发稿时间:2021-09-13浏览次数:10

USTC Astronomy Colloquium Series: 2021 Fall
Probing the coevolution of black holes and galaxies utilizing X-ray surveys
Qingling Ni  博士
University of Edinburgh
2021/9/16, 4:00pm , the 19th-floor Observatory Hall
报告人:
Dr. Qingling Ni graduated from the Pennsylvania State University in 2021. She will start a postdoctoral position at the University of Edinburgh this fall. She is interested in utilizing extragalactic surveys to characterize AGN activity and the coevolution between black holes and galaxies.
摘要:
Recent studies show that a universal relation between black-hole (BH) growth and stellar mass (M*) or star formation rate (SFR) is an oversimplification of BH-galaxy coevolution, and that morphological and structural properties of host galaxies must also be considered. Particularly, a possible connection between BH growth and host-galaxy compactness was identified among starforming (SF) galaxies. Utilizing galaxies in the COSMOS field with Chandra coverage, we perform systematic partial-correlation analyses to investigate how sample-averaged BH accretion rate (BHAR) depends on host-galaxy compactness among SF galaxies, when controlling for M* or SFR. The projected central surface-mass density within 1 kpc, Σ1, is utilized to represent host-galaxy compactness in our study. We find that the BHAR-Σ1 relation is stronger than either the BHAR-M* or BHAR-SFR relation among SF galaxies. This BHAR-Σ1 relation among SF galaxies suggests a link between BH growth and the central gas density of host galaxies on the kpc scale, which may further imply a common origin of the gas in the vicinity of the BH and in the central ~kpc of the galaxy. This BHAR-Σ1 relation can also be interpreted as the relation between BH growth and the central velocity dispersion of host galaxies at a given gas content, indicating the role of the host-galaxy potential well in regulating accretion onto the BH. In this talk, I will also present the latest results from the XMM-SERVS survey, which is a ~50 ks depth XMM-Newton survey across ~13 deg^2. The XMM-SERVS survey provides a sample of ~10,000 AGNs that have extensive multiwavelength data coverage, enabling studies of BH growth in multidimensional space of galaxy parameters and across the full rang