标题： ROSAT/HRI研究富光学的引力透镜星团CL0500-24 显示英文标题

标题： ROSAT/HRI study of the optically rich, lensing cluster CL0500-24

摘要： 本文介绍了对ROSAT/HRI观测到的光学丰富、引力透镜效应显著的星系团CL0500-24（或Abell S0506）的分析。 我们表明，这个被认为丰富的星系团在ROSAT波段的X射线亮度相对较低，为$1.1^{+0.2}_{-0.1}\times10^{44}$ erg/s，而全频带的X射线亮度为$2.0^{+1.5}_{-0.7}\times 10^{44}$ erg/s。 X射线辐射与红移为$z = 0.327$的星系团中的北部次浓度的星系有很强的相关性。 在1 Mpc范围内的（亚）团块的总质量为$(1.5\pm 0.8) \times 10^{14}$M$_\odot$，气体质量上限约为$0.5\times 10^{14}$M$_\odot$，对应的气体质量分数为$\le 30^{+30}_{-10}$%。 X射线亮度和扩展X射线发射的形态支持这样一个观点，即CL0500-24由两个速度相差$\Delta v \approx 3200$公里的星系团组成，它们恰好位于视线方向上。 显示英文摘要

摘要： An analysis of a ROSAT/HRI observation of the optically rich, gravitationally lensing galaxy cluster CL0500-24 (or Abell S0506) is presented. We show that the X-ray luminosity of this supposedly rich cluster is relatively low at $1.1^{+0.2}_{-0.1}\times10^{44}$ erg/s in the ROSAT band, the bolometric X-ray luminosity is $2.0^{+1.5}_{-0.7}\times 10^{44}$ erg/s. The X-ray emission is strongly correlated with the northern subconcentration of the cluster galaxies at redshift $z = 0.327$. The derived total mass of the (sub-)cluster within 1 Mpc is $(1.5\pm 0.8) \times 10^{14}$M$_\odot$, with an upper limit to the gas mass of about $0.5\times 10^{14}$M$_\odot$, corresponding to a gas mass fraction of $\le 30^{+30}_{-10}$\%. The X-ray luminosity and the morphology of the extended X-ray emission supports the view that CL0500-24 consists of two clusters at a velocity difference of $\Delta v \approx 3200$ km/s that happen to lie along the line of sight.