Title: Probing the dynamical and X-ray mass proxies of the cluster of galaxies Abell S1101 Show Chinese title

Title: 探测星系团阿贝尔S1101的动力学和X射线质量代理

Abstract: Context: The galaxy cluster Abell S1101 (S1101 hereafter) deviates significantly from the X-ray luminosity versus velocity dispersion relation (L-sigma) of galaxy clusters in our previous study. Given reliable X-ray luminosity measurement combining XMM-Newton and ROSAT, this could most likely be caused by the bias in the velocity dispersion due to interlopers and low member statistic in the previous sample of member galaxies, which was solely based on 20 galaxy redshifts drawn from the literature. Aims: We intend to increase the galaxy member statistic to perform a precision measurement of the velocity dispersion and dynamical mass of S1101. We aim for a detailed substructure and dynamical state characterization of this cluster, and a comparison of mass estimates derived from (i) the velocity dispersion (M_vir), (ii) the caustic mass computation (M_caustic), and (iii) mass proxies from X-ray observations and the Sunyaev-Zeldovich (SZ) effect. Methods: We carried out new optical spectroscopic observations of the galaxies in this cluster field with VIMOS, obtaining a sample of ~60 member galaxies for S1101. We revised the cluster redshift and velocity dispersion measurements based on this sample and also applied the Dressler-Shectman substructure test. Results: The completeness of cluster members within r200 was significantly improved for this cluster. Tests for dynamical substructure did not show evidence for major disturbances or merging activities in S1101. We find good agreement between the dynamical cluster mass measurements and X-ray mass estimates which confirms the relaxed state of the cluster displayed in the 2D substructure test. The SZ mass proxy is slightly higher than the other estimates. The updated measurement of the velocity dispersion erased the deviation of S1101 in the L-sigma relation. Show Chinese abstract

Abstract: 上下文：星系团Abell S1101（以下简称S1101）在我们之前的研究中明显偏离了星系团的X射线光度与速度弥散关系（L-sigma）。鉴于结合XMM-Newton和ROSAT的可靠X射线光度测量，这很可能是由于之前样本中由于背景天体和成员星系统计量不足导致的速度弥散偏差，而之前的样本仅基于文献中的20个星系红移。目标：我们旨在增加成员星系的统计量，以精确测量S1101的速度弥散和动力学质量。我们希望对这个星系团进行详细的子结构和动力学状态表征，并比较从以下三个方面得出的质量估计：(i) 速度弥散（M_vir），(ii) 激波质量计算（M_caustic），以及(iii) 来自X射线观测和Sunyaev-Zeldovich（SZ）效应的质量代理。方法：我们使用VIMOS对这个星系团区域的星系进行了新的光学光谱观测，获得了约60个成员星系的样本用于S1101。我们基于此样本重新测定了星系团的红移和速度弥散，并应用了Dressler-Shectman子结构测试。结果：该星系团在r200范围内的成员星系完整性显著提高。动力学子结构测试未显示S1101中有主要扰动或合并活动的证据。我们发现动力学星系团质量测量与X射线质量估计之间有良好的一致性，这证实了二维子结构测试中显示的星系团的平稳状态。SZ质量代理略高于其他估计值。更新后的速度弥散测量消除了S1101在L-sigma关系中的偏差。