题目：Images and flares of geodesic hotspots around a Kerr black hole
报告人：郭敏勇 副教授 北京师范大学
时间：2024年6月20日（星期四）10:00
地点：虎溪校区理科楼LE201
邀请人：朱庆华
报告摘要：In this study, we develop a numerical method to generate images on an observer’s screen, formed by radiation from hotspots on any timelike orbits outside a black hole. This method uses the calculation of fractional numbers, enabling us not only to produce the overall image but also to distinguish between primary, secondary, and higher-order images. Building upon this, we compute the images of hotspots from eight potential types of geodesic timelike orbits outside a Kerr black hole, summarizing the properties of both the overall and individual order images. Furthermore, we calculate the centroid motion and lightcurve. Notably, we observe flare phenomena across all orbit types and classify these flares into three categories based on the Doppler and gravitational redshift effects.
报告人介绍：郭敏勇副教授，2014年本科毕业于北京科技大学，2019年博士毕业于北京师范大学，期间2017年至2019年在加拿大圆周理论物理研究所联合培养。2019年至2021年5月在北京大学高能中心做博士后。2021年5月至今在北京师范大学物理学系工作。目前从事黑洞图像、引力的全息性质等方面的研究。目前已发表研究论文40余篇，累计被引用1600余次。
