学术报告160期：The Star Formation Rate and Star Formation Efficiency of Quasar Host Galaxies at Low redshifts

主讲人 (Speaker): 

谢燕霞

主讲人单位 (Speaker's Institute): 

北京大学科维理天文与天体物理研究所

邀请人 (Invited by): 

汤柏添

时间 (Time): 

星期五, 2019/12/13 - 10:00 to 11:00

地点 (Location): 

珠海校区海滨红楼17栋107 (Rm 107, Red House 17)

摘要 (Abstract): 

The tight correlation between the mass of supermassive black holes and the stellar velocity dispersion of galaxy bulges has been well-established in local quiescent galaxies, triggering numerous studies on the coevolution between black holes and their host galaxies. However, the origin of this relation remains elusive. Measurement of the interstellar medium content and star formation rate in active galaxies provides valuable insight into how effectively the host galaxies build their mass. Employing a new star formation rate (SFR) calibration developed by Xie & Ho (2019) based on polycyclic aromatic hydrocarbon (PAH) emission, we quantify the SFRs for the hosts of a sample of low-redshift quasars, and, in combination with measurements of gas content estimated from dust, we investigate their star formation efficiencies. A significant fraction of quasar hosts lies above the galaxy main sequence, possessing high star formation efficiencies similar to those of starburst galaxies, although many of the hosts have not undergone major mergers. AGN feedback may promote instead of suppressing star formation in these systems. While PAH emission effectively traces star formation in most objects, we find evidence that they may be destroyed in the most powerful quasars.

主讲人简介 (Speaker's CV): 

2003-2010 学士与硕士研究生 天津师范大学 2011-2016 博士研究生 中国科学院上海天文台 2014-2016 博士研究生 美国密苏里大学 2016-现在 博士后 北京大学科维理天文与天体物理研究所