以往邀请报告
以往邀请报告

位置: 首页 > 以往邀请报告 > 2018春季 > 正文

Constraining Planet Mass-Scale Objects in Extragalactic Galaxies and Immediate Environment around Supermassive Black Holes with Quasar Microlensing
主讲人 主持人
时间 2018-05-14 21:50:31 报告题目
首作者 People
职称 联系电话
邮箱 研究方向
主讲人简介 地点
办公室 研究院 美国俄克拉荷马大学
日期: 
2018/05/14        
People: 
PROF. Xinyu Dai
Institute: 
美国俄克拉荷马大学

Title: Constraining Planet Mass-Scale Objects in Extragalactic Galaxies and Immediate Environment around Supermassive Black Holes with Quasar Microlensing

Speaker: PROF. Xinyu Dai
Institute: 美国俄克拉荷马大学(OU)
Time: 2018.05.14(Monday) 10:00-12:00
Place: Physics Building 552, Haiyun Campus, Xiamen University
Abstract: Gravitational microlensing provides a unique probe to study the population of lens objects and the emission region of the innermost parts of quasar accretion disks. We show that the current X-ray observations of microlensing signatures of emission close to the innermost stable orbit are able to constrain the population of lens objects down to planet mass scales. In particular, we found a planet mass fraction to be larger than 0.0001 of the halo mass, which is equivalent to 2,000 unbound objects ranging from Moon to Jupiter mass, free floating between stars, per main sequence star in the lens galaxy of RXJ1131-1231. In addition, two microlensing effects can be used to constrain black hole spins and X-ray reflection regions for high redshift quasars. The first effect is the excess iron line equivalent widths of lensed quasars compared to normal AGN, and the second is the distribution of iron line peak energies of lensed quasars. A microlensing analysis of the iron line equivalent widths prefers high spin values and very steep iron line emissivity profiles for quasars at z~2. I will also discuss the prospect of these sciences in the era of the next generation of X-ray telescopes.