2020ApJ...905...79S

We present Gemini Multi-Object Spectrograph (GMOS) integral field unit (IFU) observations of six massive (M_* >= 10¹¹ M_☉) A-star dominated post-starburst galaxies at z ∼ 0.6. These galaxies are a subsample of the SQuIGG\vecLE Survey, which selects intermediate-redshift post-starbursts from the Sloan Digital Sky Survey spectroscopic sample (DR14) with spectral shapes that indicate they have recently shut off their primary epoch of star formation. Using Hδ_A absorption as a proxy for stellar age, we constrain five of the galaxies to have young (∼600 Myr) light-weighted ages at all radii and find that the sample on average has flat age gradients. We examine the spatial distribution of mass-weighted properties by fitting our profiles with a toy model including a young, centrally concentrated burst superimposed on an older, extended population. We find that galaxies with flat Hδ_A profiles are inconsistent with formation via a central secondary starburst. This implies that the mechanism responsible for shutting off this dominant episode of star formation must have done so uniformly throughout the galaxy.