetry breaking in supergravity and superstring models,and draw someconclusions.Unavoidably,the selection of topics will depend on space limitations andon my personal view of the subject:I apologize in advance with the participants whose contributions would have deserved a better treatment.1.The MSSM:a paradigm for low-energy SUSY1.1.Theoretical motivationsAs discussed in the talks by Fayet1and Kounnas2,there are many good reasons tobelieve that four-dimensional supersymmetry and its local version,supergravity,could be relevant in a fundamental theory of particle interactions.In particular,superstringsare the present best candidates for a consistent quantum theory unifying gravity with allthe other fundamental interactions,and supersymmetry seems to play a very important role for the quantum stability of superstring solutions inflat four-dimensional space-time.Experimental data,however,tell us that supersymmetry is broken,but stringshave not yet given us any insight about the scale of supersymmetry breaking.The only motivation for low-energy supersymmetry,i.e.supersymmetry effec-tively broken around the electroweak scale,comes from the naturalness or hierarchy problem of the SM,whose formulation will now be sketched.Despite its remarkablephenomenological success,it is impossible not to regard the SM as an effective low-energy theory,valid up to some energy scaleΛat which it is replaced by some more fundamental theory.CertainlyΛis less than the Planck scale M P∼1019GeV,since one needs a theory of quantum gravity to describe physics at these energies.However,thestudy of the Higgs sector of the SM suggests thatΛshould rather be close to the Fermiscale,G−1/2F∼300GeV.The argument goes as follows.Consistency of the SM requires the SM Higgs mass to be less than O(1TeV).If one then tries to extend the validity of,one is faced with the fact that in the SM there is the SM to energy scalesΛ≫G−1/2Fno symmetry to justify the smallness of the Higgs mass with respect to the(physical) cut-offΛ.This is related to the existence of quadratically divergent loop corrections to the Higgs mass in the SM.Motivated by this problem,much theoretical effort has been devoted tofinding descriptions of electroweak symmetry breaking,which modify the.Here supersymmetry comes into play because of its improved SM at scalesΛ∼G−1/2Fultraviolet behaviour with respect to ordinary quantumfield theories,due to cancella-tions between bosonic and fermionic loop diagrams.If one wants to have a low-energy,with one or more elementary scalar effective Lagrangian valid up to scalesΛ≫G−1/2Ffields,kept light without unnaturalfine-tuning of parameters,the solution is to intro-duce supersymmetry,effectively broken in the vicinity of the electroweak scale.This does not yet explain why the scale M SUSY of supersymmetry breaking is much smaller thanΛ(further considerations on this problem will be made in thefinal section),butto the supersymmetry-breaking scale M SUSY,and at least links the Fermi scale G−1/2Fmakes the hierarchy G−1/2F∼M SUSY<<Λstable against radiative corrections.1.2.The MSSMThe most economical realization of low-energy supersymmetry is the MSSM, whose defining assumptions were recalled by Fayet1.The gauge group is G=SU(3)C×SU(2)L×U(1)Y,and the matter content corresponds to three generations of quarks and leptons,as in the SM.To give masses to all charged fermions and to avoid chiral anomalies,however,one is forced to introduce two complex Higgs doublets,one more than in the SM case.To enforce baryon and lepton number conservation in renormaliz-able interactions,one imposes a discrete R-parity:in practice,R=+1for all ordinary particles(quarks,leptons,gauge and Higgs bosons),R=−1for their superpartners (spin-0squarks and sleptons,spin-1/2gauginos and higgsinos).A globally supersym-metric Lagrangian L SUSY is then fully determined by the superpotential(in standard notation)f=h U QU c H2+h D QD c H1+h E LE c H1+µH1H2.(1) To proceed towards a realistic model,one has to introduce supersymmetry break-ing.In the absence of a fully satisfactory mechanism for spontaneous supersymmetry breaking at a fundamental level,it seems sensible to parametrize supersymmetry break-ing at low energy by a collection of soft terms,L soft,which preserve the good ultraviolet properties of global supersymmetry.This L soft contains mass terms for scalarfields and gauginos,as well as a restricted set of scalar interaction terms−L soft= i˜m2i|ϕi|2+1λAλA+ h U A U QU c H2+h D A D QD c H1+h E A E LE c H1+m23H1H2+h.c. ,(2) whereϕi(i=H1,H2,Q,U c,D c,L,E c)denotes the generic spin-0field,andλA(A= 1,2,3)the generic gauginofield.Observe that,since A U,A D and A E are matrices in generation space,L soft contains in principle a huge number of free parameters.More-over,for generic values of these parameters one encounters phenomenological problemswithflavour-changing neutral currents,new sources of CP violation,and charge-and colour-breaking vacua.All the above problems can be solved at once if one assumesthat the running mass parameters in L soft,defined at the one-loop level and in a mass-independent renormalization scheme,can be parametrized,at some grand-unificationscale M U,by a universal gaugino mass m1/2,a universal scalar mass m0,and a universaltrilinear scalar coupling A,whereas m23remains in general an independent parameter.1.3.Non-minimal modelsThe above assumptions,which define the MSSM,are plausible but not compul-sory:relaxing them leads to non-minimal supersymmetric extensions of the SM.For example,as discussed in the talks by Dreiner3and Kobayashi4,one can con-sider models in which R-parity is explicitly broken by some superpotential couplings. The acceptable ones have either the baryon or the lepton number violated by renormal-izable interactions among light particles,and give rise to phenomenological signaturesthat can be drastically different from the ones of the MSSM.A proof of this is the fact that,with some luck,one could be able to detect signals of supersymmetry even atHERA,which in the case of the MSSM cannot add much to what we already know.Another possibility is to enlarge the Higgs sector of the model,for example byadding a gauge-singlet Higgs superfield,as discussed in the talk by Kane5.In this casethe restrictions imposed by supersymmetry on Higgs masses and couplings are much weaker than in the minimal case.On the other hand,requiring perturbative unificationof couplings can still lead to interesting constraints,and in particular to an upperbound on the lightest Higgs mass of the order of150GeV.As for the boundary conditions at the unification scale,one can observe withIb´a˜n ez6that the simplest unification conditions on the gauge coupling constants are not really compulsory in string unification.In a general four-dimensional string modelwith gauge group SU(3)×SU(2)×U(1)×G,one can have tree-level relations suchas g1k1=g2k2=g3k3,where the integer numbers k a(a=1,2,3)are the so-called Kac-Moody levels.In string unification there is no fundamental reason for the tree-level prediction sin2θW≡(3/5)g21/[(3/5)g21+g22]=3/8,which is so successful when combined with the MSSM quantum corrections.Such an occurrence could be relatedto the existence of a gauge U(1)X symmetry of the Peccei-Quinn type,whose anomalyis cancelled by a Green-Schwarz mechanism,but no realistic string model with these properties has been found yet.Less radically,one can also consider the possibility of non-universal boundaryconditions on the soft supersymmetry-breaking terms.Such a possibility,which could be realized in string model-building(an example was given in the talk by Antoniadis7, others were recently discussed in Ref.8),is strongly constrained by the phenomenolog-ical limits onflavour-changing neutral currents,but would lead to modified relations among the low-energy parameters with respect to the MSSM case.All these non-minimal extensions remind us that we should not take the MSSM as the only viable paradigm for low-energy supersymmetry,and that experimental analy-ses should rather rely on the smallest possible amount of theoretical assumptions.On the other hand,non-minimal models typically increase the number of free parameters without correspondingly increasing the physical motivation,so we shall not discuss them further.1.4.Phenomenological virtues of the MSSMIt is perhaps useful,at this point in the discussion,to recall some phenomenolog-ical virtues of the MSSM(besides the solution of the‘technical’part of the hierarchy problem),which were mentioned at this workshop.As stressed in the talk by Haber9,an aspect that became particularly relevant after the recent precision measurements at LEP is the fact that electroweak data put little indirect constraints,via radiative corrections,on the MSSM parameters.In most of its parameter space,the MSSM predictions for electroweak observables coincide in practice with those of the SM for a relatively light Higgs.Deviations comparable to the present experimental accuracy can only occur for a light stop-sbottom sector with large mass splittings,or for a chargino with mass just above the production threshold at LEP I.This is not the case,for example,of technicolor and extended technicolor models,which are severely constrained by the recent LEP data.Another important property of the MSSM,discussed in the talks by Haber9and Wagner10,is related to the fact that the running top Yukawa coupling h t(Q)has an effective infraredfixed point,smaller than in the SM case.Neglecting mixing and the Yukawa couplings of the remaining fermions,h t obeys the following one-loop renormal-ization group equation(RGE)dh t8π2 −82g22−13Fig.1.The region of the(tanβ,m t)parameter space in which all running Yukawa couplings remainfinite at energy scales up toΛ=1016GeV(from Ref.9).parameter space.His results could be summarized as follows.In most of the otherwise acceptable parameter space,the LSP is cosmologically harmless,in the sense that its relic density is smaller than the closure density of the Universe.Moreover,in a small but non-negligible region of parameter space,the LSP relic density turns out to be large enough to be of cosmological interest in relation with the dark-matter problem. It is then conceivable,even if not very likely,that thefirst evidence for supersymmetry could come from the dedicated experiments searching for dark-matter signals!One of the most attractive features of the MSSM is the possibility of describing the spontaneous breaking of the electroweak gauge symmetry as an effect of radiative corrections,as discussed by Kounnas2and Lahanas12.It is remarkable that,starting from universal boundary conditions at the unification scale,it is possible to explain naturally whyfields carrying colour or electric charge do not acquire non-vanishing VEVs,whereas the neutral components of the Higgs doublets do.We give here a simplified description of the mechanism in which the physical content is transparent. The starting point is a set of boundary conditions on the independent model parameters at the unification scale Q=M U.One then evolves all the running parameters from the,according to the RGEs,and considers grand-unification scale to a low scale Q∼G−1/2Fthe renormalization-group-improved tree-level potentialV0(Q)=m21|H1|2+m22|H2|2+m23(H1H2+h.c.)+g28 |H2|2−|H1|2 2.(4)All masses and coupling constants in V0(Q)are running parameters,evaluated at the scale Q.The minimization of the potential in Eq.(4)is straightforward.To generate non-vanishing VEVs v1≡ H01 and v2≡ H02 ,one needsB≡m21m22−m43<0.(5) In addition,a certain number of conditions have to be satisfied to have a stable mini-mum with the correct amount of symmetry breaking and with unbroken colour,electric charge,baryon and lepton number:for example,all the running squark and slepton masses have to be positive.In the whole process,a crucial role is played by the top Yukawa coupling,which strongly influences the RGE for m22.For appropriate boundaryconditions,the RGEs drive B<0at scales Q∼G−1/2F ,whereas all the squark andslepton masses remain positive as desired,to give a phenomenologically acceptable breaking of the electroweak symmetry.1.5.Supersymmetric grand-unificationThe previous list has left out one of the most impressive arguments in favour of low-energy supersymmetry,i.e.the agreement of the generic predictions of supersym-metric grand unification with the extracted values of the gauge coupling constants at the electroweak scale.This topic has been discussed at great length by Zichichi13at this workshop,and I will try to give here my personal summary of the subject.Starting from the boundary conditiong3(M U)=g2(M U)=g1(M U)≡g U,(6) where g1=g2A(Q)=18π2logM U5,(8)whereas in the SMb03=−7,b02=−1910.(9)Starting from three input quantities at the electroweak scale,for exampleα3(m Z),α−1em(m Z)and sin2θW(m Z),one can perform consistency checks of the grand-unification hypothesis in different models.In the minimal SU(5)model15,and indeed in any other model where Eq.(6) holds and the light-particle content is just that of the SM(with no intermediate mass scales between m Z and M U),Eqs.(7)and(9)are incompatible with experimentaldata.This wasfirst realized by noticing that the prediction M U≃1014−15GeV is incompatible with the experimental data on nucleon decay.Subsequently,also theprediction sin2θW≃0.21was shown to be in conflict with the experimental data,and this conflict became even more significant after the recent LEP precision measurements.In the MSSM,assuming for simplicity that all supersymmetric particles havemasses of order m Z,one obtains16M U≃1016GeV(which increases the proton life-time for gauge-boson-mediated processes beyond the present experimental limits)and sin2θW≃0.23.At the time of Ref.16,when data were pointing towards a signifi-cantly smaller value of sin2θW,this was considered by some a potential phenomeno-logical shortcoming of the MSSM.The high degree of compatibility between data and supersymmetric grand unification became manifest only later17,after improved data on neutrino-nucleon deep inelastic scattering were obtained;it was recently re-emphasized18,13after the LEP precision measurements.One should not forget,however, that unification of the MSSM is not the only solution that canfit the present extracted values of the gauge coupling constants at Q=m Z:for example,non-supersymmetric models with ad hoc light exotic particles or intermediate symmetry-breaking scales could also do the job.The MSSM,however,stands out as the simplest physically mo-tivated solution.If one wants to make the comparison between low-energy data and the predictions of specific grand-unified models more precise,there are several factors that should be further taken into account.After the inclusion of higher-loop corrections and threshold effects,Eq.(7)is(schematically)modified as follows1g2U +b AQ+∆th A+∆l>1A(A=1,2,3).(10)In Eq.(10),∆th A represents the so-called threshold effects,which arise whenever theRGEs are integrated across a particle threshold,and∆l>1A represents the correctionsdue to two-and higher-loop contributions to the RGEs.Both∆th A and∆l>1A are scheme-dependent,so that one should be careful to compare data and predictions within the same renormalization scheme.The∆th A receives contributions both from thresholds around the electroweak scale(top quark,Higgs boson,and in SUSY-GUTs also the additional particles of the MSSM spectrum)and from thresholds around the grand-unification scale(superheavy gauge and Higgs bosons,and in SUSY-GUTs also theirsuperpartners).Needless to say,these last threshold effects can be computed only in the framework of a specific grand-unified model,and typically depend on a numberof free parameters.Besides the effects of gauge couplings,∆l>1A must include also theeffects of Yukawa couplings,since,even in the simplest mass-independent renormaliza-tion schemes,gauge and Yukawa couplings mix beyond the one-loop order.In mini-mal SU(5)grand unification,and for sensible values of the top and Higgs masses,allthese corrections are small and do not substantially affect the conclusions derived from the na¨ıve one-loop analysis.This is no longer the case,however,for supersymmetric grand unification.First of all,one should notice that the MSSM by itself does notuniquely define a SUSY-GUT,whereas threshold effects and even the proton lifetime (owing to a new class of diagrams19,which can be originated in SUSY-GUTs)becomestrongly model-dependent.Furthermore,the simplest SUSY-GUT20,containing only chiral Higgs superfields in the24,5and5Higgs supermultiplets,and cannot repro-duce correctly the observed pattern of fermion masses and mixing angles.Threshold effects are typically larger than in ordinary GUTs,because of the much larger numberof particles in the spectrum,and in any given model they depend on several unknown parameters.Also two-loop effects of Yukawa couplings can be quantitatively importantin SUSY-GUTs,since they depend not only on the top-quark mass,but also on the ratio tanβ=v2/v1of the VEVs of the two neutral Higgsfields:these effects become large for m t>∼140GeV and tanβ∼1,which correspond to a strongly interacting top Yukawa coupling.All these effects,and others,have been recently re-evaluated21.The conclu-sion is that,even imagining a further reduction in the experimental errors on the threegauge couplings,it is impossible to claim indirect evidence for supersymmetry and to predict the MSSM spectrum with any significant accuracy.The only safe statement is that,at the level of precision corresponding to the na¨ıve one-loop approximation,there is a remarkable consistency between experimental data and the prediction of supersym-metric grand unification,with the MSSM R-odd particles roughly at the electroweak scale.These conclusions are summarized in Fig.2,borrowed from Ref.22,which com-pares post-LEP and pre-LEP uncertainties,both theoretical and experimental,in the determination of sin2θW(m Z).At this point it is worth mentioning how the unification constraints can be applied to the low-energy effective theories of four-dimensional heterotic string models.The basic fact to be realized is that the only free parameter of these models is the string tension,whichfixes the unit of measure of the massive string excitations.All the other scales and parameters are related to VEVs of scalarfields,the so-called moduli, corresponding toflat directions of the scalar potential.In particular,there is a relation between the string mass M S∼α′−1/2,the Planck mass M P∼G−1/2N,and the unified coupling constant g U,which reflects unification with gravity and implies that in any given string vacuum one has one more prediction than in ordinaryfield-theoretical grand unification.In a large class of string models,one can write down an equationparison of theory and experiment in the determination of the electroweak mixing angle from the unification hypothesis,now and before LEP(from Ref.22).of the same form as(10),and compute g U,M U,∆th A,...in terms of the relevant VEVs23.In theνµ.Detection of nucleon decay in one of these channnels would certainly be a very strong argument in favour of supersymmetric grand unification.2.Supersymmetry searches2.1.The particle spectrum of the MSSMIn the R-even sector,the only new feature of the MSSM with respect to the SM is its extended Higgs sector,with two independent VEVs,v1≡ H01 and v2≡ H02 ,which can be taken to be real and positive without loss of generality.Quarks of charge2/3 have masses proportional to v2,quarks of charge1/3and charged leptons have masses proportional to v1.The W and Z masses are proportional toparameters only:a convenient choice is,for example,(m A,tanβ).Radiative corrections to Higgs masses and couplings,however,can be large,as we shall review later,and have to be taken into account in phenomenological analyses.In the R-odd sector of the MSSM,the spin-0fields are the squarks and the sleptons.Neglecting intergenerational mixing,and leaving aside the stop squarks for the moment,their masses can be easily calculated in terms of the fundamental parameters m0,m1/2and tanβ:m2˜f=m2f+˜m2f+m2D(˜f),(11)˜m2f=m20+C(˜f)m21/2,(12)m2D(˜f)=m2Z cos2β(T f3L−sin2θW Q f),(13) where,omitting generation indices,f=[q≡(u,u c,d,d c),l≡(ν,e),e c]and C(˜q)∼5−8,C(˜l)≃0.5,C(˜e c)≃0.15.Among the spin-1/2particles onefinds the strongly interacting gluinos,˜g,whose mass is directly related to the SU(2)and U(1)gaugino masses and to m1/2bym˜gα2≃M1αU,(14)whereα1≡(5/3)g′2/(4π)andαU is the gauge coupling strength at the grand unifi-cation scale.The weakly interacting spin-1/2particles are the SU(2)×U(1)gauginos (˜W±;˜W0,˜B)and the higgsinos(˜H±;˜H01,˜H02).These interaction eigenstates mix non-trivially via their mass matrices:the two charged mass eigenstates,called charginos, are denoted by˜χ±i(i=1,2),and the four neutral mass eigenstates,called neutralinos, by˜χ0k(k=1,2,3,4).All masses and couplings in the chargino-neutralino sector can be described in terms of the three parameters m1/2[which determines the SU(2)×U(1) gaugino masses via eq.(14)],µ(the supersymmetric Higgs-Higgsino mass term)and tanβ.It should be noted that˜χ01,often denoted simply as˜χ,is the favourite candidate for being the LSP.An alternative candidate is˜ντ,but this is actually the LSP for a much smaller range of parameter space.Notice also that there is no particular reason to assume that˜χis a pure photino,as is often done in phenomenological analyses.In summary,the particle spectrum of the MSSM can be approximately described in terms offive basic parameters:•The mass m A of the CP-odd neutral Higgs boson(or any other SUSY Higgs mass)•The ratio of VEVs tanβ≡v2/v1•The universal gaugino mass m1/2,or equivalently the gluino mass m˜g •The universal scalar mass m0•The supersymmetric Higgs-Higgsino massµOf course,the top-quark mass is undetermined,as in the SM.Also,as we shall see later,more subtleties have to be introduced for the description of the stop system. 2.2.Searches for SUSY Higgs bosonsWe have already mentioned the fact that,at the classical level,the Higgs sector of the MSSM is very tightly constrained.However,as extensively discussed at this workshop9,26,27,Higgs boson masses and couplings are subject to large,finite radia-tive corrections,dominated by loops involving the top quark and its supersymmetric partners.To illustrate the case with a simple example,we can assume a universal soft SUSY-breaking squark mass,m˜q,and negligible mixing in the stop mass matrix.The leading correction to the neutral CP-even mass matrix is then∆M2R 22=3m2W sin2βlog 1+m2˜qFig.3.In the(m h,H,m A)plane,and for the parameter choice m t=140GeV,m˜q=1TeV: the domain presently excluded,shown cross-hatched,and the domain which can be explored at LEP II,shown hatched.The dash-dotted line is the kinematic limit for HA associate production at500GeV(from Ref.31).same assumptions as for Eq.(15)and choose the numerical values m t=140GeV,m˜q= 1TeV:for this parameter choice,the maximum value of m h,reached for m A≫m Z and tanβ≫1,is approximately110GeV,O(20GeV)larger than the tree-level upper bound.For given m A and tanβ,the shift in m h can be as large as O(50GeV),when tanβ∼1.In particular,after radiative corrections one can have not only m h>m Z, but also m h>m A.As discussed by Clare28and Fisher29,the relevant processes for MSSM Higgs boson searches at LEP I are Z→hZ∗and Z→hA,which play a complementary role,since their rates are proportional to sin2(β−α)and cos2(β−α),respectively. An important effect of radiative corrections is to render possible,for some values of the parameters,the decay h→AA,which would be kinematically forbidden according to tree-level formulae.Experimental limits that take radiative corrections into account have by now been obtained by the four LEP collaborations,using different methods to present and analyse the data,and different ranges of parameters in the evaluation of radiative corrections.An example is given in Fig.3,where the cross-hatched area corresponds to the presently excluded region for the parameter choice m t=140GeV, m˜q=1TeV.The situation in which the impact of radiative corrections is most dramatic is the search for MSSM Higgs bosons at LEP II,as discussed at this workshop by Katsanevas30.At the time when only tree-level formulae were available,there was hope that LEP could completely test the MSSM Higgs sector.According to tree-level for-mulae,in fact,there should always be a CP-even Higgs boson with mass smaller than m Z(h)or very close to it(H),and significantly coupled to the Z boson.However,thisresult can be completely upset by radiative corrections.A detailed evaluation of the LEP II discovery potential can be made only if crucial theoretical parameters(such as the top-quark mass and the various soft supersymmetry-breaking masses)and experi-mental parameters(such as the centre-of-mass energy,the luminosity,and the b-tagging√efficiency)are specified.Taking for examples. Associated HA production is typically negligible at these energies.The hatched area of Fig.3shows the domain accessible to LEP II for the mentioned parameter choice,for an integrated luminosity of500pb−1and for a detector similar to the ALEPH detector at LEP:one can see that the theoretically allowed parameter space cannot be fully tested.Of course,one should keep in mind that there is,at least in principle,thepossibility of further extending the maximum LEP energy up to values as high as √s∼500GeV and a luminosity of order 1033cm−2sec−1:a detailed study of the discovery potential of such a collider has been presented at this workshop by Grivaz31.Among the relevant production mechanisms there are those already mentioned for LEP II:(a)e+e−→hZ,(b)e+e−→HZ, (c)e+e−→hA,(d)e+e−→HA;in addition,one can consider W W and ZZ fusion: (e)e+e−→hννor He+e−.Considering the domain that will remain unexplored if the centre-of-mass energy at LEP II is limited to190GeV, there are four main configurations(see Fig.3):in(1)h is SM-like and accessible via(a) and(e);in(2)one has in addition the possibility of detecting(d);in(3)the observable processes are(b),(c)and(f);in(4)all processes are kinematically allowed and only moderately suppressed with respect to the SM case.Also,in regions(2),(3)and(4)one can observe pair production of charged Higgses:(g)e+e−→H+H−.In summary,such a linear e+e−collider would allow for a complete exploration of the MSSM parameter space:if the MSSM is indeed correct,one could expect the guaranteed detection of at least one neutral Higgs state and the concrete possibility of a detailed spectroscopy of the Higgs sector.Another interesting possibility offered by a linear e+e−collider is the study ofγγcollisions at very high energy and luminosity,thanks to a back-scattered laser beam facility.The physics impact of such a machine on the SUSY-Higgs sector has been dis-cussed by Gunion32at this meeting,who emphasized its complementarity with respect to the e+e−mode.The next question,which was discussed by Kunszt33and also by Gunion32,is whether the LHC/SSC can explore the full parameter space of the MSSM Higgs bosons.。

写一篇地磅维护的英语作文Truck Scale Maintenance: A Comprehensive Guide.Truck scales, also known as weighbridges, are essential tools for weighing commercial vehicles and their cargo. Accurate and reliable truck scale maintenance is crucial to ensure the continued precision and longevity of these critical weighing systems. This guide provides a comprehensive overview of truck scale maintenance, covering key procedures, best practices, and troubleshooting tips.Routine Maintenance.Regular maintenance is essential to keep truck scales functioning optimally. The frequency of routine maintenance may vary depending on the usage and environmental conditions, but the following tasks should typically be performed monthly or quarterly:1. Cleaning:Remove debris, dirt, and moisture from the load cells, load cell cables, and scale platform.Use a soft brush, compressed air, or a mild cleaning solution (avoid harsh chemicals).2. Inspection:Visually inspect all components for damage, corrosion, or loose connections.Check the load cells for proper alignment and the platform for levelness.Examine the scale indicator for proper functionality and display accuracy.3. Lubrication:Lubricate all moving parts, such as bearings, pivot points, and lever arms.Use a designated lubricant compatible with the specific scale components.4. Calibration:Calibration ensures the scale's accuracy by adjustingit to match a known weight standard.Use certified calibration weights and follow the manufacturer's calibration procedures.Troubleshooting.Despite proper maintenance, issues may arise with truck scales. Common troubleshooting steps include:1. Scale Inaccuracy:Check for uneven loading, debris on the scale platform, or misalignment of load cells.Re-calibrate the scale if necessary.2. Load Cell Failure:Identify the faulty load cell by performing a load test or using a diagnostic tool.Replace the damaged load cell with a new one of the same capacity.3. Display Problems:Check the connections between the indicator and the load cells.Troubleshoot the indicator itself by testing its functionality with a known weight.4. Platform Damage:Inspect the platform for cracks, corrosion, or deformation.Repair or replace damaged platform sections as needed.Best Practices.To enhance the longevity and accuracy of truck scales, follow these best practices:Use the scale within its rated capacity.Avoid overloading or uneven loading.Train operators on proper weighing techniques.Keep the scale area clean and dry.Protect the scale from extreme temperatures and humidity.Conclusion.Truck scale maintenance is critical for ensuringaccurate weighing and maintaining compliance. By performing regular routine maintenance and addressing issues promptly through troubleshooting, businesses can extend the lifespan of their truck scales and ensure their continuedreliability. It is recommended to engage certified service technicians for professional maintenance and repairs as needed. By adhering to these guidelines, businesses can optimize the performance of their truck scales, ensuring the safety, efficiency, and accuracy of their weighing operations.。

肥胖的问题英语作文Title: The Epidemic of Obesity: Causes, Consequences, and Solutions。

Obesity is a pressing global health issue that has reached epidemic proportions in recent years. It is characterized by excessive accumulation of body fat, leading to adverse health effects and increased risk of chronic diseases. In this essay, we will delve into the causes, consequences, and potential solutions to this growing problem.Firstly, let's examine the causes of obesity. One of the primary factors contributing to obesity is unhealthy dietary habits. The consumption of high-calorie, low-nutrient foods, such as fast food, sugary beverages, and processed snacks, has become increasingly prevalent in modern society. Additionally, sedentary lifestyles characterized by prolonged sitting and minimal physical activity play a significant role in the development ofobesity. With the rise of technology and automation, many individuals engage in less physical activity, opting for screen time over exercise.Moreover, socioeconomic factors can also influence the prevalence of obesity. Limited access to affordable,healthy food options in certain communities, known as food deserts, can contribute to poor dietary choices and obesity. Furthermore, socioeconomic status often correlates with educational attainment and access to healthcare, which can impact an individual's ability to make informed decisions about their health and seek medical assistance when needed.The consequences of obesity are far-reaching and profound, affecting both individuals and society as a whole. From a health perspective, obesity increases the risk of developing various chronic conditions, including type 2 diabetes, cardiovascular disease, hypertension, and certain types of cancer. Furthermore, obesity can have detrimental effects on mental health, leading to depression, low self-esteem, and body image issues.On a societal level, the economic burden of obesity is substantial. Healthcare costs associated with treating obesity-related conditions place a significant strain on healthcare systems worldwide. Additionally, obesity can negatively impact productivity and quality of life, leading to absenteeism, disability, and decreased life expectancy.Despite the challenges posed by obesity, there are potential solutions that can help mitigate its prevalence and impact. One approach is to promote healthy eating habits and physical activity from an early age through education and public health campaigns. Schools can play a crucial role in this effort by implementing nutrition education programs and providing opportunities for physical activity during the school day.Furthermore, policies aimed at creating environments that support healthy choices can make a significant difference. This includes initiatives such as implementing taxes on sugary beverages, restricting advertising of unhealthy foods to children, and subsidizing the cost of healthy foods in underserved communities.Individuals also have a role to play in combating obesity by making healthier lifestyle choices. This includes adopting a balanced diet rich in fruits, vegetables, whole grains, and lean proteins, as well as engaging in regular physical activity. Small changes, such as taking the stairs instead of the elevator or opting for water instead of sugary drinks, can add up to significant improvements in overall health.In conclusion, obesity is a complex and multifaceted issue with far-reaching implications for individuals, communities, and society as a whole. By addressing the root causes of obesity and implementing strategies to promote healthy behaviors, we can work towards creating a healthier future for generations to come. It is imperative that we take action at all levels – individual, societal, and governmental – to combat this epidemic and improve the well-being of our global population.。

HEAVY ENCLOSED CONDUCTOR SYSTEMS2VAHLE DUCTING SYSTEMS 1912Basic DescriptionThe totally enclosed VAH LE-Conductor Rail Trun-king Systems have been manufactured since 1925 and have proven an outstanding success for safe power feeding of dockside cranes, loading-brid-ges, container handling equipment etc. in all major ports and other material handling places.The ducting system is used in any position where overhead or bare conductors could create difficul-ties in regard to space available or where safety is of utmost importance.The ducting can be either below or above ground level and when necessary it can be installed in cur-ves. The flush-mounted version is normally instal-led in a concrete trench of standard dimensions as illustrated, while in the surface-mounted version the trunking is made of steel. Other concrete trench dimensions are possible in case of space limitation or where high-voltage systems require a larger duct. All versions are entirely covered by steel-plates resting on both sides of the ducting, one side being hinged.The plates facilitate walking and the system can be used as a catwalk where railway-lines, sleepers etc. impede normal walking. H eavy wheel loads can be taken and cover plates up to one inch thickness or chequered cover plates with under-welded reinforcements are quite common. The individual plates cannot be lifted by hand, but can be opened with simple tools to enable inspection or maintenance of the conductor rails, insulators and current collectors.A practically unlimited number of cranes or other machinery can be supplied by this VAHLE-System and cranes can be added provided that the con-ductor rails are of the proper capacity. The ducting system can be extended on either side with mini-mum interruption of normal operation. Interconnect-ing switches to feed various berths separately or to arrange for hospital bays are ready available.The simple design of the VAH LE ducting systems provides maximum reliability under heavy duty ser-vice.The system meets the usual safety regulations.Cover Plate lifting devicesThere are two basic systems, the one used in connection with VAH LE ducting type ”A“ - lifting arm rigidly mounted to the crane-undercarriage and the other system being used in connection with VAHLE ducting type ”B“ and ”C“ - lifting bogie with four track wheels and articulated attachment to the crane-undercarriage.Type ”A’’ of the VAH LE ducting system is mainly for lighter duty short runs with no misalignment between crane rail and the duct edge. The cover plate lifting bogies of VAH LE ducting ”B“ and ”C“are rolling on the steel angle, channel or Z-beam protecting the upper edges of the concrete trench.The articulated towing linkage can compensate for dips or lateral misalignment of up to 150 mm.Both systems have bronze gliders and lid lifting rol-lers with plastic coating to ensure smooth raising and lowering of the cover plates, even with high travelling speeds.Spring loaded, sealed VAH LE current collectors with high-quality metal impregnated carbon shoes are attached to the lifting devices and guarantee a continuous contact with either lateral or upright mounted conductor rails. The type of current collectors will be selected in accordance with the required ampere load.Trench toleranceTRENCH MOUNTED31912*The cover plate dimensions and permissible wheel loads apply to 500 mm (20’’) width of trench.Standard hinges (surface mounted) are also available.y ±15x ±100y ±50x ±100y ±504VAHLE DUCTING1912These heavy duty enclosed conductor systems mainly serve for safe mobile power feeding of dockside cranes, loading and unloading facilities, container handling equipment, transfer brid-ges and many other applications of similar nature. The conduc-tor trench system is installed in parallel to the machinery track.The main features are: The trench cover consists of steel plates with a link connection to each other so to form a continuous steel ribbon. The cover plate lifting bogies connected to the crane undercarriage via an articulated towing arm will lift the rib-bon caterpillar-like when riding along the ducting system. The lifting bogies allow for free passing of the conductor cable towards the crane.The connection of the cover plate lifting bogies and the crane undercarriage does compensate for dips or lateral misalignment by this not interfering a safe and continuous pick-up action of the current collectors. The wheel assemblies of the lifting bogies are well-spaced in order to avoid pinching or jamming.The thickness of the cover plates will be designed in accordan-ce to the possible wheel loads of crossing traffic over the con-ductor trench. The system can be installed in bends.The VAH LE conductor trench is easy accessible for inspectionand maintenance by just dismantling one linkage between twoplate sections – all other plates can then be removed by lifting them a little over 30°. The same easy way applies for re-installing.VAHLE Conductor trench system EID for container handling crane.VAHLE DUCTING51912x ±100y ±50x ±100y ±50x ±100y ±506SURFACE MOUNTED1912Basic DescriptionThe VAHLE-Surface Mounted Ducting System is used in subsi-dence and filled-up areas not allowing for a concrete trench.The conductor housing is fixed to concrete or timber sleepers and is placed parallel to the crane rail.The four conductors (3 -phases + ground) are arranged laterally on both sides or upright-mounted on the bottom of the housing.The current is collected by spring-loaded collectors which are bolted to a moving cover plate lifting bogie. This lifting trolley with its four track wheels runs on the hinge U-channel and an edge angle iron and is connected to the crane undercarriage by means of an articulated joint capable to compensate for hori-zontal and vertical misalignment up to 150 mm between crane rail and conductor system.Engineering Data:Standard steel ducting:6 m sections - 4 mm sheetsframe- and support-centers: 2 m.Hinged cover plates of chequered 6 mm sheets.Conductors:VAHLE Copperhead Rails F 45, K 45, AC 45 or C 45available from 500 to 1500 amps (see catalog No. 1a).Standard insulators VDB,max. 1000 Volts, 2 m centers.Cover Plate lifting Bogie with Current Collectorsavailable from 100 to 800 amps.VAHLE FK-SYSTEM71912Basic DescriptionThe H eavy Duty Steel Enclosed Conductor System, Type FK represents an unique arrangement of VAHLE-Copperhead Rails.It is mainly used for the safe long travel electrification of heavy O.H.T. Cranes, Portal Cranes, Container Handling facilities and other installations with movable machinery.The conductors are supported by double block insulators which are inserted in the frame profiles of FK housing.The standard housing accomodates 4 conductors (3 phases +ground), 2 top and 2 bottom rails.More conductors can be installed with only a slight increase in the width of the system.The FK is a real space-saving unit because the collector trolley (available for 120, 240, 360 amps.) does not require an extra runway. It is carried on insulated plastic rollers and guided on the copperheads of VAHLE-Conductors.The front slot opening for the pick-up cable is covered by a neoprene sealing strip which makes the system proof against rain, snow and dust. The towing arrangement compensates for misalignment.Engineering DataEnclosure:Conductors:Housing with frame work410 Amp.4 x F 35/50of 3 mm steel sheets - 7 m long 530 Amp.3 x F 35/100Detachable front covers *1 x F 35/50of 2,5 mm steel sheets, 3,5 m long 730 Amp.3 x F 35/200Neoprene sealing strip 4 x 100 mm 1 x F 35/100Support centers: 3,5 m max. 600 VoltsCurrent collector trolleys:Insulator centers: FKW 120 A, FKW 240 A, 1,75 m FKW 360 A*hinged front covers if required.VAHLE FK-system for container terminal8VAHLE CP SYSTEM1912Basic DescriptionThe VAHLE CP-Crashproof Conductor Line is a combination ofa guide rail and a safety electrification system. The surface mounted housing serves as border of the quay and is placed adjacent to the seaside crane rail. The U-shaped housing is manufactured with a thickness of 6, 8, 10 or 12 mm and con-tains 3 laterally mounted phase conductors. The current collec-tor trolley is running on a continuous flat iron profile on the bot-tom and is well guided against the top mounted earth conduc-tor (welded to the housing). The front covers have a thickness of 3 mm, and the slot opening for the pick-up cable is covered bya neoprene strip. Accordingly this system is proof against rain,snow and dust and an accidental contact with conductors is impossible.The standard housing can accomodate conductor rails with a continuous current capacity up to 535 amps. Besides the stan-dard system we supply a larger housing – see dimensions in brackets – capable to take conductor rails up to 900 amps.Systems to clients specification, also with multiple control con-ductors, are available.Engineering DataEnclosure:Conductors:330 Amp. 3 x L 20/50Housing of 6, 8, 10 or 12 mm 1 x F 35/50steel sheets 6 m long450 Amp. 3 x L 20/100Detachable front covers1 x F 35/50of 3 mm steel sheets,2 m long 535 Amp.3 x C 20/200Neoprene sealing strip 4 x 100 mm 1 x F 35/100Support centers: max. 6 m max. 600 VCurrent collector trolleys:Insulator centers: 1 mCPW 120 A, CPW 240 A,CPW 360 A9Customer:Attention of:Address:Questions regarding Conductors:1. Type of crane/equipment to be electrified:2. Length of track:max. travelling speed: m/min.3. Number of cranes/equipment to be electrified by the one system:4. Ampere load of each crane/equipment:5. Voltage:Volt:~/=:Phases:c/s:6. Number of conductors required:Power lines:Control lines:Neutral (ground):7. Number and position of feeder points:8. Sectionalization and separate feeding of conductor system (provide prints and sketches):9. Type of conductors preferably wanted:Copperhead/solid copper conductor rails:Insulated unipole conductor rails:Multipole protected conductors:Motor Data Hoist motor Auxiliary hoistTravel motor-main-trolley Travel motor-aux.-trolley Main Travel Slewing LuffingCrane 1Crane 2Crane 3Power kW/PS Power kW/PSPower kW/PSCurrent AmpsCurrent AmpsCurrent AmpsDuty factor %Duty factor %Duty factor %Please copy and fill-in this questionnaire.10Questions regarding conductor trench:1. Type:Below floor level:Surface mounted:2. Indoor:Outdoor:3. Special site conditions (Humidity, dust, chemical influence, subsidence):4. Max. load on trench cover plates:Pedestrians:Type of vehicles:Wheel load and dimension of wheels:5. Curved run, radius (submit print or sketch):6. Special safety requirements to be observed (mining, chemical industry, etc.):Additional Information:230774704Please copy and fill-in this questionnaire.To our nearest local VAHLE-agency:TYPICAL INSTALLATIONS 111912In accordance with our company’s policy of continued improvement, we reserve the right to amend specifications and details at any time.Steel enclosed conductor system for RTS maintenance shopVAHLE-EID conductor trench for container terminalCatalog No. 5/E 20000011 · P r i n t e d i n G e r m a n y · 2000-3059 · 1000 · 11/00PAUL VAHLE GMBH & CO. KG · D 59172 KAMEN/GERMANY · TEL. 02307/7040Internet: www.vahle.de · e-mail: postmaster @vahle.de · FAX 02307/74704Catalog No.Copperhead Conductor Systems 1aBattery Charging Systems 1bInsulated Conductor Systems U 102aInsulated Conductor Systems U 20 – U 30 – U 402bInsulated Conductor Systems U 15 – U 25 – U 352cAluminium Enclosed Conductor Systems LSV – LSVG 3aSteel Enclosed Conductor Systems SLG – HSL 3bPowerail Enclosed Conductor Systems KBSL – KSL – KSLT – KSG 4aPowerail Enclosed Conductor Systems VKS – VKL 4bPowerail Enclosed Conductor System MKLD – MKLF – MKLS 4cHeavy Enclosed Conductor Systems 5Trolley Wire and Accessories 6Cable Tenders 7Cable Carriers for -tracks 8aCable Carriers for Flatform Cable on -beams 8bFCable Carriers for Round Cable on -beams 8bRCable Carriers for -tracks 8cConductor Cables and Fittings 8LSpring Operated Cable Reels 9aOverload Protection Systems 9bV AHLE POWERCOM ®– Data Transmission Systems 9cCPS – Contactless Power Supply 9dSMG – Slotted Microwave Guide 9eMotor Powered Cable Reels10Reg.No.3140。