EUROPEAN ORGANIZATION FOR NUCLEAR RESEARCH
CERN - PS DIVISION
CERN/PS 2001-055 (RF)
NUFACT NOTE 089
STATUS OF EUROPEAN STUDIES FOR A NEUTRINO FACTORY
AT CERN
R. Garoby (for the Neutrino Factory Working Group)
Abstract
Studies for a Neutrino Factory at CERN have made remarkable progress during the last year, supported by specialists from numerous laboratories in Europe and in close connection with teams looking at similar projects in the USA and in Japan. Although many options are still open, a reference scheme is pursued and work has advanced on many on its components. The status of these studies is described, as well as the future plans. Potential evolutions of the reference scheme and the possibility of a staged realisation are also commented upon.
NuFACT'01 Workshop, May 24-30, 2001, Tsukuba Japan
Geneva, Switzerland
23 August 2001
Status of European Studies for a Neutrino
Factory at CERN
R.Garoby,for the Neutrino Factory Working Group
CERN,Geneva,CH-1211Geneva23,Switzerland
Abstract
Studies for a Neutrino Factory at CERN[1,2,3]have made remarkable progress during the last year,supported by specialists from numerous laboratories in Europe and in close connection with teams looking at similar projects in the USA and in Japan.Although many options are still open,a reference scheme is pursued and work has advanced on many on its components.The status of these studies is described, as well as the future plans.Potential evolutions of the reference scheme and the possibility of a staged realisation are also commented upon.
1CERN Reference Scheme
The neutrinos delivered by a Neutrino Factory result from the decay of high energy muons circulating in a storage ring.These muons are themselves decay products of the pions produced by the interaction of a proton beam with the atoms of a target.
In the CERN scheme(see Fig.1),the H?beam supplied,at75Hz,by a 2.2GeV Superconducting Linac(SPL),is injected during2.2ms in an accu-mulator ring whose proton bunches are afterwards shortened in a compres-sor ring.A mean?ux of1.11016protons/s(or～1023protons/year,taking 107s/year)is delivered to the target,with the characteristics listed in Table 1.
A liquid metal jet is being used for the target,inserted inside a magnetic horn for collecting pions over a broad range of kinetic energy(100to300MeV) and a large solid angle.These pions as well as the muons resulting from their decays are transported in a30m long decay channel with transverse focus-ing by a1.8T solenoidal?eld.After passing through this channel,the muon bunches traverse a series of44MHz cavities which by”rotation”in the lon-gitudinal phase plane,reduce their energy spread by a factor of2.The beam Preprint submitted to Elsevier Science23August2001
https://www.doczj.com/doc/242123312.html,yout of the CERN reference scheme for a Neutrino Factory Parameter Value Unit
Mean Beam Power4MW
Kinetic energy 2.2GeV
Repetition rate75Hz
Pulse duration 3.3μs
Number of bunches140
Pulse intensity1.511014p/pulse
Bunch spacing22.7ns
(Bunch frequency)(44)(MHz)
Bunch length(σ)1ns
Relative momentum spread(σ)510?3
Norm.horizontal emittance(σ)50μm.rad
Table1
Proton beam on target
then passes through liquid hydrogen cells for ionisation cooling,and44and 88MHz RF structures for recovery of longitudinal energy.After this treat-ment,250m behind the target,each transverse emittance has been divided by four(conversely,the density in each transverse phase plane is multiplied by4).Solenoidal focusing is still used in the following linear accelerator which operates at harmonics of44MHz to increase the energy up to2GeV.
A cascade of2Recirculating Linear Accelerators(RLA),equipped with LEP-type352MHz superconducting RF cavities providing a total of12GeV of single-pass energy gain,accelerate this beam in4turns up to50GeV.
2
The3.3μs burst of50GeV muons is injected into the2km circumference muon storage ring,where it is left to decay until the next burst is available, 13.3ms later.More than1014μ/s enter this ring,and approximately31020 neutrinos are then generated every year in each of the long straight sections oriented towards remote experiments,thousands of kilometres away.
2Proton Driver
2.1Reference Design
The present design makes extensive use of the large inventory of RF equip-ment dismantled from LEP.The800m long superconducting Linac[4]that accelerates the H?ions to2.2GeV re-uses all klystrons and60%of the LEP modules in its high-energy part(see Fig.2).Newβ=0.52andβ=0.7accel-eration modules are assumed between120and390MeV.Between390MeV and1GeV,LEP cryostats are re-used,equipped with new5cells,β=0.8 cavities.Above1GeV,LEP modules are used without modi?cation.Below
0.52 0.7 0.8
RFQ1 chop. RFQ2
Superconducting section
https://www.doczj.com/doc/242123312.html,yout of the CERN reference scheme for a Neutrino Factory
120MeV,room temperature accelerating structures are employed.Leaving the ion source at45keV,the H?beam is bunched at352MHz and acceler-ated to3MeV in an RFQ.It then passes through a transfer line equipped with fast de?ecting electrostatic kickers(”choppers”)which eliminate the un-wanted bunches onto a collector and provide the proper time structure for an optimum longitudinal capture in the accumulator.Further acceleration to 120MeV is made cascading an RFQ,a Drit Tube Linac(DTL)and a Cavity Coupled Drift Tube Linac(CCDTL).
2.2GeV protons are accumulated over660turns in the accumulator ring, using charge exchange injection[5].140of the146buckets generated by the 44MHz RF system are progressively populated by up to1.081012p/b.At
3
the end of accumulation,the bunches are fast ejected and transferred into the compressor ring,where bunch compression takes place in7turns,with2MV at44MHz and350kV at88MHz.The1ns rms long bunches are then ejected onto the target.
On the CERN site(see Fig.3),the accumulator and the compressor rings are situated at the location of the ex-ISR,and existing tunnels are re-used for the transfer of the SPL beam to the PS and to the ISOLDE experimental
facility.
2.2Ongoing Activities and Design Trends
Theoretical work is concentrated on the re?nement of the SPL design and the solution of the remaining problems,in close relation with the development of critical hardware(Table2).In particular,a recent study has underlined that more work is required for a proper control of the?eld in the cavities when multiple superconducting resonators are driven by a single klystron[6]. Improvements to the reference design[4]are being studied,based on reducing the repetition rate to50Hz,generalising the use ofβ=0.8cavities up to 2.2GeV and increasing the beam current during the pulse.Preliminary inves-tigations of the consequences for the accumulator and compressor rings have not revealed any dramatic problem,apart from more stringent impedance re-quirements because of the microwave instability and the need for more e?cient countermeasures against electron clouds and their e?ect.
Alternatively,if the production of pions from a2.2GeV proton beam proves to be unfavourable,or if di?culties arise in the neutrino complex,due to the
4
Item Main Issue
H?Source Design
Chopper System design
RT Linac Structures development
SC cavities Pulsed test of cavities
Dev.of lowβstructures
Klystrons&supplies pulsed operation
Servo-systems Field stab.in pulsed mode
Beam dynamics Optimisation
Table2
Studies for the proton driver
choice of23ns spaced bunches,the design of the proton driver could change and make use of Rapid Cycling Synchrotron(s)(RCS)[7].
2.3Other Applications and Staged Approach
Apart from its main use as a driver for a future Neutrino Factory,the2.2GeV proton source could bene?t the rest of the accelerator complex at CERN, replacing the present Linac2/PSB set-up and providing improved beam characteristics at the entrance of the PS.The present ISOLDE facility could easily be supplied with5times more beam current than at present,while removing constraints from the busy PS supercycle.Moreover,a second gener-ation ISOLDE facility could be accommodated which would fully pro?t from the SPL beam[8].Potential bene?ts for the approved high energy physics experiments are also under study[9].
Recent investigations have underlined the interest for physics of a staged ap-proach where only the proton driver would be needed to generate a conven-tional neutrino beam aimed at a medium distance experiment(～100km)[10]. 3Target and Capture
3.1Reference Design
The target and pion capture systems?t tightly together and represent one of the most di?cult engineering challenges in the design of a Neutrino Factory,
5
for which no solution has yet been tested enough to be considered as viable.In the case of the CERN reference scheme,preference is given to a liquid metal target[11,12]and horn focusing[13,14],although solenoid focusing is not discarded.
For convenience,mercury(Hg)is being used for the preliminary tests.Exper-iments with beam have begun at BNL,sending24GeV protons onto Hg in a trough,to be followed by similar tests with1.4GeV protons in the ISOLDE target area[12].Some results have also been obtained by the American col-laboration concerning the e?ect of the proton beam onto an Hg jet[15].Until now,these tests at1/100of the ultimate power density and1/10of the fore-seen jet speed have shown the expected radial”explosion”during the impact, but no upstream propagation along the jet.
The horn design is demanding because of the≥50Hz cycling rate which accelerates mechanical fatigue and causes high thermal dissipation,especially in the waist region of the central conductor where the target will be located. A300kA,1m long prototype has been designed[16](Figure4)as well as its power supply[17].They are under construction and will be tested within a year.In the full implementation,a600kA outer horn is foreseen,surrounding the300kA one,for focusing higher energy larger angle pions.For studying the penetration of the Hg jet on axis inside a high?eld solenoid,a safety accepted experimental set-up is now available.First tests with a13T magnet at Grenoble have not revealed any problem.20T tests are planned in the near future.
Fig.4.Prototype horn
3.2Potential Design Evolutions
The HARP experiment[18]will take data in2001and measure precisely the production of pions with2to16GeV protons on di?erent types of targets.
6
Results will strongly in?uence the target design and possibly also the charac-
teristics of the proton driver.
The problems associated with a liquid metal target are still largely unresolved
and alternative solutions are being pursued in di?erent laboratories[19].A
new proposal was recently made at CERN of a stationary target with metal
spheres[20].A spent beam absorber is also needed to dump the3MW of
beam power that remain after the target.No satisfactory solution has yet
been proposed for its design.
4Bunch Rotation and Cooling
4.1Reference Design
The preferred solution is adapted to the small bunch spacing(namely23ns)
that can be obtained from a low-energy proton driver[21],[22].Moreover,
the time structure of the primary proton beam is preserved in this solution
and no rebunching of the muons is required before acceleration.The essential parameters of the bunch rotation and cooling channel are summarised in Table
3.After a decay path of30m,the muon bunches are rotated to reduce their
energy spread by a factor of two.Two steps of ionisation cooling are then applied,the?rst one at the mean energy of200MeV,with24cm long liquid hydrogen absorber cells and44MHz RF,and the second one at300MeV with
40cm absorber cells and88MHz RF.The low RF frequency,the need for a
high solenoid?eld on axis and the huge bore aperture resulting from the large
beam emittance contribute to make the equipment voluminous.The design is modular,as illustrated in the sketch of the44MHz part shown in Figure5. Acceleration to2GeV is obtained in a450m long linac using88and176MHz
RF accelerating structures.
Decay Rotation Cooling1Accel.1Cooling2Accel.2
Length(m)30304632112～450 Diameter(cm)606060603020
B-?eld(T) 1.8 1.8 2.0 2.0 2.6 2.6 Frequency(MHz)4444448888&176 Cavities gradient(MV/m)22244-10
Kinetic energy(Mev)2002002803002000 Table3
Parameters of the bunch rotation,cooling and pre-acceleration sections
7
1
4
c
m
2
4
c
m
Fig.5.Cooling channel modules,with44MHz cavities and superconducting solenoid Figure6illustrates the computed evolution of transverse emittance along this channel,and its?nal reduction by a factor of four.The percentage of muons surviving per incident pion is shown in Figure7.According to the particle production predicted by FLUKA(0.2π+/proton at2.2GeV),the overall yield of the system is0.
42%π+/proton.GeV in the acceptance of the?rst RLA,corresponding to1021π+/year.
r
m
s
n
o
r
m
a
l
i
s
e
d
(
m
m
.
r
a
d
)
Distance from target (m)
Fig.6.Evolution of transverse emittance
4.2Ongoing activities and design trends
Beam dynamics is concentrated on the optimisation of the channel architecture to try to increase the?ux of muons delivered inside the acceptance of the?rst RLA.A test system at88MHz to investigate high gradient operation is being prepared with equipment recuperated from the PS after the end of LEP.First results are expected at the end of2001.Tests in the presence of a high?eld solenoid will follow in2002,when the superconducting solenoids presently under design will be available.
8
p r o d u c t i o d e c a r o t a t i o c o o l i n 40M H a c c e l e r a t i o c o o l i n 80M H a c c e l e r a t i o Fig.7.Percentage of muon/incident pion
Moreover,a muon cooling test facility is considered as a necessity in order to demonstrate full-scale engineering solutions and single-particle cooling without ambiguity [23].In the present context of limited resources,such a facility will be proposed as a joint international e?ort,built and exploited by all study teams world-wide.
5Muon acceleration
5.1Reference design
Two racetrack-shaped recirculating linear accelerators accelerate the muon beams from 2to 10GeV (RLA1)and from 10to 50GeV (RLA2)respectively.Both RLAs are isochronous,and the muon bunches are accelerated on the crest of the RF wave.The main parameters are summarised in Table 4[24].This part of a Neutrino Factory complex has been identi?ed as one of the most costly [25]and will consequently require detailed engineering optimisation in due time.The 352MHz LEP-type RF cavities are installed in all straight sections.Spreaders at the end of each linac section,separate the beam into 4di?erent,vertically-stacked arcs.After the 180?bend,combiners merge the four beam energies into the input of the next linac section.5.2Ongoing activities and design trends
A satisfactory optical arrangement is still being sought for the spreaders and combiners.For the RF,a single cell 200MHz superconducting cavity is be-ing built at CERN for Cornell University,using the ”Niobium sputtered on
9
Parameter RLA1RLA2
Injection energy(GeV)210
Extraction energy(GeV)1050
Number of turns44
Linac length(m)6803813
RF frequency(MHz)352352
Mean arc radius(m)20100
Circumference(m)8064442
Gradient cavities(MV/m)7.47.4
Normalized admittance(mm rad)16.518.8
Table4
Parameters of the RLAs
Copper”technology developed for LEP[26](Figure8).By using such low-frequency cavities in RLA1and possibly also in the high-energy part of the preceding linac,acceptance in all planes would be increased.Furthermore, the length of the accelerators will be reduced if the gradient can be made
MV/m).
substantially higher than in the existing LEP cavities(7.4
6Muon Storage
6.1Reference design
A muon storage ring with a symmetrical bow-tie shape and long straight sec-tions aiming at remote neutrino experiments is proposed[27].Such a shape
10
is interesting for its advantages in terms of site layout and ?exibility of ori-entation.The machine parameters are listed in Table 5,and its geometry is sketched in Figure 9.
Parameter
Value Beam energy (GeV)50Muon ?uence (s ?1)
1014Distance to far experiments (km)
1000&3000
Normalised divergence (γ×physical rms divergence)0.1Vertical slopes (mrad)-78.6&-237.9
Circumference (m)
2007.9%of useful muon decays per circulating muon per detector (%)28.7RF frequency (MHz)352Peak RF voltage (MV)
120Mormalised emittance (mm rad) 1.67
Table 5
Parameters of muon storage ring
x horizontal coordinate (m)
y h o r i z o n t a l c o o r d i n a t e (m )
V e r t i c a l c o o r d i n a t e (m )
Position on the circumference (m)
-400
-2000.0200400
700
500
300
100
-100010002000
50
-50
-100
-150
Fig.9.Percentage of muon/incident pion
One third of the stored muons will decay in the straight sections,so that a total of ～31020neutrinos will be sent every year to each remote experiment.The
11
Gran Sasso laboratory will be one of them,and the location of the other one,～3000km away,is the subject of an ongoing debate.Although challenging,the alignment accuracy of10?5rad required for the straight sections is considered feasible.
6.2Ongoing activities and design trends
Engineering developments are needed to help optimise the performance and cost of the storage ring,but no activity has started yet.Beam dynamics studies continue.
7Conclusion
In the CERN context,where resources are diminishing and the LHC project has top priority,it is quite encouraging to report how much has been done since the study for a Neutrino Factory began,some3years ago.In that respect, the recent interest of physicists for a staged approach,where?rst generation experiments would only use the proton driver part of the Neutrino Factory complex,is highly welcome.Test set-ups are already,or will soon be,available whose results will help improve the quality of the present design and give con?dence in the feasibility of the hardware components.An important goal in the near future is to elaborate an international proposal for a muon cooling test facility to be built and exploited by a world-wide collaboration of study teams.
References
[1] B.Autin,A.Blondel,J.Ellis(editors),”Prospective Study of Muon
Storage Rings at CERN”,CERN-1999-02
[2] B.Autin et al.,”The CERN Neutrino Factory Working Group:Status
Report and Work Plan”,CERN-NuFact Note28.
[3]H.Haseroth for the CERN Neutrino Factory Working Group,”CERN
Ideas and Plans for a Neutrino Factory”,CERN-NuFact Note45. [4]M.Vretenar(editor),”Conceptual Design of the SPL,a High Power
Superconducting Proton Linac at CERN”,CERN-2000-012
[5] B.Autin et al.,”Design of a2.2GeV Accumulator and Compressor for
a Neutrino Factory”,CERN-PS/2000-011(AE),June15,2000
[6]J.Tuckmantel,”Control Instabilities in a Pulsed Multi-Cavity RF Sys-
tem with Vector Sum Feedback”,CERN-NuFact Note82
12
[7]H.Schonauer et al.,”Proton Drivers for a Neutrino Factory:the CERN
Approach”,CERN-NuFact Note46
[8]J.Aysto et al.,”A Second Generation Radioactive Nuclear Beam Facility
at CERN”,CERN/PS2000-075(OP)
[9]R.Cappi(editor),”Increasing the Proton Intensity of PS and SPS”,
CERN/PS2001-041
[10]M.Mezzetto,”Neutrino Oscillations at the SPL SuperBeam”,CERN-
NuFact Note60
[11] C.D.Johnson,”Study of the Behaviour of a Pulsed Liquid Jet Target”,
CERN-NuFact Note27.
[12] A.Fabich,H.Ravn,Private communication.
[13] A.E.Ball et al.,”Preliminary Magnetic Horn Studies in the Collection
Scheme for a Neutrino Factory”,Proceedings of the ICFA/ECFA Work-shop on”Neutrino Factories based on Muon Storage Rings”,Lyon5-9 July1999,NIM A,Vol.451,no.1,pp.359-361.
[14] A.E.Ball,A.Blondel,S.Ghilardoni,N.Vassilopoulos,”Updated Results
of the Horn Study for the Nufact”,CERN-NuFact Note42.
[15]H.Kirk et al.,”Target Studies with BNL E951at the
AGS”,Proceedings of PAC01,June2001,Chicago.(http: //https://www.doczj.com/doc/242123312.html,/papers/T uesday/AM P oster/T P AH137.pd f) [16]J.M.Maugain,S.Rangod,F.Voelker,”Study of a Horn with Integrated
Target for a Neutrino Factory”,CERN-NuFact Note80.
[17]G.Grawer,”Investigation of the Possibility to build a400kA Pulse
Current Generator to Drive a Magnetic Horn”,CERN-NuFact Note38.
[18] F.Dydak(spokesman),”Proposal to Study Hadron Production for the
Neutrino Factory and for the Atmospheric Neutrino Flux”,CERN-SPSC/99-35
[19] B.J.King,J.R.J.Bennett, A.Blondel et al.,Proceedings of the
ICFA/ECFA Workshop on”Neutrino Factories based on Muon Storage Rings”,Lyon5-9July1999,NIM A,Vol.451,no.1,pp.335-352. [20]P.Sievers,”A Stationary Target for the CERN Neutrino Factory”,
CERN-NuFact Note65.
[21] A.Lombardi,”A40-80MHz System for Phase Rotation and Cooling”,
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[23]https://www.doczj.com/doc/242123312.html,/muons/Final-Agenda.html
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[25]N.Holtkamp,D.Finley(eds.),”A Feasibility Study of a Neutrino Source
Based on a Muon Storage Ring”,FERMILAB-PUB-00-108-E(2000)
[26] E.Chiaveri,R.Losito,Private communication
[27] E.Keil,”Design of a Bow-Tie Shaped50GeV Muon Storage Ring”,
CERN-NuFAct Note48.
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of与for的用法以及区别 for 表原因、目的 of 表从属关系 介词of的用法 （1）所有关系 this is a picture of a classroom （2）部分关系 a piece of paper a cup of tea a glass of water a bottle of milk what kind of football，American of soccer？ （3）描写关系 a man of thirty 三十岁的人 a man of shanghai 上海人 （4）承受动作 the exploitation of man by man．人对人的剥削。 （5）同位关系 It was a cold spring morning in the city of London in England． （6）关于，对于 What do you think of Chinese food？ 你觉得中国食品怎么样？ 介词 for 的用法小结 1. 表示“当作、作为”。如: I like some bread and milk for breakfast. 我喜欢把面包和牛奶作为早餐。What will we have for supper? 我们晚餐吃什么?
2. 表示理由或原因,意为“因为、由于”。如: Thank you for helping me with my English. 谢谢你帮我学习英语。 Thank you for your last letter. 谢谢你上次的来信。 Thank you for teaching us so well. 感谢你如此尽心地教我们。 3. 表示动作的对象或接受者,意为“给……”、“对…… (而言)”。如: Let me pick it up for you. 让我为你捡起来。 Watching TV too much is bad for your health. 看电视太多有害于你的健康。 4. 表示时间、距离,意为“计、达”。如: I usually do the running for an hour in the morning. 我早晨通常跑步一小时。We will stay there for two days. 我们将在那里逗留两天。 5. 表示去向、目的,意为“向、往、取、买”等。如: let’s go for a walk. 我们出去散步吧。 I came here for my schoolbag.我来这儿取书包。 I paid twenty yuan for the dictionary. 我花了20元买这本词典。 6. 表示所属关系或用途,意为“为、适于……的”。如: It’s time for school. 到上学的时间了。 Here is a letter for you. 这儿有你的一封信。 7. 表示“支持、赞成”。如: Are you for this plan or against it? 你是支持还是反对这个计划? 8. 用于一些固定搭配中。如: Who are you waiting for? 你在等谁? For example, Mr Green is a kind teacher. 比如,格林先生是一位心地善良的老师。
to与for的用法和区别 一般情况下, to后面常接对象; for后面表示原因与目的为多。 Thank you for helping me. Thanks to all of you. to sb.表示对某人有直接影响比如，食物对某人好或者不好就用to; for表示从意义、价值等间接角度来说，例如对某人而言是重要的，就用for. for和to这两个介词，意义丰富，用法复杂。这里仅就它们主要用法进行比较。 1. 表示各种“目的” 1. What do you study English for? 你为什么要学英语？ 2. She went to france for holiday. 她到法国度假去了。 3. These books are written for pupils. 这些书是为学生些的。 4. hope for the best, prepare for the worst. 作最好的打算，作最坏的准备。 2．对于 1．She has a liking for painting. 她爱好绘画。 2．She had a natural gift for teaching. 她对教学有天赋/ 3．表示赞成同情，用for不用to. 1. Are you for the idea or against it? 你是支持还是反对这个想法？ 2. He expresses sympathy for the common people.. 他表现了对普通老百姓的同情。 3. I felt deeply sorry for my friend who was very ill. 4 for表示因为，由于（常有较活译法） 1 Thank you for coming. 谢谢你来。 2. France is famous for its wines. 法国因酒而出名。 5．当事人对某事的主观看法，对于（某人），对…来说（多和形容词连用）用介词to，不用for.. He said that money was not important to him. 他说钱对他并不重要。 To her it was rather unusual. 对她来说这是相当不寻常的。 They are cruel to animals. 他们对动物很残忍。 6．for和fit, good, bad, useful, suitable 等形容词连用，表示适宜，适合。 Some training will make them fit for the job. 经过一段训练，他们会胜任这项工作的。 Exercises are good for health. 锻炼有益于健康。 Smoking and drinking are bad for health. 抽烟喝酒对健康有害。 You are not suited for the kind of work you are doing. 7. for表示不定式逻辑上的主语，可以用在主语、表语、状语、定语中。 1．It would be best for you to write to him. 2．The simple thing is for him to resign at once. 3．There was nowhere else for me to go. 4．He opened a door and stood aside for her to pass.
For的用法 1. 表示“当作、作为”。如: I like some bread and milk for breakfast. 我喜欢把面包和牛奶作为早餐。 What will we have for supper? 我们晚餐吃什么? 2. 表示理由或原因,意为“因为、由于”。如: Thank you for helping me with my English. 谢谢你帮我学习英语。 3. 表示动作的对象或接受者,意为“给……”、“对…… (而言)”。如: Let me pick it up for you. 让我为你捡起来。 Watching TV too much is bad for your health. 看电视太多有害于你的健康。 4. 表示时间、距离,意为“计、达”。如: I usually do the running for an hour in the morning. 我早晨通常跑步一小时。 We will stay there for two days. 我们将在那里逗留两天。 5. 表示去向、目的,意为“向、往、取、买”等。如: Let’s go for a walk. 我们出去散步吧。 I came here for my schoolbag.我来这儿取书包。 I paid twenty yuan for the dictionary. 我花了20元买这本词典。 6. 表示所属关系或用途,意为“为、适于……的”。如: It’s time for school. 到上学的时间了。 Here is a letter for you. 这儿有你的一封信。 7. 表示“支持、赞成”。如: Are you for this plan or against it? 你是支持还是反对这个计划? 8. 用于一些固定搭配中。如: Who are you waiting for? 你在等谁? For example, Mr Green is a kind teacher. 比如,格林先生是一位心地善良的老师。 尽管for 的用法较多，但记住常用的几个就可以了。 to的用法: 一：表示相对，针对 be strange (common, new, familiar, peculiar) to This injection will make you immune to infection. 二：表示对比，比较 1：以-ior结尾的形容词，后接介词to表示比较，如：superior ,inferior,prior,senior,junior 2: 一些本身就含有比较或比拟意思的形容词，如equal，similar，equivalent，analogous A is similar to B in many ways.
介词for用法归纳 用法1：(表目的)为了。如： They went out for a walk. 他们出去散步了。 What did you do that for? 你干吗这样做？ That’s what we’re here for. 这正是我们来的目的。 What’s she gone for this time? 她这次去干什么去了？ He was waiting for the bus. 他在等公共汽车。 【用法说明】在通常情况下，英语不用for doing sth 来表示目的。如： 他去那儿看他叔叔。 误：He went there for seeing his uncle. 正：He went there to see his uncle. 但是，若一个动名词已名词化，则可与for 连用表目的。如： He went there for swimming. 他去那儿游泳。(swimming 已名词化) 注意：若不是表目的，而是表原因、用途等，则其后可接动名词。(见下面的有关用法) 用法2：(表利益)为，为了。如： What can I do for you? 你想要我什么？ We study hard for our motherland. 我们为祖国努力学习。 Would you please carry this for me? 请你替我提这个东西好吗？ Do more exercise for the good of your health. 为了健康你要多运动。 【用法说明】(1) 有些后接双宾语的动词(如buy, choose, cook, fetch, find, get, order, prepare, sing, spare 等)，当双宾语易位时，通常用for 来引出间接宾语，表示间接宾语为受益者。如： She made her daughter a dress. / She made a dress for her daughter. 她为她女儿做了件连衣裙。 He cooked us some potatoes. / He cooked some potatoes for us. 他为我们煮了些土豆。 注意，类似下面这样的句子必须用for： He bought a new chair for the office. 他为办公室买了张新办公椅。 (2) 注意不要按汉语字面意思，在一些及物动词后误加介词for： 他们决定在电视上为他们的新产品打广告。 误：They decided to advertise for their new product on TV. 正：They decided to advertise their new product on TV. 注：advertise 可用作及物或不及物动词，但含义不同：advertise sth＝为卖出某物而打广告；advertise for sth＝为寻找某物而打广告。如：advertise for a job=登广告求职。由于受汉语“为”的影响，而此处误加了介词for。类似地，汉语中的“为人民服务”，说成英语是serve the people，而不是serve for the people，“为某人的死报仇”，说成英语是avenge sb’s death，而不是avenge for sb’s death，等等。用法3：(表用途)用于，用来。如： Knives are used for cutting things. 小刀是用来切东西的。 This knife is for cutting bread. 这把小刀是用于切面包的。 It’s a machine for slicing bread. 这是切面包的机器。 The doctor gave her some medicine for her cold. 医生给了她一些感冒药。 用法4：为得到，为拿到，为取得。如： He went home for his book. 他回家拿书。 He went to his friend for advice. 他去向朋友请教。 She often asked her parents for money. 她经常向父母要钱。
of 1....的,属于 One of the legs of the table is broken. 桌子的一条腿坏了。 Mr.Brown is a friend of mine. 布朗先生是我的朋友。 2.用...做成的;由...制成 The house is of stone. 这房子是石建的。 3.含有...的;装有...的 4....之中的;...的成员 Of all the students in this class,Tom is the best. 在这个班级中,汤姆是最优秀的。 5.(表示同位) He came to New York at the age of ten. 他在十岁时来到纽约。 6.(表示宾格关系) He gave a lecture on the use of solar energy. 他就太阳能的利用作了一场讲演。 7.(表示主格关系) We waited for the arrival of the next bus. 我们等待下一班汽车的到来。
I have the complete works of Shakespeare. 我有莎士比亚全集。 8.来自...的;出自 He was a graduate of the University of Hawaii. 他是夏威夷大学的毕业生。 9.因为 Her son died of hepatitis. 她儿子因患肝炎而死。 10.在...方面 My aunt is hard of hearing. 我姑妈耳朵有点聋。 11.【美】(时间)在...之前 12.(表示具有某种性质) It is a matter of importance. 这是一件重要的事。 For 1.为,为了 They fought for national independence. 他们为民族独立而战。 This letter is for you. 这是你的信。
1.两者都可以引出间接宾语，但要根据不同的动词分别选用介词to 或for：(1) 在give, pass, hand, lend, send, tell, bring, show, pay, read, return, write, offer, teach, throw 等之后接介词to。 如： 请把那本字典递给我。 正：Please hand me that dictionary. 正：Please hand that dictionary to me. 她去年教我们的音乐。 正：She taught us music last year. 正：She taught music to us last year. (2) 在buy, make, get, order, cook, sing, fetch, play, find, paint, choose,prepare, spare 等之后用介词for 。如： 他为我们唱了首英语歌。 正：He sang us an English song. 正：He sang an English song for us. 请帮我把钥匙找到。 正：Please find me the keys. 正：Please find the keys for me. 能耽搁你几分钟吗(即你能为我抽出几分钟吗)? 正：Can you spare me a few minutes? 正：Can you spare a few minutes for me? 注：有的动词由于搭配和含义的不同，用介词to 或for 都是可能的。如：do sb a favour＝do a favour for sb 帮某人的忙 do sb harm＝do harm to sb 对某人有害
for的用法： 1. 表示“当作、作为”。如: I like some bread and milk for breakfast. 我喜欢把面包和牛奶作为早餐。 What will we have for supper? 我们晚餐吃什么? 2. 表示理由或原因,意为“因为、由于”。如: Thank you for helping me with my English. 谢谢你帮我学习英语。 Thank you for your last letter. 谢谢你上次的来信。 Thank you for teaching us so well. 感谢你如此尽心地教我们。 3. 表示动作的对象或接受者,意为“给……”、“对…… (而言)”。如: Let me pick it up for you. 让我为你捡起来。 Watching TV too much is bad for your health. 看电视太多有害于你的健康。 4. 表示时间、距离,意为“计、达”。如:
I usually do the running for an hour in the morning. 我早晨通常跑步一小时。 We will stay there for two days. 我们将在那里逗留两天。 5. 表示去向、目的,意为“向、往、取、买”等。如: Let’s go for a walk. 我们出去散步吧。 I came here for my schoolbag.我来这儿取书包。 I paid twenty yuan for the dictionary. 我花了20元买这本词典。 6. 表示所属关系或用途,意为“为、适于……的”。如: It’s time for school. 到上学的时间了。 Here is a letter for you. 这儿有你的一封信。 7. 表示“支持、赞成”。如: Are you for this plan or against it? 你是支持还是反对这个计划? 8. 用于一些固定搭配中。如:
1.表示各种“目的”，用for （1）What do you study English for 你为什么要学英语？ （2）went to france for holiday. 她到法国度假去了。 （3）These books are written for pupils. 这些书是为学生些的。 （4）hope for the best, prepare for the worst. 作最好的打算，作最坏的准备。 2．“对于”用for （1）She has a liking for painting. 她爱好绘画。 （2）She had a natural gift for teaching. 她对教学有天赋/ 3．表示“赞成、同情”，用for （1）Are you for the idea or against it 你是支持还是反对这个想法？ （2）He expresses sympathy for the common people.. 他表现了对普通老百姓的同情。 （3）I felt deeply sorry for my friend who was very ill. 4. 表示“因为，由于”（常有较活译法），用for （1）Thank you for coming. 谢谢你来。
（2）France is famous for its wines. 法国因酒而出名。 5．当事人对某事的主观看法，“对于（某人），对…来说”，（多和形容词连用），用介词to，不用for. （1）He said that money was not important to him. 他说钱对他并不重要。 （2）To her it was rather unusual. 对她来说这是相当不寻常的。 （3）They are cruel to animals. 他们对动物很残忍。 6．和fit, good, bad, useful, suitable 等形容词连用，表示“适宜，适合”，用for。（1）Some training will make them fit for the job. 经过一段训练，他们会胜任这项工作的。 （2）Exercises are good for health. 锻炼有益于健康。 （3）Smoking and drinking are bad for health. 抽烟喝酒对健康有害。 （4）You are not suited for the kind of work you are doing. 7. 表示不定式逻辑上的主语，可以用在主语、表语、状语、定语中。 （1）It would be best for you to write to him. （2） The simple thing is for him to resign at once.
常用介词用法(for-to-with-of)
For的用法 1. 表示“当作、作为”。如: I like some bread and milk for breakfast. 我喜欢把面包和牛奶作为早餐。 What will we have for supper? 我们晚餐吃什么? 2. 表示理由或原因,意为“因为、由于”。如: Thank you for helping me with my English. 谢谢你帮我学习英语。 3. 表示动作的对象或接受者,意为“给……”、“对…… (而言)”。如: Let me pick it up for you. 让我为你捡起来。Watching TV too much is bad for your health. 看电视太多有害于你的健康。 4. 表示时间、距离,意为“计、达”。如: I usually do the running for an hour in the morning. 我早晨通常跑步一小时。 We will stay there for two days. 我们将在那里逗留两天。
5. 表示去向、目的,意为“向、往、取、买”等。如: Let’s go for a walk. 我们出去散步吧。 I came here for my schoolbag.我来这儿取书包。 I paid twenty yuan for the dictionary. 我花了20元买这本词典。 6. 表示所属关系或用途,意为“为、适于……的”。如: It’s time for school. 到上学的时间了。 Here is a letter for you. 这儿有你的一封信。 7. 表示“支持、赞成”。如: Are you for this plan or against it? 你是支持还是反对这个计划? 8. 用于一些固定搭配中。如: Who are you waiting for? 你在等谁? For example, Mr Green is a kind teacher. 比如,格林先生是一位心地善良的老师。
加入收藏夹 主题： 介词试题It’s + 形容词 + of sb. to do sth.和It’s + 形容词 + for sb. to do sth.的用法区别。 内容： It's very nice___pictures for me. A.of you to draw B.for you to draw C.for you drawing C.of you drawing 提交人：杨天若时间：1/23/2008 20:5:54 主题：for 与of 的辨别 内容：It's very nice___pictures for me. A.of you to draw B.for you to draw C.for you drawing C.of you drawing 答：选A 解析：该题考查的句型It’s + 形容词+ of sb. to do sth.和It’s +形容词+ for sb. to do sth.的用法区别。 “It’s + 形容词+ to do sth.”中常用of或for引出不定式的行为者，究竟用of sb.还是用for sb.，取决于前面的形容词。 1) 若形容词是描述不定式行为者的性格、品质的，如kind，good，nice，right，wrong，clever，careless，polite，foolish等，用of sb. 例： It’s very kind of you to help me. 你能帮我，真好。 It’s clever of you to work out the maths problem. 你真聪明，解出了这道数学题。 2) 若形容词仅仅是描述事物，不是对不定式行为者的品格进行评价，用for sb.，这类形容词有difficult，easy，hard，important，dangerous，（im）possible等。例： It’s very dangerous for children to cross the busy street. 对孩子们来说，穿过繁忙的街道很危险。 It’s difficult for u s to finish the work. 对我们来说，完成这项工作很困难。 for 与of 的辨别方法： 用介词后面的代词作主语，用介词前边的形容词作表语，造个句子。如果道理上通顺用of，不通则用for. 如： You are nice.(通顺，所以应用of)。 He is hard.(人是困难的，不通，因此应用for.) 由此可知，该题的正确答案应该为A项。 提交人：f7_liyf 时间：1/24/2008 11:18:42
1. 两者都可以引出间接宾语，但要根据不同的动词分别选用介词to 或for： (1) 在give, pass, hand, lend, send, tell, bring, show, pay, read, return, write, offer, teach, throw 等之后接介词to。 如： 请把那本字典递给我。 正：Please hand me that dictionary. 正：Please hand that dictionary to me. 她去年教我们的音乐。 正：She taught us music last year. 正：She taught music to us last year. (2) 在buy, make, get, order, cook, sing, fetch, play, find, paint, choose,prepare, spare 等之后用介词for 。如： 他为我们唱了首英语歌。 正：He sang us an English song. 正：He sang an English song for us. 请帮我把钥匙找到。 正：Please find me the keys. 正：Please find the keys for me. 能耽搁你几分钟吗(即你能为我抽出几分钟吗)? 正：Can you spare me a few minutes? 正：Can you spare a few minutes for me? 注：有的动词由于搭配和含义的不同，用介词to 或for 都是可能的。如： do sb a favou r do a favour for sb 帮某人的忙 do sb harnn= do harm to sb 对某人有害
to和for的用法有什么不同（一） 一、引出间接宾语时的区别 两者都可以引出间接宾语，但要根据不同的动词分别选用介词to 或for，具体应注意以下三种情况： 1. 在give, pass, hand, lend, send, tell, bring, show, pay, read, return, write, offer, teach, throw 等之后接介词to。如： 请把那本字典递给我。 正：Please hand me that dictionary. 正：Please hand that dictionary to me. 她去年教我们的音乐。 正：She taught us music last year. 正：She taught music to us last year. 2. 在buy, make, get, order, cook, sing, fetch, play, find, paint, choose, prepare, spare 等之后用介词for 。如： 他为我们唱了首英语歌。 正：He sang us an English song. 正：He sang an English song for us. 请帮我把钥匙找到。 正：Please find me the keys. 正：Please find the keys for me. 能耽搁你几分钟吗(即你能为我抽出几分钟吗)? 正：Can you spare me a few minutes?
正：Can you spare a few minutes for me? 3. 有的动词由于用法和含义不同，用介词to 或for 都是可能的。如： do sb a favor＝do a favor for sb 帮某人的忙 do sb harm＝do harm to sb 对某人有害 在有的情况下，可能既不用for 也不用to，而用其他的介词。如： play sb a trick＝play a trick on sb 作弄某人 请比较： play sb some folk songs＝play some folk songs for sb 给某人演奏民歌 有时同一个动词，由于用法不同，所搭配的介词也可能不同，如leave sbsth 这一结构，若表示一般意义的为某人留下某物，则用介词for 引出间接宾语，即说leave sth for sb；若表示某人死后遗留下某物，则用介词to 引出间接宾语，即说leave sth to sb。如： Would you like to leave him a message? / Would you like to leave a message for him? 你要不要给他留个话？ Her father left her a large fortune. / Her father left a large fortune to her. 她父亲死后给她留下了一大笔财产。 二、表示目标或方向的区别 两者均可表示目标、目的地、方向等，此时也要根据不同动词分别对待。如： 1. 在come, go, walk, move, fly, ride, drive, march, return 等动词之后通常用介词to 表示目标或目的地。如： He has gone to Shanghai. 他到上海去了。 They walked to a river. 他们走到一条河边。
keep的用法 1. 用作及物动词 ①意为"保存；保留；保持；保守"。如： Could you keep these letters for me, please? 你能替我保存这些信吗？ ②意为"遵守；维护"。如： Everyone must keep the rules. 人人必须遵守规章制度。 The teacher is keeping order in class.老师正在课堂上维持秩序。 ③意为"使……保持某种(状态、位置或动作等)"。这时要在keep的宾语后接补足语，构 成复合宾语。其中宾语补足语通常由形容词、副词、介词短语、现在分词和过去分词等充当。如： 例：We should keep our classroom clean and tidy.(形容词) 我们应保持教室整洁干净。 You'd better keep the child away from the fire.(副词)你最好让孩子离火远一点。 The bad weather keeps us inside the house.(介词短语)坏天气使我们不能出门。 Don't keep me waiting for long.(现在分词)别让我等太久。 The other students in the class keep their eyes closed.(过去分词) 班上其他同学都闭着眼睛。 2. 用作连系动词 构成系表结构：keep＋表语，意为"保持，继续(处于某种状态)"。其中表语可用形容词、副词、介词短语等充当。如： 例：You must look after yourself and keep healthy.(形容词) 你必须照顾好自己，保持身体健康。 Keep off the grass.(副词)请勿践踏草地。 Traffic in Britain keeps to the left.(介词短语)英国的交通是靠左边行驶的。 注意：一般情况下，keep后接形容词较为多见。再如： She knew she must keep calm.她知道她必须保持镇静。 Please keep silent in class.课堂上请保持安静。 3. ①keep doing sth. 意为"继续干某事"，表示不间断地持续干某事，keep后不 能接不定式或表示静止状态的v-ing形式，而必须接延续性的动词。 例：He kept working all day, because he wanted to finish the work on time. 他整天都在不停地工作，因为他想准时完成工作。 Keep passing the ball to each other, and you'll be OK.坚持互相传球，你们就
202X中考英语：to和for的区别与用法中考栏目我为考生们整理了“202X中考英语：to和for的区别与用法”，希望能帮到大家，想了解更多考试资讯，本网站的及时更新哦。 202X中考英语：to和for的区别与用法 to和for的区别与用法是什么 一般情况下, to后面常接对象; for后面表示原因与目的为多。 Thank you for helping me. Thanks to all of you. to sb. 表示对某人有直接影响比如，食物对某人好或者不好就用to; for 表示从意义、价值等间接角度来说，例如对某人而言是重要的，就用for. for和to这两个介词，意义丰富，用法复杂。这里仅就它们主要用法进行比较。 1. 表示各种“目的” 1. What do you study English for? 你为什么要学英语? 2. She went to france for holiday. 她到法国度假去了。 3. These books are written for pupils. 这些书是为学生些的。 4. hope for the best, prepare for the worst. 作最好的打算，作最坏的准备。
2.对于 1.She has a liking for painting. 她爱好绘画。 2.She had a natural gift for teaching. 她对教学有天赋。 3.表示赞成同情，用for不用to. 1. Are you for the idea or against it? 你是支持还是反对这个想法? 2. He expresses sympathy for the common people.. 他表现了对普通老百姓的同情。 3. I felt deeply sorry for my friend who was very ill. 4 for表示因为，由于(常有较活译法) 1.Thank you for coming. 谢谢你来。 2. France is famous for its wines. 法国因酒而出名。 5.当事人对某事的主观看法，对于(某人)，对?来说(多和形容词连用)用介词to，不用for.. He said that money was not important to him. 他说钱对他并不重要。 To her it was rather unusual. 对她来说这是相当不寻常的。 They are cruel to animals. 他们对动物很残忍。
to , of 和for的区别 1.to有到的意思，常常和go，come，get连用引出地点。Go to school , go to the shop , go to the cinema. 常见的短语：the way to 去---的路 On one’s way to 在某人去---的路上 以上的用法中，当地点是副词home，here，there等是to 要去掉。如：get home，the way here To后跟动词原形，是不定式的标志 It is +形容词+(for/of +人+)to do sth.(括号内部分可以省略) It is easy for me to learn English. It is very kind of you to lend me your money. 当形容词表示人的行为特征时用of表示to do的性质时用for Want, hope ,decide, plan , try , fail等词后跟to do I want to join the swimming club. Would like to do I’d like to play basketball with them. It is time to have a break. Next to , close to , from ---to--- 2.for 为，表示目的。 Thank you for Buy sth for sb =buy sb sth It is time for bed. Here is a letter for you.
I will study for our country. 3.of表示所属关系意思是：---的 a map of the world a friend of mine
for和of引导的不定式结构的区别 不定式是一种非谓语动词，不能单独作谓语，因此没有语法上的主语。但由于不定式表示的是动作，在意义上可以有它的主体。我们称之为逻辑主语。 提起不定式逻辑主语，人们首先想到的会是“for+名词（宾格代词）+不定式”的复合结构。如：It is important for us to study English well．然而，有时不定式的逻辑主语须要用“of+名词（代词宾格）”才行。例如：It is kind of you to help me．而不能说：It is kind for you to help me．在选择介词“for”还是“of”时，人们往往总是凭感觉而定。有时受习惯影响，多选介词“for”。于是常出现这样的错误：It was careless for him to lose his way．It is cruel for you to do so．由于众多语法书对这种结构中使用“for”与“of”的区别介绍甚少，一些人对其概念认识尚不完全清楚，笔者认为有必要就这一问题作些探讨与介绍。 一、在句中的语法作用不同 a．不定式for结构在句中可以作主、宾、表、定、状、同位语： 1．It is easy for Tom to do this work．（主语）汤姆做此工作是容易的。 2．I'd like for him to come here．（宾语）我喜欢他来这里。 3．His idea is for us to travel in two different groups．（表语）他的想法是：我们分成两组旅行。 4．Have you heard about the plan for you to go abroad．（定语）你听到让你出国的计划吗？ 5．The word is too difficult for him to pronounce well．（状语）这单词太难，他念不准。 6．In the most schools，it is the custom for the headmaster to declare the newterm start．在大部分学校，校长宣布新学期开始是一个习惯。 b．不定式of结构只能在句中作主语。 1．It was careless of him to leave his umbrella in the train．他把伞丢在火车上真是太粗心了。 2．It is awfully good of you to come to see me off at the station．谢谢你来车站送我。 二、逻辑主语的名词有所不同