- E+A galaxies represent an important niche in galaxy evolution as a subset of post-starburst galaxies. Set apart from other post-starburst galaxies by their rapid quenching of star formation, E+As are thought to have started their formation outside a galaxy cluster's center and have fallen inward due to gravity; the star forming gas is ram-pressure stripped from the galaxy, quenching star formation and leaving behind a post-starburst galaxy. This galaxy has a high population of older, redder stars from the pre-starburst galaxy, and also contains new, blue, A-type stars that formed during the merger. This paper investigates E+As within the Hercules supercluster, and pays particular attention to Khutulun (SDSS 2MASX J16015198+1547326), a perfect example of a barred spiral (SBb type) E+A galaxy, and the inspiration for investigating spiral E+As. Spiral E+As represent an even smaller subgroup of galaxies as they have retained their arms through starburst, and thus were most likely formed without a major galaxy merger. This research presents theories on how spiral E+As formed and supports current theories that E+As tend to be in low/medium density regions within clusters and provides evidence that perhaps the gas density region is correlated to how the galaxy underwent starburst.
- Key Words: galaxies, evolution, post-starburst, E+A, spiral E+A, Hercules