[1] Q. Huang and L. Fan, 2022 ApJS 262 39 Massive Early-type Galaxies in the HSC-SSP: Flux Fraction of Tidal Features and Merger Rates.

Tidal features in the outskirts of galaxies yield unique information about their past interactions and are a key prediction of the hierarchical structure formation paradigm (Martin+2022). Using novel methods and using new state-of-the-art data coming from the HSC-SSP survey, we investigated statistically for massive early type galaxies 1) the luminosity of tidal features, 2) the number of satellites, 3) the lifetime of tidal features. In addition, we provided analytic estimates of the merging rate of the sample galaxies. The results of this study shed light on the key questions of the mass assembly of massive galaxies and of the dynamics of tidal features.

[2] Q. Huang, J. Wang, et al. 2024 ApJ in press. WALLABY Pilot Survey: Star Formation Enhancement and Suppression in Gas-rich Galaxy Pairs

Interactions between galaxies significantly affect their star formation. Using the WALLABY data and a new 3D de-blending algorithm of astronomical data cubes, we study the SFR enhancement in galaxy pairs compared to normal galaxies of fixed stellar mass and HI mass. We find different behaviors in how the SFR changes with interaction strength in low-mass and high-mass galaxies. Tidal interactions and hydrodynamic effects act differently in interacting galaxies of different masses. Our results provide a coherent picture of gas-rich galaxy interactions and impose constraints on the underlying physical processes.