Dynamical masses of z~0.8 galaxies from LEGA-C

Within the half-light radius, Mdyn,eml is on average lower than M_dyn,*_, with a mean offset of -0.15+/-0.016dex and galaxy-to-galaxy scatter of 0.19dex, reflecting the combined random uncertainty. While data of higher spatial resolution are needed to understand this small offset, it supports the assumption that the galaxy-wide ionized gas kinematics do not predominantly originate from disruptive events such as star formation-driven outflows.

However, a similar agreement can be obtained without modeling from the integrated emission line dispersions for axis ratios q<0.8. This suggests that our current understanding of gas kinematics is not sufficient to efficiently apply asymmetric drift corrections to improve dynamical mass estimates compared with observations lacking the signal-to-noise ratio required for spatially extended dynamics.