Galactic Stellar Haloes in ΛCDM simulations
Event Timeslots (1)
Thursday 11th
-
Galactic Stellar Haloes in ΛCDM simulations
Using the cosmological hydrodynamic simulation TNG50-1 we characterize stellar haloes (SHs) of galaxies with stellar mass in the range 8.0 ≲ log M*/M☉ ≲ 11.0 in a ΛCDM Universe. Defined as the accreted stellar component of a galaxy, our SHs encompasses the stars born ex-situ that are bounded to the host galaxy at redshift z = 0, up to the virial radius. We analyze the stellar halo density profile from isolated central galaxies and their correlation with intrinsic properties of the host galaxy, like kinematics, age and accreted mass ratio. The logarithmic slope of density profile shows a large scatter ranging -12 ≲ α ≲ -3 and i) it does not correlate with the total stellar mass M* for dwarfs galaxies but systematically increases for normal galaxies; ii) is inversely proportional to the SH rotation; and iii) is proportional to the median stellar age of the SH. These results aim to predict and compare simulated and observed SHs properties for galaxies with mass lower than the Milky Way or Andromeda, suggesting that the analysis of outer regions of galaxies could be insightful to unveil intrinsic properties of stellar population and the assembly history of galaxies in a wide range of mass.