A Catalog of Local E+A(post-starburst) Galaxies selected from the Sloan Digital Sky Survey Data Release 5

TL;DR

This paper presents a large, homogeneous catalog of 564 local E+A (post-starburst) galaxies from SDSS DR5, enabling detailed statistical and follow-up studies of this rare galaxy population.

Contribution

The authors compile and define a large, homogeneous catalog of 564 E+A galaxies using SDSS DR5, including Hα to improve selection accuracy and reduce contamination.

Findings

Catalog contains 564 E+A galaxies, one of the largest to date.

Inclusion of Hα reduces dusty star-forming galaxy contamination by up to 52%.

Provides a valuable resource for future statistical and observational studies.

Abstract

E+A galaxies have been interpreted as post-starburst galaxies based on the presence of strong Balmer absorption lines combined with the absence of major emission lines ([OII] nor H$\alpha$). As a population of galaxies in the midst of the transformation, E+A galaxies has been subject to an intense research activity. It has been, however, difficult to investigate E+A galaxies statistically since E+A galaxies are an extremely rare population of galaxies ($<$1% of all galaxies in the local Universe). Here, we present a large catalog of 564 E+A (post-starburst) galaxies carefully selected from half million spectra of the Sloan Digital Sky Survey Data Release 5. We define E+A galaxies as those with H$\delta$ equivalent width $>$5\AA and no detectable emission in [OII] $and$ H$\alpha$. The catalog contains 564 E+A galaxies, and thus, is one of the largest of the kind to date. In addition, we have included the H$\alpha$ line in the selection to remove dusty star-forming galaxies, which could have contaminated previous [OII]-based samples of E+A galaxies up to 52%. Thus, the catalog is one of the most homogeneous, let alone its size. The catalog presented here can be used for follow-up observations and statistical analyses of this rare population of galaxies.