Reconstructing the Assembly of Massive Galaxies. III: Quiescent Galaxies Loose Angular Momentum as They Evolve in a Mass-dependent Fashion

Understand

We study the evolution of stellar kinematics of a sample of 952 massive quiescent galaxies with $M_*>10^{10.5}M_\odot$ at $0.6<z<1$.

• Utilizing spatially integrated spectroscopy from the LEGA-C survey, we focus on the relationship between the observed integrated stellar velocity dispersion ($\sigma^\prime_{star}$) and the morphological axial ratio ($q$), and its variation with the stellar age and mass of quiescent galaxies.
• For the youngest quiescent galaxies, regardless of stellar mass, $\sigma^\prime_{star}$ decreases with increasing $q$, a trend that is consistent with a system having significant rotation and hence suggests that massive galaxies still retain significant amount of angular momentum in the aftermath of quenching.
• As they continue to evolve, the variation of the $\sigma^\prime_{star}$-$q$ relationship depends on stellar mass.