The spatial distribution of poststarburst signatures in E+A galaxies

We investigated the spatial extent of young stars in E+A galaxies, using spatially resolved long-slit spectroscopy of three E+A galaxies selected from the Sloan Digital Sky Survey. The targets were selected so that they showed no H sigma emission and strong H delta absorption (EW > 7 angstrom). In all three targets, strong Balmer absorption was observed across the entire E+A galaxy. The absorption region in each galaxy is significantly extended, even after removing the effect of the point-spread function (PSF). We succeeded in removing the PSF effect from the spatial profile of one of the targets and found that the poststarburst region in the galaxy is as extended as the old population. Model comparisons indicate that the age of the young population of these galaxies does not vary with radius. This suggests that starburst and truncation in E+A galaxies is a galaxy-wide phenomenon.