The Dependence of Dark Matter Halo Properties on the Morphology of Their Central Galaxies from Weak Lensing

Abstract

Xu & Jing reported a monotonic relationship between the host halo mass M _h and the morphology of massive central galaxies, characterized by the Sérsic index n , at fixed stellar mass, suggesting that morphology could serve as a good secondary proxy for the halo mass. Since their results were derived using the indirect abundance matching method, we further investigate the connection between the halo properties and central galaxy morphology using weak gravitational lensing. We apply galaxy–galaxy lensing to measure the excess surface density around CMASS central galaxies with stellar masses in the range of $11.3\lt \mathrm{log}{{M}}_{* }/{{M}}_{\odot }\lt 11.7$ , using the Hyper Suprime-Cam shear catalog processed through the Fourier_Quad pipeline. By dividing the sample based on n , we confirm a positive correlation between n and M _h , and observe possible evidence of the positive correlation of n and halo concentration. After accounting for color, we find that neither color nor morphology alone can determine the halo mass, suggesting that a combination of both may serve as a better secondary proxy. In comparison to hydrodynamic simulations, we find that TNG300 produces much weaker correlations between M _h and n . Furthermore, using SIMBA simulations with different feedback modes, we find that jet-mode active galactic nuclei feedback might be related to the relationship between the Sérsic index and halo mass.

Keywords

• Galaxy quenching
• Galaxy dark matter halos
• Galaxy structure