Title: Investigating the Link between the Growth of SMBHs and Their Host Galaxies with X-ray Surveys

Speaker: Dr. Qingling Ni (MPE)

Time: 10:00am, August 25, 2023

Location: 3-402, PMO Xianlin Campus

Abstract: X-ray surveys have been an effective way to study growing supermassive black holes (SMBHs). Utilizing X-ray survey fields that have extensive multiwavelength data coverage, we can probe how SMBH growth links with the properties of their host galaxies, which will ultimately help to investigate the physical mechanisms behind the potential coevolution of SMBHs and their hosts. In my talk, I will present the relation between SMBH growth and host-galaxy compactness (represented by the central surface-mass density) we found among star-forming galaxies, which is more significant than the relation between SMBH growth and stellar mass or star formation rate. I will also present how the growth of SMBHs varies with Dn4000 (which is closely related to the age of stellar populations) measured from spectra of their hosts. We found that when controlling for various other host-galaxy properties, AGN fraction and SMBH growth level are higher among younger galaxies at Dn4000 < 1.9, consistent with the expectation from the stellar mass loss fueling scenario. Among the oldest/most massive galaxies at low redshift, this trend is not present, which may be associated with additional fueling from hot halo gas and/or enhanced accretion capability.