报告题目：Method of detection of Dark Energy-Dark Matter interaction in Non-virialised clusters 

　　报告人： Morgan Le Delliou 博士（巴西圣保罗州立大学理论物理研究所博士后） 

　　时间安排：2016年9月9日（星期五）下午3：00        

　　地点：近代物理所5号楼1006会议室 

　　报告人简介： 

　　Morgan Le Delliou  博士，是巴西圣保罗州立大学理论物理研究所博士后， 1995年获得巴黎Xi—Orsay大学理论物理硕士；2002年获得加拿大Queen 大学理论物理博士学位。他主要从事暗物质晕结构和暗能量分析、非线性结构的成因. 主要工作发表在MNRAS, Astronomy and Astrophysics, JCAP, PLB, GRG, 和 PRD. 

　　报告内容摘要： 

　　the possibility of detection of Dark matter–Dark energy interaction. In particular, we try to detect the effects from such interaction in the balance of general clusters and for that purpose, we evaluate the departure from virial equilibrium of unbalanced clusters. We extend the use, from previous works, of the Layzer–Irvine equation for dynamical virial evolution of a simple model of interacting dark sector, with weak lensing and X-ray observations giving respectively the mass profiles and the intracluster gas temperatures. Selecting a set of clusters, we generate  measurements, through a Monte Carlo method, of observed virial ratios, interaction strength, rest virial ratio and departure from equilibrium factors. We found a compounded interaction strength for the set of clusters of $−1.61^+2.23_−16.34$, compatible with no interaction, but acompounded rest virial ratio of $−0.78 ± 0.13$, which would entail a 2σ detection. We confirm quantitatively that clusters of galaxies are out of equilibrium but further investigation is needed to constrain a possible interaction in the dark sector.