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JOINT ANALYSIS OF CLUSTER OBSERVATIONS. II. CHANDRA/XMM-NEWTON X-RAY AND WEAK LENSING SCALING RELATIONS FOR A SAMPLE OF 50 RICH CLUSTERS OF GALAXIES
被引:203
作者:
Mahdavi, Andisheh
[1
]
Hoekstra, Henk
[2
]
Babul, Arif
[3
]
Bildfell, Chris
[3
]
Jeltema, Tesla
[4
]
Henry, J. Patrick
[5
]
机构:
[1] San Francisco State Univ, Dept Phys & Astron, San Francisco, CA 94131 USA
[2] Leiden Univ, Leiden Observ, NL-2333 CA Leiden, Netherlands
[3] Univ Victoria, Dept Phys & Astron, Victoria, BC V8W 3P6, Canada
[4] UC Santa Cruz, Santa Cruz Inst Particle Phys, Santa Cruz, CA 95064 USA
[5] Univ Hawaii, Inst Astron, Honolulu, HI 96822 USA
基金:
美国国家科学基金会;
加拿大自然科学与工程研究理事会;
关键词:
galaxies: clusters: general;
galaxies: clusters: intracluster medium;
gravitational lensing: weak X-rays: galaxies: clusters;
SOUTH-POLE TELESCOPE;
LUMINOSITY-TEMPERATURE RELATION;
HUBBLE-SPACE-TELESCOPE;
SUNYAEV-ZELDOVICH;
XMM-NEWTON;
INTRACLUSTER MEDIUM;
COOLING FLOWS;
COSMOLOGICAL SIMULATIONS;
POWER SPECTRUM;
DATA REDUCTION;
D O I:
10.1088/0004-637X/767/2/116
中图分类号:
P1 [天文学];
学科分类号:
0704 ;
摘要:
We present a study of multiwavelength X-ray and weak lensing scaling relations for a sample of 50 clusters of galaxies. Our analysis combines Chandra and XMM-Newton data using an energy-dependent cross-calibration. After considering a number of scaling relations, we find that gas mass is the most robust estimator of weak lensing mass, yielding 15%+/- 6% intrinsic scatter at r(500)(WL) (the pseudo-pressure Y-X yields a consistent scatter of 22%+/- 5%). The scatter does not change when measured within a fixed physical radius of 1 Mpc. Clusters with small brightest cluster galaxy (BCG) to X-ray peak offsets constitute a very regular population whose members have the same gas mass fractions and whose even smaller (<10%) deviations from regularity can be ascribed to line of sight geometrical effects alone. Cool-core clusters, while a somewhat different population, also show the same (<10%) scatter in the gas mass-lensing mass relation. There is a good correlation and a hint of bimodality in the plane defined by BCG offset and central entropy (or central cooling time). The pseudo-pressure YX does not discriminate between the more relaxed and less relaxed populations, making it perhaps the more even-handed mass proxy for surveys. Overall, hydrostatic masses underestimate weak lensing masses by 10% on the average at r(500)(WL); but coolcore clusters are consistent with no bias, while non-cool-core clusters have a large and constant 15%-20% bias between r(2500)(WL) and r(500)(WL), in agreement with N-body simulations incorporating unthermalized gas. For non-cool-core clusters, the bias correlates well with BCG ellipticity. We also examine centroid shift variance and power ratios to quantify substructure; these quantities do not correlate with residuals in the scaling relations. Individual clusters have for the most part forgotten the source of their departures from self-similarity.
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页数:18
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