2014/06/24 by Michael Pracy, M. S. Owers, Matt Owers +10
Physics and Astronomy · #Astronomy #Astronomy and Astrophysical Research #Astrophysics #Astrophysics and Star Formation Studies #Emission spectrum #Galaxies: Formation, Evolution, Phenomena #Galaxy #Luminous infrared galaxy #Physics #Spectral line #Spectroscopy #Star formation #Stellar population #astro-ph.GA
paper · pdf · doi:10.1093/mnras/stu1103
Accepted to MNRAS, 7 pages, 2 figures
arxiv created 2014/06/24 · openalex publication_date 2014/07/10 · arxiv updated 2015/06/22 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Approximately half of the nearby E+A galaxies followed up with 21-cm observations have detectable H i emission. The optical spectra of these galaxies show strong post-starburst stellar populations but no optical emission lines implying star formation is not ongoing despite the presence of significant gas reservoirs. We have obtained integral field spectroscopic follow-up observations of the two brightest, and nearest, of the six E+A galaxies with H i 21-cm emission in the recent sample of Zwaan et al. In the central regions of both galaxies, the observations are consistent with a post-starburst population with little emission. However, outside the central regions both galaxies have strong optical emission lines, with a clumpy or knot-like distribution, indicating ongoing star formation. We conclude that in these two cases, the presence of optical spectra lacking evidence for star formation while a large gas mass is present can be explained by an aperture effect in selecting the nearby E+A galaxies using single-fibre spectroscopy that probes only the galaxy core.