Refining the E+A Galaxy: A Spatially Resolved Spectrophotometric Sample of Nearby Post-starburst Systems in SDSS-IV MaNGA (MPL-5)

TL;DR

This paper constructs a spatially resolved spectrophotometric sample of 30 nearby post-starburst E+A galaxies from SDSS-IV MaNGA, enabling detailed study of galaxy quenching processes with well-defined criteria.

Contribution

It introduces a rigorous selection method for E+A galaxies using spatially resolved spectroscopy, refining the classification and understanding of post-starburst systems.

Findings

Sample of 30 E+A galaxies identified within the green valley.

Stringent criteria ensure a contamination-free, well-defined post-starburst sample.

Provides detailed characteristics and selection criteria for future studies.

Abstract

Post-starburst galaxies are crucial to disentangling the effect of star formation and quenching on galaxy demographics. They comprise, however, a heterogeneous population of objects, described in numerous ways. To obtain a well-defined and uncontaminated sample, we take advantage of spatially resolved spectroscopy to construct an unambiguous sample of E + A galaxies - post-starburst systems with no observed ongoing star formation. Using data from the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) Survey, in the fourth generation of the Sloan Digital Sky Survey (SDSS-IV), we have identified 30 E + A galaxies that lie within the green valley of color-stellar mass space. We first identified E + A candidates by their central, single-fiber spectra and (u-r) color from SDSS DR15, and then further required each galaxy to exhibit E + A properties throughout the entirety of the system to three effective radii. We describe our selection criteria in detail, note common pitfalls in E + A identification, and introduce the basic characteristics of the sample. We will use this E + A sample, which has been assembled with stringent criteria and thus re-establishes a well-defined subpopulation within the broader category of post-starburst galaxies, to study the evolution of galaxies and their stellar populations in the time just after star formation within them is fully quenched.