Properties of gas clumps and gas clumping factor in the intra-cluster medium
Properties of gas clumps and gas clumping factor in the intra-cluster medium
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簇内介质中气体团簇的性质和气体团簇因子
DOI：
10.1093/mnras/sts375
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发表时间：
2013
影响因子：
4.8
通讯作者：
Ettori
中科院分区：
文献类型：
--
作者：
Eckert;Simionescu;Brüggen;Ettori
星系团内气体物质的空间分布并非完全平滑，但可能存在与子结构相关的气体团块。这些过密的气体亚结构通常是x射线观测对高密度气体的未解决偏差的来源，但它们明亮的光度峰值可能是星团内介质（ICM）内的解决源，深x射线暴露可能（已经）能够检测到。在本文中，我们的目标是研究这两个特征，使用一组高分辨率的宇宙学模拟。首先，我们监测了未解决的气体团块的偏差如何产生对全局团块参数的错误估计，并影响通过x射线观测对重子分数的测量。我们发现，基于窄径向带的x射线观测，很难将实际重子分数恢复到10 - 20%以上的不确定度。其次，我们研究了在邻近宇宙（z≤0.3）观测明亮x射线团块的可能性。我们对几种仪器（XMM,SuzakuandROSAT）进行了简单的模拟x射线观测，并提取了潜在可检测的明亮团块的统计数据。通过模拟预测的一些最亮的团块可能已经在大视场的x射线图像中被探测到。然而，它们的投影尺寸小，使得仅根据x射线形态难以证明它们的存在。研究发现，预热、活动星系核反馈和宇宙射线对气体团块的统计性质影响不大。
The spatial distribution of gas matter inside galaxy clusters is not completely smooth, but may host gas clumps associated with substructures. These overdense gas substructures are generally a source ofunresolvedbias of X-ray observations towards high-density gas, but their bright luminosity peaks may beresolvedsources within the intra cluster medium (ICM), that deep X-ray exposures may be (already) capable to detect. In this paper we aim at investigating both features, using a set of high-resolution cosmological simulations withenzo. First, we monitor how the bias by unresolved gas clumping may yield incorrect estimates of global cluster parameters and affects the measurements of baryon fractions by X-ray observations. We find that based on X-ray observations of narrow radial strips, it is difficult to recover the real baryon fraction to better than 10–20 per cent uncertainty. Secondly, we investigated the possibility of observing bright X-ray clumps in the nearby Universe (z≤ 0.3). We produced simple mock X-ray observations for several instruments (XMM,SuzakuandROSAT) and extracted the statistics of potentially detectable bright clumps. Some of the brightest clumps predicted by simulations may already have been already detected in X-ray images with a large field of view. However, their small projected size makes it difficult to prove their existence based on X-ray morphology only. Preheating, active galactic nuclei feedback and cosmic rays are found to have little impact on the statistical properties of gas clumps.
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DOI：
10.1111/j.1365-2966.2007.12241.x
发表时间：
2007-07
影响因子：
4.8
作者：
Elke Roediger;M. Brüggen
通讯作者：
Elke Roediger;M. Brüggen
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DOI：
--
发表时间：
2007
期刊：
影响因子：
--
作者：
J. Younger;G. Bryan
通讯作者：
G. Bryan
影响因子：
2.3
作者：
A. Hoshino;J. Henry;Kosuke Sato;Hiroki Akamatsu;Wataru Yokota;Shin Sasaki;Y. Ishisaki;T. Ohashi-T
通讯作者：
A. Hoshino;J. Henry;Kosuke Sato;Hiroki Akamatsu;Wataru Yokota;Shin Sasaki;Y. Ishisaki;T. Ohashi-T
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DOI：
--
发表时间：
2010
期刊：
影响因子：
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作者：
J. Burns;S. Skillman;B. O’Shea
通讯作者：
B. O’Shea
DOI：
10.1111/j.1365-2966.2009.15034.x
发表时间：
2008-08
影响因子：
4.8
作者：
K. Dolag;S. Borgani;S. Borgani;S. Borgani;G. Murante;V. Springel
通讯作者：
K. Dolag;S. Borgani;S. Borgani;S. Borgani;G. Murante;V. Springel