YuLing Chang
DESI Collaboration

Abstract
The circumgalactic medium (CGM), located at the interface of the large-scale galactic flows, holds key information about galaxy evolution, such as the quenching of massive galaxies by radio-mode feedback. This work aims to (1) study how massive galaxies and their CGM evolve and (2) explore how radio-mode feedback affects their CGM. To this end, we assemble a sample of 1 million luminous red galaxies (LRGs) with background QSOs using the largest spectroscopic dataset from the Dark Energy Spectroscopic Instrument (DESI) survey. We also crossmatch the galaxies with recent radio catalogs, constructing a sample of LRGs with radio emission and a corresponding control sample lacking radio detection. These extensive samples enable us to statistically characterize the properties of the CGM of DESI LRGs, including absorption line strengths, gas spatial distribution, and gas kinematics. In this talk, I will show the behaviors of gas around these massive galaxies, discuss the possible origin of this gas, and investigate the relationship between radio-mode feedback and the CGM. Our novel measurements can constrain the models of galaxy evolution, specifically in determining the influence of the feedback, and provide insight into the mechanisms governing the cosmic baryon cycle.

2024 July 17, 13:30

IA/U.Lisboa
Observatório Astronómico de Lisboa (Seminar room)
Tapada da Ajuda, 1349-018 Lisboa