MUSE-ALMA Haloes XIII: Kinematics and Stellar Properties of Tidal Features associated with Gas-rich Galaxies

Abstract Interactions between galaxies and their CGM can be observationally traced by extended tidal-like features. Interacting absorption-selected galaxies are galaxies that exhibit diffuse extended structures such as tidal features due to gravitational influence of other galaxies, and are associated with quasar absorbers. We report an analysis of 17 interacting galaxies associated with either H i or Mg ii absorbers and their tidal features at 0.1≲z≲ 0.6 selected from a total sample of 3658 galaxies. These were detected in HST and VLT MUSE observations and spectroscopically confirmed to be associated with strong intervening quasar absorbers. We estimated stellar masses (M*) of the tidal structures from spectral energy distribution fits and analyzed the kinematics of these structures using emission lines detected in the MUSE data. Our main findings are as follows: (1) Interacting absorbing galaxies exhibiting tidal features have enhanced star formation rates (SFR), specific star formation rates (sSFR), SFR surface densities, dust reddening, while exhibiting comparable emission metallicities to absorbing galaxies without tidal interactions. (2) The tidal features have higher sSFR but lower SFR and lower dust reddening than their host galaxies. (3) There is no significant difference in Mg ii λ 2796 rest-frame equivalent width between interacting and non-interacting absorbing galaxies. However, absorbing galaxies with tidal features are more massive and are located at greater distances from quasar sightlines, possibly tracing more extended CGM. Together, these results highlight the CGM’s influence traced by tidal features on the stellar and kinematic properties of the interacting absorbing galaxies.