Title: The galaxy–halo connection --- beyond halo mass and beyond two-point statistics 

Speaker: Kuan Wang 

Abstract: The statistical connection between galaxies and dark matter halos is pivotal in connecting cosmological observation to theory. The assumptions made in galaxy–halo connection models reflect our understanding of galaxy physics and impact cosmological analyses. In this talk, I will discuss statistical tools used to constrain the galaxy–halo connection, especially its beyond-halo mass component, the secondary galaxy bias. We find that count statistics complement the traditional two-point correlation function, and largely improve the constraints. I will present observational constraints on the galaxy–halo connection, obtained from SDSS DR7 with count statistics. We find strong evidence for secondary galaxy bias in some samples. I will also introduce a new computational method which allows fast forward modelling of count statistics, and new observational results from the DESI One Percent Survey based on this method. Finally, I will talk about the role of the cosmic web in the galaxy–halo connection, in the IllustrisTNG simulations.   

Bio: Dr. Kuan Wang is an LCTP Postdoctoral Fellow at the University of Michigan. Kuan is a data-oriented numerical cosmologist. Her main research interest is the large-scale structure of the Universe. Specifically, she studies the non-equilibrium evolution of dark matter halos in cosmological simulations, the galaxy–halo connection, and the cosmic web. Kuan acquired her PhD degree in Physics at the University of Pittsburgh in 2021 and her Bachelor's degree in Astronomy at the University of Science and Technology of China in 2015. She will move to the University of Texas at Austin as a HETDEX Cosmology Fellow this fall. 

Time: 15:30-16:30, 2/July, Tuesday 

Venue: Room 506 (large seminar room), Department of Astronomy