Title：Moving corona and the relativistic broad iron emission line

Speaker: Prof. Ye-Fei Yuan (USTC)

Abstract：

 Iron fluorescence emission lines from X-ray binaries (XRBs) is an important diagnosis of the physical processes near the event horizon of black holes. In this work, we investigate the line profile of the relativistic broad iron lines from the cool accretion disk of black hole, due to the asymmetric illumination of a moving corona which moves away from the disk with a relativistic velocity. Both the off-axis location and the radial velocity of the moving corona are considered. Our results clearly show that the illumination and the line profile are dependent on the position and velocity of the corona, since the disk region below the corona receives more flux, which is the most important factor to affect the line profiles. As expected, if the corona is close to the receding part of the rotating disk, the red peak is enhanced while the blue peak is weaken in the broad line profile, and the central energy of the emission line is low. Whilst, if the corona is close to the approaching part of the disk, the blue peak is strong and the central energy of the emission line is high, even higher than the intrinsic energy of the emission line. Due to the beaming effect of the moving corona, the corona with the high velocity illuminates the outer region of the disk, which leads to the red peak disappears and there is only one blue peak in the profile of the emission line.

Research interests: relativistic astrophysics, focusing on compact objects (neutron stars, black holes and white dwarfs), and nuclear astrophysics (physics of dense nuclear matter, high energy neutrinos)

EDUCATION:

June, 1999: Ph. D. in astrophysics

Thesis: Radiation mechanisms and the interior structure of neutron stars in strong magnetic fields (Supervisor: Prof. J.L. Zhang)

Sep., 1993--Jan., 1999: Center for Astrophysics, USTC, Hefei, Ph.D. candidate

POSITIONS and VISITING:

Jun. 2006 - Dec. 2014: Department chair

Dec. 2005-- Professor, Center for Astrophysics, USTC

Nov. 2002--Aug. 2003: Visiting Scientist, Department of Astronomy, Harvard University

Jan. 2001-- Dec. 2005: Associate Professor, Center for Astrophysics, USTC

Jan. 1999--Jan. 2001: Lecturer, Center for Astrophysics, USTC

ASSOCIATIONS:

Chairman of Anhui Astronomical Society

The International Astronomical Union (IAU) membership

The executive member of the council of the Chinese Astronomical Society

报告题目：运动冕与相对论宽铁线

报告人：袁业飞（中国科学技术大学物理学院天文学系教授）

报告摘要：

来自X射线双星的铁荧光发射线研究黑洞视界附近物理过程的重要的探针。在本工作中，我们研究了受到偏轴的、以接近相对论速度运动的高温冕照射的冷吸积盘产生的相对论的宽铁线的轮廓。结果显示,冕的照明与最终的铁发射线轮廓敏感依赖于冕的位置和速度。靠近冕的一侧的吸积盘接收到更多的原初硬X射线。如果冕靠近吸积盘背离我们运动的的一侧，则红峰加强，蓝峰减弱，发射线的中心能量偏低；如果冕靠近吸积盘靠近朝向我们运动的一侧，则蓝峰加强，红峰减弱，发射线的中心能量变高，甚至高于线的内禀能量。由于相对论beaming效应，当冕的速度增高时，冕主要照射盘的外区，导致发射线可能只有一个蓝峰。

个人简历：1999年中国科学技术大学天体物理中心博士毕业并留校任教。2005年晋升为教授，曾任天文学系执行主任。2017年获国家杰出青年科学基金项目资助。主要从事黑洞天体物理领域的教学和科研工作。曾应邀访问美国哈佛大学、康奈尔大学等天文机构，并开展合作研究。目前担任中国天文学会常务理事。

Time:10:00-11:00AM, 23/Nov, Wednesday

Tencent Meeting link:  https://meeting.tencent.com/dm/z1HnOuAgiFPC

Meeting ID: 360-1536-1663

Password: 2022