Subaru Weak Lensing Study of Seven Merging Clusters: Distributions of Mass and Baryons
Subaru Weak Lensing Study of Seven Merging Clusters: Distributions of Mass and Baryons
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DOI：
10.1093/pasj/60.2.345
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发表时间：
2007-02
影响因子：
2.3
通讯作者：
N. Okabe;Keiichi Umetsu Tohoku Univ.;Asiaa
中科院分区：
文献类型：
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作者：
N. Okabe;Keiichi Umetsu Tohoku Univ.;Asiaa
我们提出和比较投影分布的质量，星系，和团内介质（ICM）合并的星系团的样本的基础上联合弱透镜，光学光度，和X射线分析。我们的样本包括七个附近的阿贝尔集群，我们进行了系统的，深成像观测与斯巴鲁望远镜的Suprime-Cam。我们的七个目标集群，代表各种合并阶段和条件，使我们能够详细研究暗物质，ICM和星系之间的物理相互作用与集群的形成和演化。A1750和A1758是由两个星团组成的双星系统，A520，A754，A1758 N，A1758 S和A1914是正在进行的星团合并，A2034和A2142是冷锋星团。在双星星系团中，投影质量、可见光和X射线分布总体上相似且规则，没有明显的子结构。另一方面，正在进行的和冷锋合并的星系团揭示了高度不规则的质量分布。总的来说，质量分布似乎与星系光度分布相似，但它们的分布在许多方面与ICM分布有很大的不同。我们还测量了单个目标的全局集群参数，如集群质量，质光比，ICM温度。比较ICM和维里温度的合并集群从X射线和弱透镜分析，分别表明，ICM温度的进行中的冷锋集群是显着高于集群维里温度的一个因素的$\sim 2$。ICM中的这种温度过高可以用合并助推的效应来解释。
We present and compare projected distributions of mass, galaxies, and the intracluster medium (ICM) for a sample of merging clusters of galaxies based on the joint weak-lensing, optical photometric, and X-ray analysis. Our sample comprises seven nearby Abell clusters, for which we have conducted systematic, deep imaging observations with Suprime-Cam on Subaru telescope. Our seven target clusters, representing various merging stages and conditions, allow us to investigate in details the physical interplay between dark matter, ICM, and galaxies associated with cluster formation and evolution. A1750 and A1758 are binary systems consisting of two cluster-sized components, A520, A754, A1758N, A1758S, and A1914 are on-going cluster mergers, and A2034 and A2142 are cold-front clusters. In the binary clusters, the projected mass, optical light, and X-ray distributions are overall similar and regular without significant substructures. On-going and cold-front merging clusters, on the other hand, reveal highly irregular mass distributions. Overall the mass distribution appears to be similar to the galaxy luminosity distribution, whereas their distributions are quite different from the ICM distribution in a various ways. We also measured for individual targets the global cluster parameters such as the cluster mass,the mass-to-light ratio, and the ICM temperature. A comparison of the ICM and virial temperatures of merging clusters from X-ray and weak-lensing analyses, respectively, shows that the ICM temperature of on-going and cold-front clusters is significantly higher than the cluster virial temperature by a factor of $\sim 2$. This temperature excess in the ICM could be explained by the effects of merger boosts.