Deep inside the core of Abell 1795:: the Chandra view

被引:173
作者
Ettori, S
Fabian, AC
Allen, SW
Johnstone, RM
机构
[1] Univ Cambridge, Inst Astron, Cambridge CB3 0HA, England
[2] ESO, D-85748 Garching, Germany
关键词
galaxies : clusters : individual : A1795; dark matter; X-rays : galaxies;
D O I
10.1046/j.1365-8711.2002.05212.x
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We present X-ray spatial and spectral analysis of the Chandra data from the central 400 h(50)(-1) kpc of the cluster of galaxies Abell 1795. The plasma temperature rises outwards by a factor of 3, whereas the iron abundance decreases by a factor of 4. The spatial distribution of oxygen, neon, sulphur, silicon and iron shows that supernovae Type la dominate the metal enrichment process of the cluster plasma within the inner 150 kpc. Resolving both the gas density and temperature in nine radial bins, we recover the gravitational mass density profile and show that it flattens within 100 kpc as rho(DM) proportional to r(-0.6) with a power-law index flatter than -1 at >3sigma level. The observed motion of the central galaxy and the presence of excesses and deficits along the north-south direction in the brightness distribution indicate that the central cluster region is not relaxed. In the absence of any non-gravitational heating source, the data from the inner similar to200 kpc indicate the presence of a cooling flow with an integrated mass deposition rate of about 100 M-. yr(-1). Over the same cluster region, the observed rate of 74 M-. yr(-1) is consistent with the recent XMM-Newton Reflection Grating Spectrometer limit of 150 M-. yr(-1).
引用
收藏
页码:635 / 648
页数:14
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