Title: Black-Hole-to-Halo Mass Relation From UNIONS Weak Lensing 

Speaker: Wentao Luo 

Abstract: This work, for the first time, direct constraints on the black-hole-to-halo-mass relation using weak gravitational lensing measurements. We construct type I and type II Active Galactic Nuclei (AGNs) samples from the Sloan Digital Sky Survey (SDSS), with a mean redshift of 0.4 0.1 for type I (type II) AGNs. This sample is cross-correlated with weak lensing shear from the Ultraviolet Near Infrared Northern Survey (UNIONS). We compute the excess surface mass density of the halos associated with  36,181 AGNs from  94,308,561 lensed galaxies and fit the halo mass in bins of black-hole mass. We find that more massive AGNs reside in more massive halos. We see no evidence of dependence on AGN type or redshift in the black-hole-to-halo-mass relationship when systematic errors in the measured black-hole masses are included. Our results are consistent with previous measurements for non-AGN galaxies. At a fixed black-hole mass, our weak-lensing halo masses are consistent with galaxy rotation curves, but significantly lower than galaxy clustering measurements. Finally, our results are broadly consistent with state-of-the-art hydro-dynamical cosmological simulations, providing a new constraint for black-hole masses in simulations. 

Bio: Wentao Luo, graduated from Graduate School of Chinese Academy of Sciences in 2012 and then joined Shanghai Astronomical Observatory as an assistant researcher. He join Carnegie Mellon University as a post-doc sponsored by China Scholarship Council between 2015 and 2016. From 2016 to 2021, he worked as post-doc at SJTU and IPMU. And in May 2021, he joined USTC as project researcher and then joined Deep Space Exploration Lab (DSEL) in July 2023. 

Time: 14:00-15:00, 3/July, Wednesday

Venue: Room 508 (large seminar room), Department of Astronomy