Scaling laws in X-ray galaxy clusters at redshift between 0.4 and 1.3

被引:184
作者
Ettori, S
Tozzi, P
Borgani, S
Rosati, P
机构
[1] ESO, D-85748 Garching, Germany
[2] Osserv Astron Trieste, INAF, I-34131 Trieste, Italy
[3] Univ Trieste, Dipartimento Astron, I-34131 Trieste, Italy
[4] Ist Nazl Fis Nucl, Trieste, Italy
关键词
galaxies : cluster : general; galaxies : fundamental parameters; galaxies : intergalactic medium; X-ray : galaxies; cosmology : observations; cosmology : dark matter;
D O I
10.1051/0004-6361:20034119
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We present a study of the integrated physical properties of a sample of 28 X-ray galaxy clusters observed with Chandra at a redshift between 0.4 and 1.3. In particular, we have twelve objects in the redshift range 0.4-0.6, five between 0.6 and 0.8, seven between 0.8 and I and four at z > 1.0, compounding the largest sample available for such a study. We focus particularly on the properties and evolution of the X-ray scaling laws. We fit both a single and a double beta-model with the former which provides a good representation of the observed surface brightness profiles, indicating that these clusters do not show any significant excess in their central brightness. By using the best-fit parameters of the beta-model together with the measured emission-weighted temperature (in the range 3-11 keV), we recover gas luminosity, gas mass and total gravitating mass out to R-500. We observe scaling relations steeper than expected from the self-similar model by a significant (>3sigma) amount in the L-T and M-gas-T relations and by a marginal value in the M-tot-T and L-M-tot relations. The degree of evolution of the M-gas-T relation is found to be consistent with the expectation based on the hydrostatic equilibrium for gas within virialized dark matter halos. We detect hints of negative evolution in the L-T, M-gas-T and L-M-tot relations, thus suggesting that systems at higher redshift have lower X-ray luminosity and gas mass for fixed temperature. In particular, when the 16 clusters at z > 0.6 are considered, the evolution becomes more evident and its power-law modelization is a statistically good description of the data. In this subsample, we also find significant evidence for positive evolution, such as (1 + z)(0.3), in the E-z(4/3) S-T relation, where the entropy S is defined as T/n(gas)(2/3) and is measured at 0.1 R-200. Such results point toward a scenario in which a relatively lower gas density is present in high-redshift objects, thus implying a suppressed X-ray emission, a smaller amount of gas mass and a higher entropy level. This represents a non-trivial constraint for models aiming at explaining the thermal history of the intra-cluster medium out to the highest redshift reached so far.
引用
收藏
页码:13 / 27
页数:15
相关论文
共 84 条
[1]   Chandra observations of RX J1347.5-1145:: the distribution of mass in the most X-ray-luminous galaxy cluster known [J].
Allen, SW ;
Schmidt, RW ;
Fabian, AC .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2002, 335 (02) :256-266
[2]   The impact of cooling flows on the TX-LBol relation for the most luminous clusters [J].
Allen, SW ;
Fabian, AC .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 1998, 297 (03) :L57-L62
[3]   The X-ray virial relations for relaxed lensing clusters observed with Chandra [J].
Allen, SW ;
Schmidt, RW ;
Fabian, AC .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2001, 328 (03) :L37-L41
[4]   Chandra measurements of the distribution of mass in the luminous lensing cluster Abell 2390 [J].
Allen, SW ;
Ettori, S ;
Fabian, AC .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2001, 324 (04) :877-890
[5]   Chandra X-ray observations of the 3C 295 cluster core [J].
Allen, SW ;
Taylor, GB ;
Nulsen, PEJ ;
Johnstone, RM ;
David, LP ;
Ettori, S ;
Fabian, AC ;
Forman, W ;
Jones, C ;
McNamara, B .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2001, 324 (04) :842-858
[6]   ABUNDANCES OF THE ELEMENTS - METEORITIC AND SOLAR [J].
ANDERS, E ;
GREVESSE, N .
GEOCHIMICA ET COSMOCHIMICA ACTA, 1989, 53 (01) :197-214
[7]  
Arnaud KA, 1996, ASTR SOC P, V101, P17
[8]   The LX-T relation and intracluster gas fractions of X-ray clusters [J].
Arnaud, M ;
Evrard, AE .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 1999, 305 (03) :631-640
[9]   Physical implications of the X-ray properties of galaxy groups and clusters [J].
Babul, A ;
Balogh, ML ;
Lewis, GF ;
Poole, GB .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2002, 330 (02) :329-343
[10]  
BAUMGARTNER WH, 2003, IN PRESS APJ