a r
X
i
v
:a
s t
r o
-
p
h
/
4
5
5
1
4v
1
2
6
M
a
y
2
4
Can Supermassive Black Holes Su?ciently Heat Cool Cores of Galaxy Clusters?Yutaka Fujita 1,2,and Thomas H.Reiprich 3yfujita@th.nao.ac.jp ABSTRACT Activities of a supermassive black hole or active galactic nucleus in the cen-tral galaxy of a cluster of galaxies have been promising candidates for heating sources of cool cluster cores.We estimate the masses of black holes using known correlations between the mass of a black hole and the velocity dispersion or the luminosity of the host galaxy.We ?nd that the masses are ～108?9M ⊙and the central X-ray luminosities of the host clusters (“the strength of the cooling ?ow”)are well below the Eddington luminosities.However,we do not ?nd a correlation between the mass and the central X-ray luminosity of the host cluster.If the heating is stable,this seems to contradict a simple expectation if supermassive black holes are the main heating source of a cluster core.Moreover,if we assume a canonical energy conversion rate (10%),black holes alone are unable to su?-ciently heat the clusters with strong centrally peaked X-ray emission (“massive cooling ?ows”)over the lifetime of cluster cores.These results may indicate that massive cooling ?ows are a transient phenomenon,which may be because the black holes are activated periodically.Alternatively,in the massive cooling ?ow clusters,the energy conversion rate may be larger than 10%,that is,the black holes may be Kerr black holes.
Subject headings:galaxies:active—cooling ?ows—galaxies:jets—galaxies:nu-clei
1.Introduction
Clusters of galaxies are the largest gravitationally bound virialized objects in the uni-verse.They are?lled with hot X-ray gas with temperatures of～2–10keV.The gas is thought to be heated by the energy released when clusters gravitationally collapsed.While the gas cooling through the X-ray radiation is ine?cient in most regions of a cluster,it is very e?cient in the central region because of the high gas density.From X-ray observations, it can be estimated that the thermal energy of the gas within cluster cores is lost radiatively within～108?9yr.The gas cooling should decrease the temperature and pressure of the gas at the cluster cores,and the weight of the overlying gas should produce gas?ows toward the cluster centers.The?ows are called“cooling?ows”and the idea has prevailed for about30 years(Fabian1994).
Recent X-ray observations showed that the gas in the central regions of clusters is not cooling as much as previously believed.This is indicated by the lack of metal line emission that is characteristic of cooling X-ray gas(e.g.Ikebe et al.1997;Makishima et al.2001; Peterson et al.2001;Tamura et al.2001;Kaastra et al.2001;Matsushita et al.2002).This means that the above simple cooling?ow picture is not correct and that there must be some heating sources balancing the energy loss through X-ray emission in the central regions of clusters.
There are several heating models such as heat conduction(e.g.Takahara&Takahara 1981;Tucker&Rosner1983;Friaca1986;Gaetz1989;B¨o hringer&Fabian1989;Sparks1992; Saito&Shigeyama1999;Narayan&Medvedev2001),acoustic waves propagating from the outside of a cluster core(Fujita,Suzuki,&Wada2004),or magnetohydrodynamic(MHD) e?ects(Makishima et al.2001).At present,the most promising candidate for the heating source is the supermassive black hole at the center of the giant elliptical cluster-center galaxy (e.g.Tucker&Rosner1983;Rephaeli1987;B¨o hringer&Mor?ll1988;Binney&Tabor1995; Soker et al.2001;Ciotti&Ostriker2001;B¨o hringer et al.2002;Churazov et al.2002;Soker, Blanton,&Sarazin2002;Reynolds,Heinz,&Begelman2002;Kaiser&Binney2003).In fact,the Chandra X-ray observatory has shown that the strong activities of the supermassive black holes disturb hot X-ray gas in the central regions of clusters(e.g.Fabian et al.2000; McNamara et al.2000;Blanton et al.2001;McNamara et al.2001;Mazzotta et al.2002; Fujita et al.2002;Johnstone et al.2002;Kempner,Sarazin,&Ricker2002;Takizawa et al. 2003).In many clusters,bubbles of high energy particles have been found;it is expected that jets produced by the supermassive black holes in?ate those bubbles.Moreover,numerical simulations have suggested that the bubbles move outward in a cluster by buoyancy,thus mixing the surrounding hot X-ray gas(e.g.Churazov et al.2001;Quilis,Bower,&Balogh 2001;Saxton,Sutherland,&Bicknell2001;Br¨u ggen&Kaiser2002;Basson&Alexander
2003).As a result of the mixing,hot X-ray gas in the outer region of the cluster is brought into,and subsequently heats the cluster center.Moreover,Chandra found that acoustic waves formed through jet activities are propagating in the hot X-ray gas of the Perseus cluster(Fabian et al.2003).Through the viscosity of the gas,the waves may heat the surrounding gas.
The mass of a supermassive black hole generally needs to be large(～109?10M⊙)to balance the cooling of X-ray gas regardless of the actual heating mechanism(e.g.bubbles, waves,and so on),if the strong X-ray emission from the cluster is not a transient phe-nomenon(Fabian,Voigt,&Morris2002).Moreover,relatively high heating e?ciency may be required.For example,assuming Bondi accretion,XMM-Newton observations showed that the supermassive black hole at the center of the Virgo cluster has to convert5%of the rest mass of the accreted gas into thermal energy of the surrounding gas to prevent cooling at least at present(Churazov et al.2002,see also Di Matteo et al.2003).This is close to a canonical value that is often used in this kind of studies(～10%).In this paper,we derive the masses of supermassive black holes and compare the maximum energy they can produce with the total energy released as X-rays from the central regions of the clusters.In this paper,we assume h=0.7(H0=100h km s?1Mpc?1),?0=0.3,andΛ=0.7unless otherwise noted.
2.Samples and Analysis
2.1.Black Hole Masses
We study53clusters that have been observed with the ROSAT satellite(Peres et al. 1998),and belong to the X-ray?ux limited sample of55clusters(Edge,Stewart,&Fabian 1992).Unfortunately,clusters of galaxies are generally distant,and the mass of the super-massive black hole at the center of a cluster cD galaxy has been directly measured only for a few clusters.However,it has been known that the mass of the black hole is related to the properties of the host https://www.doczj.com/doc/a111028415.html,ing HST and other observations,the relations have been determined more exactly than early studies(e.g.Magorrian et al.1998).In this paper,we use the relations between the black hole and the host galaxy to obtain the black hole mass. The mass of the supermassive black hole at the center of a cluster cD galaxy can be obtained from empirical M BH–σand M BH–M R relations,where M BH is the mass of a supermassive black hole,σis the velocity dispersion of stars in the host galaxy,and M R is the R-band absolute magnitude of the host galaxy.For the M BH–σrelation,we adopt
log(M BH/M⊙)=(8.12±0.07)+(3.75±0.3)log(σ/200km s?1)(1)
(Gebhardt et al.2000),and for the M BH–M R relation,we adopt
log(M BH/M⊙)=?(0.50±0.02)M R?(3.33±0.48)(2) (McLure&Dunlop2002).The coe?cients are slightly di?erent from those in the original papers because of di?erences in the assumed cosmological parameters.There are more recent studies of the M BH–σrelation that give steeper slopes;Tremaine et al.(2002)obtained4.02 and Ferrarese(2002)found4.58.Tremaine et al.(2002)discussed the di?erence between Tremaine et al.(2002)and Ferrarese(2002)and indicated that the large value obtained by Ferrarese(2002)is due to inappropriate treatment of central velocity dispersion.We con?rmed that the di?erence between Gebhardt et al.(2000)and Tremaine et al.(2002)is so small that it does not a?ect the results in this paper(see Figure26in Pinkney et al. 2003).More recently,Pinkney et al.(2003)studied the M BH–σrelation only for early-type galaxies and the slope they obtained is almost the same as that obtained by Gebhardt et al. (2000),although the number of galaxies in the sample is only10.From these reasons,we use the result of Gebhardt et al.(2000).The optical data for the galaxies at cluster centers,such as the velocity dispersions and absolute magnitudes,are obtained from the HYPERLEDA database1.If there are several measurements for a given cluster,we adopted the latest one. Among the53clusters,the velocity dispersions of the central galaxies are measured for29 clusters.Since there are only14galaxies for which the R-band magnitudes are obtained,we use B-band magnitudes for other galaxies;B-band magnitudes have been measured for40 galaxies including the above14galaxies.For the galaxies for which only B-band magnitudes are obtained,the B-band magnitudes are transformed to the R-band magnitudes using B–R color,where the color is assumed to be the average of the14galaxies,B–R=1.67±0.01. The black hole masses are shown in Table1;the black hole mass derived from the M BH–σrelation is referred to as M BH,σand that derived from the M BH–M R relation is referred to as
M BH,M
R .There are43clusters for which M BH,σor M BH,M
R
can be determined.The errors
in the black hole masses are calculated using the worst case ranges given in equations(1) and(2).
2.2.X-Ray Luminosities
In addition to comparing current X-ray luminosities of clusters and the masses of the central black holes,we compare the total energy released in X-rays from the central region of clusters throughout the cluster lifetime with the maximum energy that the black holes can
supply.We use the ROSAT data obtained by Peres et al.(1998).While data from Chandra and XMM-Newton might be better suited for our purpose,ROSAT data are the only ones available for a su?ciently large number of clusters to conduct a statistically relevant uniform study.
The hot gas in a cluster core loses its thermal energy through X-ray emission.Without an energy supply,the gas temperature would go to zero within～108?9yr(Fabian1994). The total energy that must be supplied to prevent the cooling depends on the age of the cluster core(t age),which should be larger than that of the cluster itself.In this paper,we assume that cluster cores formed at z～1because numerical simulations indicated that X-ray emission from a cluster has not changed much since then(Eke,Navarro,&Frenk 1998),and because a signi?cant part of the X-ray emission from a cluster comes from its central region including the core.Note that the simulations done by Eke et al.(1998)include neither cooling nor heating.The hot gas in the central region of a cluster is generally in pressure equilibrium with the gravity of dark matter because of the small sound crossing time.Therefore,the simulations done by Eke et al.(1998)indicate that the gravitational structure of cluster cores formed at z～1.In actual clusters,observations suggest that both cooling and heating are e?ective but they appear to be well balanced(Peterson et al.2001; Tamura et al.2001;Kaastra et al.2001).In fact,Allen,Schmidt,&Fabian(2001)showed that temperature pro?les among clusters are similar and that the central temperatures drop only a factor of1/2even for“cooling?ow clusters”(see also Ikebe2001).Although there is no consensus on the mechanism that keeps the balance(for thermal conduction,see Ruszkowski &Begelman2002;Kim&Narayan2003),the balanced cooling and heating may mean that the gas motion in the central regions of clusters is slow and that the X-ray emission from cluster cores re?ects the gravitational structure there,which formed at z～1.Since there is no reason that z=0is a special epoch,we assume that the cooling and heating have been balanced since the formation of the cluster core,and thus we assume that the X-ray emission from the core has not changed much since z～1.In fact,Valdarnini(2002) performed numerical simulations including both cooling and heating and showed that the X-ray luminosity of a cluster has not changed or even has decreased since z～1.2(high resolution simulations in his Figure11).The heating sources of the gas in these simulations are supernovae,not supermassive black holes.However,since the radiatively cooled gas is the fuel for both sources,the results should be at least qualitatively the same.The reason for the decrease in X-ray luminosity is that radiative cooling dominates heating before enough stars are formed out of the cooled gas.After the cooling and heating are balanced,the central gas density and X-ray luminosity of the cluster decrease.Therefore,although we estimate the required energy supply from a black hole,assuming that the X-ray luminosity of a cluster core has been unchanged for z 1,the supply may be underestimated if we?x
the X-ray luminosity at the observed value at z ～0.
On the other hand,semi-analytic models of galaxy formation predict that the supermas-sive black holes at galaxy centers gain most of their mass at z 1–2(Haehnelt &Kau?mann 2002;Hatziminaoglou et al.2003;Volonteri,Haardt,&Madau 2003).Thus,we also assume that the formation epoch of the supermassive black holes is z ～1.
Since we assume that cluster cores formed at z ～1,the hot X-ray gas within radii where the cooling time of the gas is t age =7.7Gyr (the look-back time for z =1)must be heated.Peres et al.(1998)listed the X-ray luminosities of 53clusters within radii where the cooling time of hot X-ray gas is 13Gyr.In a classical cooling ?ow model,the central X-ray luminosity is correlated with the strength of the cooling ?ow (Fabian 1994).We modify the central X-ray luminosities listed by Peres et al.(1998)into those for the cooling time of
7.7Gyr to estimate the energy supplied by supermassive black holes.
In order to modify the central X-ray luminosity,we need to ?nd the density pro?le of the X-ray gas in a cluster.We assume that a cluster is isothermal.For “cooling ?ow clusters,”Chandra observations showed that the temperature at the center is ～1/2of the average (Allen et al.2001).However,this temperature drop does not a?ect photon counts in the ROSAT band (at most ～10%,see Mohr et al.1999).A parametric description of the cluster gas density pro?le has often been used,and it is called the β-model (e.g.Cavaliere &Fusco-Femiano 1976).Assuming spherical symmetry,the model
S X (R )=S 0 1+
R 2
r 2c ?3β/2.(4)
If excess emission (so-called cooling ?ow)is seen in the innermost region of a cluster,the surface pro?le can be ?tted with two β-model functions
S X (R )=S 01 1+R 2r 2c 2
?3β2+1/2,(5)where r c 1
ρgas (r )2=ρ2gas ,0,1 1+r 2r 2c 2 ?3β2,(6)
whereρgas,0,1>ρgas,0,2.
The results of the?ts are shown in Table2;the results of single-β-model?ts are rep-resented by subscript2.Among106clusters investigated by Reiprich&B¨o hringer(2002), there are24clusters that overlap with the53clusters studied by Peres et al.(1998)and that the qualities of the data are high enough.For these clusters,we?t the surface bright-ness with twoβmodels without the assumption ofβ1=β2and obtain the density pro?le (equation[6]).The selection criteria of the clusters with high data quality are(1)ROSAT PSPC pointed observations had been made,and(2)S02>0and S01>S02.These clusters are indicated by‘RB2’in Table2.
Among the remaining,22clusters were studied by Mohr,Mathiesen,&Evrard(1999). For the clusters with central excess,they?t the surface brightness and obtain density pro?les assuming thatβ1=β2.Since they presented only the central gas density,ρgas,obs,0,for the clusters with a central excess,we estimateρgas,0,1andρgas,0,2by solving equations
ρ2gas,0,1+ρ2gas,0,2=ρ2gas,obs,0,(7)
ρgas,0,2= S02r c1
ρgas(r[t cool=13?h?1/2Gyr])=
13?h?1/2
Here r(t cool=13?h?1/2Gyr)corresponds to r cool,P/?h.We de?ne r cool,FR≡r(t cool=7.7Gyr) to be discriminated from r cool,P.
Peres et al.(1998)also derived X-ray luminosities of clusters within their cooling radii, L P( L FR( other hand,L FR( There are two possibilities to overcome this di?culty.One is that the radiative e?ciency ηis larger than the canonical value(0.1).This happens if the black holes are rapidly rotating Kerr black holes.In this case,the maximum value ofηis0.42,based on the binding energy of particles on the innermost stable circular orbit(Shapiro&Teukolsky1983).Moreover, Kerr holes also alter the energy that can be stored and extracted from the black holes(e.g. via the Blandford-Znajek mechanism).The other possibility is that a massive cooling?ow or strong X-ray emission from a cluster core is a transient event.This may also be consistent with the fact that there is no correlation between the mass of a black hole and the X-ray luminosity of a cluster(Figure2),which may indicate that the cooling and heating at the cluster center are not exactly balanced(see Soker et al.2001).Here,we assume that the supermassive black holes we selected are an unbiased sample of the whole supermassive black hole population,and that the average of the energy conversion rates,ε,can be regarded as the time-average of the conversion rate for a black hole.However,since our cluster sample is ?ux-limited,the bright clusters tend to be preferentially selected.In order to correct for this e?ect,we take the average ofεby weighting with1/V max,where V max is the maximum volume within which clusters with a given luminosity can be observed.The volume is represented by ,where L X is the total X-ray luminosity of a cluster obtained from David et al. V max∝L3/2 X (1993).For43clusters for which we could estimate the mass of supermassive black holes,the ×10?2.Moreover,we describe below how we correct average conversion rate is ε =6.4+4.7 ?1.6 the bias attributed to the10clusters for which we could not estimate the black hole masses. The X-ray luminosity and the back hole mass of a cluster are not correlated(Figure2),and the average black hole mass for the43clusters is6.3×108M⊙.Assuming that the black hole mass for the remaining10clusters is the same as the average mass,we can estimate εfor these clusters.If we include these10clusters,the average of the conversion rate is ×10?2.Since ε is much smaller than one,the supermassive black holes can ε =6.6+4.7 ?1.6 heat the surrounding hot X-ray gas of the clusters unless the past X-ray luminosities were 20times larger than the current values.Some of the results of numerical simulations by Valdarnini(2002)show that the X-ray luminosity of a cluster is increasing toward higher redshift(high resolution simulations in his Figure11).However,the increase is at most a factor of10. There is one more possibility;the M BH–σand M BH–M R relations we used may not apply to the supermassive black holes in the cD galaxies in clusters.As far as we know, there are two clusters for which the masses of the supermassive black holes have been directly measured.One is the Virgo cluster and the other is Cygnus A.The mass of the supermassive back hole at the center of the Virgo cluster is(3.2±0.9)×109M⊙(Macchetto et al.1997) and that of Cygnus A is(2.5±0.7)×109M⊙(Tadhunter et al.2003).On the other hand, the masses obtained from the M BH–σrelation are3.1+11.3 ?2.5×108M⊙and3.3+12.0 ?2.6 ×108M⊙, respectively(Table1).Thus,the values obtained from the M BH–σrelation are signi?cantly smaller than those directly measured.However,since there are only two samples,it is premature to conclude that the discrepancy generally exists for cD galaxies. 4.Conclusions We estimated the masses of supermassive black holes,M BH,at the centers of43clusters of galaxies included in an X-ray?ux limited sample.We showed that M BH～108?9M⊙using an empirical relation between M BH and the velocity dispersion(or the luminosity) of the host galaxy.The central X-ray luminosities of the host clusters are well below the Eddington luminosities.We found that there is no correlation between M BH and the central X-ray luminosity of the cluster core.This seems to contradict a simple expectation if a supermassive black hole is the main heating source of the cluster core.We also showed that strong X-ray emission observed in some cluster cores may not be sustained by the heating by supermassive black holes for the ages of the cluster cores.These results may indicate that the strong X-ray emission is a transient phenomenon,which may be because the black hole activities are periodic.Moreover,the clusters with the strong X-ray emission may be very e?ectively heated by Kerr black holes. We thank the anonymous referee for useful suggestions.We also thank T.E.Clarke, I.Tanaka,Y.Sato,M.Machida,K.Shimasaku,T.Goto,M.,Enoki,M.Nagashima,S. Iwamoto,N.Yoshida,K.Asano,and M.Kino for useful comments.Y.F.was supported in part by a Grant-in-Aid from the Ministry of Education,Culture,Sports,Science,and Technology of Japan(14740175).T.H.R.acknowledges support by the Celerity Foundation through a postdoctoral fellowship. REFERENCES Allen,S.W.,Schmidt,R.W.,&Fabian,A.C.2001,MNRAS,328,L37 Basson,J.F.&Alexander,P.2003,MNRAS,339,353 Binney,J.,&Tabor,G.1995,MNRAS,276,663 Blanton,E.L.,Sarazin,C.L.,McNamara,B.R.,&Wise,M.W.2001,ApJ,558,L15 B¨o hringer,H.&Fabian,A.C.1989,MNRAS,237,1147 B¨o hringer,H.,Matsushita,K.,Churazov,E.,Ikebe,Y.,&Chen,Y.2002,A&A,382,804 B¨o hringer,H.,&Mor?ll,G.E.1988,ApJ,330,609 Br¨u ggen,M.&Kaiser,C.R.2002,Nature,418,301 Cavaliere,A.,&Fusco-Femiano,R.1976,A&A,49,137 Churazov,E.,Br¨u ggen,M.,Kaiser,C.R.,B¨o hringer,H.,&Forman,W.2001,ApJ,554, 261 Churazov,E.,Sunyaev,R.,Forman,W.,&B¨o hringer,H.2002,MNRAS,332,729 Ciotti,L.,&Ostriker,J.P.2001,ApJ,551,131 David,L.P.,Slyz,A.,Jones,C.,Forman,W.,Vrtilek,S.D.,&Arnaud,K.A.1993,ApJ, 412,479 Di Matteo,T.,Allen,S.W.,Fabian,A.C.,Wilson,A.S.,&Young,A.J.2003,ApJ,582, 133 Edge,A.C.,Stewart,G.C.,&Fabian,A.C.1992,MNRAS,258,177 Eke,V.R.,Navarro,J.F.,&Frenk,C.S.1998,ApJ,503,569 Fabian,A.C.1994,ARA&A,32,277 Fabian,A.C.et al.2000,MNRAS,318,L65 Fabian,A.C.,Sanders,J.S.,Allen,S.W.,Crawford,C.S.,Iwasawa,K.,Johnstone,R.M., Schmidt,R.W.,&Taylor,G.B.2003,MNRAS,344,L43 Fabian,A.C.,Voigt,L.M.,&Morris,R.G.2002,MNRAS,335,L71 Ferrarese,L.2002,in Current High-Energy Emission around Black Holes,ed.C.-H.Lee (Singapore:World Scienti?c) Friaca,A.C.S.1986,A&A,164,6 Fujita,Y.,Sarazin,C.L.,Kempner,J.C.,Rudnick,L.,Slee,O.B.,Roy,A.L.,Andernach, H.,&Ehle,M.2002,ApJ,575,764 Fujita,Y.,Suzuki,T.K.,&Wada,K.2004,ApJ,600,650 Gaetz,T.J.1989,ApJ,345,666 Gebhardt,K.et al.2000,ApJ,539,L13 Haehnelt,M.G.&Kau?mann,G.2002,MNRAS,336,L61 Hatziminaoglou,E.,Mathez,G.,Solanes,J.,Manrique,A.,&Salvador-Sol′e,E.2003,MN-RAS,343,692 Ikebe,Y.2001,Two Years of Science with Chandra,Abstracts from the Symposium held in Washington,DC,5-7September,2001., Ikebe,Y.et al.1997,ApJ,481,660 Johnstone,R.M.,Allen,S.W.,Fabian,A.C.,&Sanders,J.S.2002,MNRAS,336,299 Kaastra,J.S.,Ferrigno,C.,Tamura,T.,Paerels,F.B.S.,Peterson,J.R.,&Mittaz,J.P.D. 2001,A&A,365,L99 Kaiser,C.R.,&Binney,J.2003,MNRAS,338,837 Kempner,J.C.,Sarazin,C.L.,&Ricker,P.M.2002,ApJ,579,236 Kim,W.&Narayan,R.2003,ApJ,596,889 Macchetto,F.,Marconi,A.,Axon,D.J.,Capetti,A.,Sparks,W.,&Crane,P.1997,ApJ, 489,579 Magorrian,J.,et al.1998,AJ,115,2285 Makishima,K.et al.2001,PASJ,53,401 Matsushita,K.,Belsole,E.,Finoguenov,A.,&B¨o hringer,H.2002,A&A,386,77 Mazzotta,P.,Kaastra,J.S.,Paerels,F.B.,Ferrigno,C.,Colafrancesco,S.,Mewe,R.,& Forman,W.R.2002,ApJ,567,L37 McLure,R.J.&Dunlop,J.S.2002,MNRAS,331,795 Narayan,R.&Medvedev,M.V.2001,ApJ,562,L129 McNamara,B.R.et al.2000,ApJ,534,L135 McNamara,B.R.et al.2001,ApJ,562,L149 Mohr J.J.,Mathiesen B.,and Evrard A.E.1999,ApJ,517,627 Neumann,D.M.,Lumb,D.H.,Pratt,G.W.,&Briel,U.G.2003,A&A,400,811 Peres,C.B.,Fabian,A.C.,Edge,A.C.,Allen,S.W.,Johnstone,R.M.,&White,D.A. 1998,MNRAS,298,416 Peterson,J.R.et al.2001,A&A,365,L104 Pinkney,J.et al.2003,ApJ,596,903 Quilis,V.,Bower,R.G.,&Balogh,M.L.2001,MNRAS,328,1091 Reiprich,T.H.&B¨o hringer,H.2002,ApJ,567,716 Rephaeli,Y.1987,MNRAS,225,851 Reynolds,C.S.,Heinz,S.,&Begelman,M.C.2002,MNRAS,332,271 Ruszkowski,M.&Begelman,M.C.2002,ApJ,581,223 Saito,R.,&Shigeyama,T.1999,ApJ,519,48 Saxton,C.J.,Sutherland,R.S.,&Bicknell,G.V.2001,ApJ,563, Shapiro,S.L.,&Teukolsky,S.A.1983,Black Holes,White Dwarfs,and Neutron Stars(New York:Wiley-Interscience) Soker,N.,Blanton,E.L.,&Sarazin,C.L.2002,ApJ,573,533 Soker,N.,White,R.E.,David,L.P.,&McNamara,B.R.2001,ApJ,549,832 Sparks,W.B.1992,ApJ,399,66 Tadhunter,C.,Marconi,A.,Axon,D.,Wills,K.,Robinson,T.G.,&Jackson,N.2003, MNRAS,342,861 Takahara,M.,&Takahara,F.1981,Prog.Theor.Phys.,65,L369 Takizawa,M.,Sarazin,C.L.,Blanton,E.L.,&Taylor,G.B.2003,ApJ,595,142 Tamura,T.et al.2001,A&A,365,L87 Tremaine,S.,et al.2002,ApJ,574,740 Tucker,W.H.&Rosner,R.1983,ApJ,267,547 Valdarnini,R.2002,ApJ,567,741 Volonteri,M.,Haardt,F.,&Madau,P.2003,ApJ,582,559 Table1.Cluster and Black Hole Parameters. ClusterσM R M BH,σM BH,M L FR( R (km s?1)(108M⊙)(108M⊙)(1044erg s?1) Table1—Continued L FR( R (km s?1)(108M⊙)(108M⊙)(1044erg s?1) a The R-band magnitude is determined from the B-band magnitude by B?R= 1.67. Table2.Fitting Parameters. Cluster zρgas,0,1ρgas,0,2r c1r c2β1β2ref a (10?27g cm?3)(10?27g cm?3)(kpc)(kpc) Table2—Continued Cluster zρgas,0,1ρgas,0,2r c1r c2β1β2ref a (10?27g cm?3)(10?27g cm?3)(kpc)(kpc) a References–RB1:oneβ-model?ts by Reiprich&B¨o hringer(2002),RB2:clusters in the catalogue of Reiprich&B¨o hringer(2002)?tted with twoβmodels,MME:Mohr et al.(1999),and M:Matsushita et al.(2002) 10M BH, σ (M M B H , M R ( Fig. 1.—Black hole mass derived from the M BH –σrelation (M BH ,σ)versus that derived from the M BH –M R relation (M BH ,M R )for 26clusters for which both velocity dispersion and absolute magnitude are measured.The line indicates M BH ,M R =M BH ,σ. 10L FR ( ε 10 10 L FR( Fig. 3.—The central X-ray luminosity of a cluster,L FR( with solid errors)or the M BH–M R relation(open circles with dotted errors). 全国2013年10月高等教育自学考试 高级英语试题 课程代码：00600 请考生按规定用笔将所有试题的答案涂、写在答题纸上。 选择题部分 注意事项： 1．答题前，考生务必将自己的考试课程名称、姓名、准考证号用黑色字迹的签字笔或钢笔填写在答题纸规定的位置上。 2．每小题选出答案后，用2B铅笔把答题纸上对应题目的答案标号涂黑。如需改动，用橡皮擦干净后，再选涂其他答案标号。不能答在试题卷上。 I. Each of the following sentences is given four choices of words or expressions. Choose the right one to complete the sentence and blacken the corresponding letter on your Answer Sheet. (15 points, 1 point for each) 1．Dorothy accepted the news of war with ______ and sadness. A． excitement B． commitment C． bewilderment D． embarrassment 2． The government could face defeat if it tries to push through the ______ proposals. A． doubtful B． conspicuous C． questionable D． controversial 3． This single market is designed to ______ barriers to the free movement of goods, services and people. A． terminate B． abolish C． eliminate D． exclude 4． He has emerged from being a(n) ______ and unsure candidate into a fluent debater. A． hesitant B． indifferent C． pleasant D． considerate 5．Large paintings can ______ the feeling of space in small rooms. A． endear B． enhance C． enlarge D． encourage Baby I love you 一咯尅马(拉)几慢 (内) 马额门问及哈那都就几安那 I want you I need you No勒 不勒几慢 I don’t know why I feel bad 你噶mong得 粗卡黑各涩他冷南夹（日）都慢那 掐得思米阿吉囧米得打慢 南尼噶就哇哈mion 各不你拉够 but 恰古话噶那baby 得且你噶mong得 Du du du du du du du du du du du du du oh oh oh oh oh Du du du du du du du du du du du du du oh oh oh oh oh Baby I miss you 为恰古no慢 森噶那他冷撒朗莫慢那 完哈吉安那 noe 撒狼哈嫩寄斗米我哈嫩寄斗 古不你安噶没一r 黑噶流阿吉都 I don’t know why I feel bad 你噶mong得 奴n 阿配阿江够流克mon瓜怕江 扣r mion 一共kiong无噶阿你吉强南求 怒股mo流 哦莫恩噶你囧没啦诶啦以 够里诶搜品喊散诶都流恩给那里 内给no也给mo 撒囧比散配给 古度得信撒bo林奴n木就进配给 为non 痕bo卡够难噗痕gi呀 （哈）嫩共得得策你噶mong得Du du du du du du du du du du du du du oh oh oh oh ohDu du du du du du du du du du du du du oh oh oh oh ohBaby I just want you backI want you back I want you bac kBaby I know it’s too late it just too late it just too lateBaby I just want you back I want you back I want you backBaby I know it’s too late it just too late it just too late 撒窝啦比咯黑哟就啦比咯 内给咯他洗头啦哇大啦够奴比咯 东内马打够里马打诶搜 跳叫大你没给嫩哟进马就疼得啦够一咯 （古）恰哈够几吉黑那won勒吉吉黑 木啦搜no都慢恰噶吉呀那本ki几北 内噶都恰啦给喊本慢那就勒 困恰ki 暗那给且白头啦哇就勒 Baby I hate you Baby I loved youMa baby hate youBaby love you du du du dudu 你噶mong得 2000年10月高级英语试题及答案 课程代码：0600 本试题分两部分，第一部分考核课程内容，1页至4页；选择题42分，非选择题18分。 第二部分考核水平，4页至8页；选择题20分，非选择题20分。本试题共8页，满分100分。考试时间150分钟。全部题目用英语作答（英语汉题目除外），并将答案写在答题纸的相应位置上，否则不记分。 Part One 1.The following paragraphs are taken from the textbooks, followed by a list of words or expressions marked A to X. Choose the one that best completes each of the sentences and write the corresponding letter on your answer sheet. One word or expression for each blank only. (0.5 point each, 12 points) . Programmers live in (1) fear of losing anyone's attention -anyone's. The (2) way to avoid doing so is to (3) everything brief, not to (4) the attention of anyone but instead to provide constant (5) through variety, novelty, action and (6). .But before he ever begins to write he will have (7) an emotional attitude from which he will never completely (8). It is his job, no doubt, to (9) his temperament and (10) getting stuck at some (11) stage, or in some (12) mood. .His car needs mechanics, and mechanics grow more expensive and less (13). The gadgets in the home are cheaper to (14) than repair. The more efficiently (15) the home seems to be, the more dependent it is on the great (16) corporations, as well as a diminishing army of servitors. Skills at the lowest level have to be (17) slavishly and exorbitantly (18). .It is only lately that I have (19) how much science of genetics is (20). Agronomists have taken to (21) all sorts of vegetables and fruits (22) their original nature. This sounds wonderful and often is insane. For the scientists have not as a rule (23) any interest whatsoever in the taste of the things they have (24) with! A.acquired B.avoid C.breeding D.changing E.constant F.discipline G.efficient H.escape I.found J.impersonal K.involved L.keep M.movement N.perverse O.premature P.replace Q.rewarded R.self-contained S.stimulation T.strain U.surest V.taken W.tempered X.wooed II. There are 15 sentences with a blank in each, followed by a list of words or expressions marked A to X. Choose the one that best completes each of the sentences and write the corresponding letter on your answer sheet. One word or expression for each blank only. (1 point each, 15 points) 25.In a hot summer day you would find the village children () in the small pond behind the woods. 26. I don't like the dishes in some Chinese restaurants abroad; for they () the local taste too much and the result is that the food is neither Chinese nor foreign. 27.Two pupils from the "Hope Schools" were () to represent Chinese children in the Euro 2000 ceremonies. 28. I think there is too much ( ) made by all people concerned, the parents, the media, and the authorities, about the university entrance examinations. 29. Suddenly the lights went out. She () in the dark for the matches. 30.He was very sad because he had tried very hard in the last three years but ()very little. 绍兴文理学院元培学院学年学期 英语专业____级《高级英语（上）》试卷（D） I. Matching (10%) Directions: Match the phrases in Column A with the appropriate Chinese explanations in Column B. Write down the letters with corresponding numbers on your ANSWER SHEET. Column A Column B 1 attribute to A 实行，实现，使生效 2 fall into B 一事无成，无进展 3 put … into effect C 恰当的例子 4 meddle in D 插手，干涉 5 pass for E 归因于 6 a case in point F 落入，陷入，分为 7 get nowhere G 误认为 8 in proper perspective H 强加于 9 let down I 用恰当的观点 10 impose on J 放下，降低，使失望 II. Paraphrase (20%) Directions: Explain in English the meaning of the underlined words or expressions in each of the following sentences and then write your answers on your ANSWER SHEET. 11. Unfortunately, acceptance, the imprecise response packing the least educational punch, gets the most equitable sex distribution in classrooms. 12. Classroom chivalry is not only misplaced; it is detrimental. 13. In a railroad accident a menagerie-tiger, whose cage had broken open, is said to have emerged, but presently crept back again. 14. A practical joker saw a discharged veteran carrying home his dinner. 15. The tiger is said to have emerged, but presently crept back again, as if too much bewildered by his new responsibilities. 16. The relationship is a formal and formalized one for which conventionalities suffice. 17. The construction of our vehicle presupposes a design. 18. This confident attitude, so essential to development of future speaking skill, is very fragile and can be stifled quite early. 19. The lion’s share of the damage is man’s doing. 20. I can guess that you are living on a devastated Earth. 21. Government is supposed to be the way we human beings handle our collective affairs, but we just can’t seem to get the hang of it. 22. As a model of lucid scrutiny of a life’s experience, Maugham’s The Summing-Up is unsurpassed. 23. I have never had to put wet towels round an aching brain in order to excavate the meanings from a poem of Tennyson. 24. Religious groups and those who elevate the status of poverty as they equate money with evil exhort us to live simply. 25. Some, on the other hand, determine to break out of their fettered status and relentlessly strive for their share of the gold. 26. Many fine business ideas go down the drain in this way. 27. They develop skills, become knowledgeable, develop expertise, and work very hard. 28. Jukes had been somewhat taken aback by the startling viciousness of the first squall. 29. Such is the prestige, the privilege, and the burden of command. 30. It unveiled the black figures of men caught on the bridge, heads forward, as if petrified in the act of butting. III. Reading Comprehension (30%) Directions: In this section there are four passages followed by a total of 15 multiple-choice questions. Read the passages carefully and then write your answers on your ANSWER SHEET. Passage One You may not have thought of it just this way, but the letter you write is part of you, and expression of your personality. Therefore to write letters that are mere patterns of form is to present a colorless personality. Letters, by their very nature, are too individual to be standardized. A letter may be absolutely perfect according to the standards of good taste and good form; but unless it also expresses something of the writer’s personality, it is not a good letter. In other words, don't be satisfied to write letters that are just correct and nothing more. Try to write letters that are correct for you... letters that are warm and alive with reflections of your own personality. And if this sounds like a platitude (陈词滥调), stop for a moment and think back over your recent correspondence. What was the most interesting letter you received? Was it a letter anyone could have written? Or was it a letter that instantly “came alive”as you read it—that brought the personality of the sender right into the room with you. 1. "如果，你只会在梦里与我相爱，请让我就此长眠。爱的梦，在见到你的那一刻成为现实。"-----G-Dragon 2.“从很久以前开始就有很强烈的想要获得自由的想法。我觉得它出现在我的音乐和fashion 中。我很感谢在我身边的人接受并且认为这是我的个性。但是想要的自由并不是盲目的。我是那种一旦只要决定了就一定要做的人。基本来说，自由不是我想要的全部。我想要认真的思考我为遥远未来所走的每一步。"---权志龙 3."我很早就知道有很多“Anti-G-Dragon”。但是我认为他们的批评和意见只会让我进步。"----------G-Dragon 4.至少在我看来，我永远不会停止歌唱。音乐，是我的命运，是我的终点。---G-Dragon of BigBang 【picnotmine】 5.“我想做那种，可以让人追梦，让人欣赏，让人享受，或者当他/她伤心的时候安慰疗伤的音乐。一种，可以让人记住的某一刻能想起的感同身受的音乐。”---权志龙，G-Dragon Fr BigBang 【PicSr: psycholicious】 6.我想要成为一名，能让成员们相信,信赖，依靠与跟随的Leader。---G-Dragon 【PicSr: psycholicious】 7.不断的大胆的尝试新的事物总是好的，而不是局限我们自己于某种特定的基因类型。- 但永远不要copy别人或者已经有的，勇敢的创造出属于自己的style。---------G-Dragon 【PicSr: psycholicious】 8."You just need to follow me. Oath. I will wait for you. " "你只需要跟随我。起誓。我会等你。”----- Captain G-Dragon. 9.“我喜欢有趣,喜欢恶作剧的女生,喜欢不可预知的,时时刻刻给你惊喜的人.如果我喜欢了这样的女生,我会紧紧拥抱她,永远不让她离开.【笑】如果我有女朋友了，我不希望她对其他人好。我只想让她把特别的撒娇可爱一面留给我.喜欢一个人,我想我会只为她展示我的某一面." G-Dragon【edit:psycholicious】 10.“一首拥有强烈信息的歌足以震撼整个世界。”“A song with strong message is strong enough to move the entire world.”—G-Dragon 【cr:psycholicious】 11.我认为我必须要很真诚的去写每一首歌。只有那样，听歌的人才能感受到我的感受或者是我要表达、传递的信息。只有那样，他们才能感受到自己的痛苦，并为之感动。----------G-Dragon 【PicSr: psycholicious】 12.【青春是摩托车!尽管大人说很危险不要,孩子们还是会骑,骑的飞快.青春亦如此.是想做就做,不让做也要的时期.如果超速就错过风景,盲目前进会经历挫折,如同现在的我.但未曾后悔.因为我还是相信自己是对的.想要继续危险的走下去,歌手好像不可以懂事.但会担心.现在会 Reading 1: This is Water 1. What’s the point of the fish story? The immediate point of the fish story is that the most obvious, ubiquitous, important realities are often the ones that are the hard est to see and talk about. 2. What is our natural default-setting, according to Wallace? Do you agree with him? If yes, give examples; if no, exampl es too, please. I am the absolute center of the universe, the real est, most vivid and important person in existence. Yes, I do. The worl d as you experience it is right there in front of you, or behind you, to the l eft or right of you, on your TV, or your monitor, or whatever. Other peopl e’s thoughts and feelings how to be communicated to you somehow, but your own are so immediate, urgent, real. 3. Is it possibl e for us to adjust our natural default-setting? If yes, how? And by the way, why should we adjust it? A: Yes, it is. We shoul d pay attention to what’s going on insid e me and stay alert and attentive instead of getting hypnotized by the constant monologue insid e your own head. what’s more, we shoul d l earn how to Think and how to d ecid e.The reason why shoul d we adjust it is that thinking in the way of d efault-setting that we experience the boring, frustrating, crowed parts of adult life. B: Yes, it is. Learning how to think------Learning how to exercise some control over how and what you think. It means being conscious and aware enough to choose what you pay attention to and to choose how you construct meaning from experience. If we d on’t adjust it, we will be total ly nosed. 4. What does it mean by ‘learn ing how to think’? And what is the justifiable way to think? Learning how to think really means l earning how to exercise some control over how and what you think. It means being conscious and aware enough to choose what you pay attention to and to choose how you construct meaning from experience. 5. What is the meaning of college education? Do you agree? If yes, further explains please, if no, define your meaning of college education and further illustrate it. Coll ege education is that it enabl es my tend ency to over-intell ectualize stuff, to get l ost in abstract argument insid e our head instead of simply paying attention to what’s going on right in front of us. 单元综合测试一 （L10）（上）P142 Some men drew the first slip which touched their fingers; others seemed to suspect that fate was trying to force on them a particular slip and when they bad drawn one a little way from the shoe would let it drop again and choose another. Time passed with incredible slowness, and the man called Voisin sat against the wall with the unlighted cigarette in his mouth paying them no attention at all. 有些人抽自己手指头碰到的第一个纸了。另一些人似乎怀疑是命运在试图强迫他们抽某一特定的纸条，因此当他们刚把一个纸条从鞋里抽出一点，又扔回去，再选另一张。时间过得令人难以置信地缓慢。叫瓦赞的那个人背靠着墙坐着，嘴上叼着未点燃的烟，丝毫没注意他人。 （L11）（上）P159 I imagined the picture on the wall without difficulty, and gave it a few deft touches, but this set me thinking of pictures in general, and then I remembered an art exhibition I had attended with my friend T. and what he said, and what I said, and I wondered how T. was faring these days, and whether his son was still at school. And so it went on, until I found myself meditating on cheese, or spiritualism, or the Rocky Mountains—but no sleep! 我想象挂在墙上的画倒是没有问题，然后我熟练地去扶正它。这会使我想到通常见到的画，然后我想起一个艺术展，那是和我的朋友T一起去的。我记得他说过什么话，然后我又说了什么话，然后我开始想T这一段时间会怎么样了，他的儿子是否还在念书。就这样继续下去，直到我不知不觉地想到奶酪或是唯灵论，或者落基山脉——就是睡不着！ （L6）（上）P76 When she saw that I didn’t like her reference to “people like you”, she stopped for a moment and then put he r hand on my arm. “Listen,” she said, “Magpie is happy new, finally. He is in good spirits, handsome and free and strong. He sits at the drum and sings with his brothers: he’s okay now. When he was saying all those things against the government and against the council, he became more and more ugly and embittered and I used to be afraid for him. But I’m not now. Please, why don’t you just leave it alone now?” 当她发现我不喜欢她提到“像你这样的人”时，她停了一下，然后把手放到我的胳膊上，说：“听我说，现在喜鹊终于高兴起来了。他情绪很好，很英俊、很自由、也很健壮。他和兄弟们一起坐在皮鼓前唱歌，他现在很正常。他总是说那些反对政府．反对印第安人事务委员会的话，说那些话时他就变得越来越可怕，越来越恼怒。我过去常因此而为他担忧，可是我现在不那样了。哦，我们还是顺其自然吧。” （L9）（上）P 124 The viewer is on a perpetual guided tour: 30 t the museum, 30 at the cathedral, 30 for a drink, then back on the bus to the next attraction—-except on television., typically, the spans allotted arc on the order of minutes or seconds, and the chosen delights are more often car crashes and people killing one another. In short, a lot of television usurps one of the most precious of all human gifts, the ability to focus your attention yourself, rather than just passively surrender it. 观众被领着进行无限期的游览：30分钟看博物馆，30分钟看大教堂，30分钟喝饮料，然后又回到车上，到下一个参观点。但是电视的时间是按分秒来计算的，而且所选的欣赏内 TODAY ??????????????我今天也若无其事地说 na o le do a mu la chi an gei ei gi la chio ?????????????????说没有女朋友偷偷把电话关掉 yo jia qin gu o da gu ma la nio mu lie cha ha gei ge go ??????????????????????今夜好想得到你的安慰别再问下去了 i pa meng no ei gei v lo an go si po to i ca eng mu chi ma la cho ?????????????????千万别让她听见了要守住秘密 ke nei ei gei cho dei lo te li chi an gei pi lo ha go Yeah ??????从我第一眼见到你no more Yeah nu cha mun su dan no more ??????????其他一切都看不上眼 a mu ga do po i zi a na go ??????????????我今天也假装没有女朋友 nei yo jia go o le ma nen o da ka ca ha go ?????????是什么吸引了我 mu a si na go ho li go ya ???????????‘这样可不行’‘我知道，这是外遇’ i lo an duei a la wei du i go ya Enjoy ???? ???????‘享受吗?你在说什麼' Enjoy i go ya mu si so i go ya ??????????你的样子告诉我是那样’ ke niang ke lo kei man po i go ya So today, I don’t care. Cuz we wild we rolling stones. /k?z/ /waild/ Today ?????????我像风般自由 Today na pa lang cho lo ca v lo gei I’m rockin’ my life away ??????????????我今天依旧说我很孤独这样你才会交出你的心na o le do wei lo do mio i nei me men chu chio ?????????????????不想独自一人留下余温依偎着 ho cha i ne gei she da ke nan yo wu le nan go ki dei go ????????????????????说和情人分手后遇见了你 sa lang ha ne sa lang gua hei o chi go sei lo eng ma na meng no la go ????????????????????等待着我的那个她入睡了吗na le ki da li go i neng nei ke nio neng cho i neng go i si ga yo ??????????外面凌晨的天空一片漆黑 pa ga sei bio ha ne leng ka ka mei 全国2010年10月高等教育自学考试 高级英语试题 课程代码：00600 I. The following paragraphs are taken from the textbooks, followed by a list of words or expressions marked A to Y. Choose the one that best completes each of the sentences and write the corresponding letter on your Answer Sheet. One word or expression for each blank only. (25 points, 1 point for each) Today’s heroes—some of them, anyway—tell us they enjoy their 1 . “And I 2 to myself at the men and the ladies. Who never 3 of us billion-dollar babies.” The 4 “culture hero” who 5 that is Alice Cooper. If I said that being black is a greater 6 than being a woman, probably no one would 7 me. Why? Because “we all know” there is 8 against black people in America. That there is prejudice against women is an idea that still 9 nearly all men—and, I am afraid, most women—as 10 . There is, however, another 11 possessed by the best work, which is even more important as a 12 of happiness than is the exercise of 13 . This is the element of constructiveness. In some work, though by no 14 in most, something is built up which remains as a 15 when the work is completed. My own state of mind, when I left Watts eight years ago to take up the 16 year at Whittier College, was 17 . It was to me less of a 18 ; it was the stepping off point of an Odyssey that was to take me through Whittier College and Oxford University, to Y ale Law School, and back to Watts. I had 19 then, as now, to make Watts my 20 . Well, it’s a good life and a good 21 , all said and 22 , if you don’t23 , and if you know that the big wide world hasn’t 24 from you yet, no, not by a long way, though it won’t be long now. The float bobbed more violently than II. Each of the following sentences is given four choices of words or expressions. Choose the right one to complete the sentence and write the corresponding letter on your Answer Sheet. (15 points, 1 point for each) 26. The citizens are grateful to the government for the ______ environment. A. wholesome B. wholesale C. noisome D. tiresome全国2013年10月高等教育自学考试高级英语试题
GDwho you音译歌词
全国高级英语试题及答案
高级英语(上)试卷D试题含答案
权志龙语录
高级英语阅读考试题目及答案完整版模板
《高级英语》试题册模拟试卷第一部分译文及答案讲解
TODAY 权志龙 中韩文 音译 歌词
2010年10月高级英语试题
相关主题
文本预览