The Spatial Distribution of Poststarburst Signatures in E+A Galaxies

Abstract

We investigated the spatial extent of young stars in E+A galaxies, usingspatially resolved long-slit spectroscopy of three E+A galaxies selectedfrom the Sloan Digital Sky Survey. The targets were selected so thatthey showed no H{α} emission and strong H{δ} absorption (EW{\gt}7{Å}). In all three targets, strong Balmer absorption was observedacross the entire E+A galaxy. The absorption region in each galaxy issignificantly extended, even after removing the effect of thepoint-spread function (PSF). We succeeded in removing the PSF effectfrom the spatial profile of one of the targets and found that thepoststarburst region in the galaxy is as extended as the old population.Model comparisons indicate that the age of the young population of thesegalaxies does not vary with radius. This suggests that starburst andtruncation in E+A galaxies is a galaxy-wide phenomenon.