Mid-Infrared Evidence for Accelerated Evolution in Compact Group Galaxies

Lisa May Walker; Kelsey E. Johnson; Sarah C. Gallagher; John E. Hibbard; Ann E. Hornschemeier; Jane C. Charlton; Thomas H. Jarrett

arXiv · 0908.2971

Mid-Infrared Evidence for Accelerated Evolution in Compact Group Galaxies

Lisa May Walker·Kelsey E. Johnson·Sarah C. Gallagher·John E. Hibbard·Ann E. Hornschemeier·Jane C. Charlton·Thomas H. Jarrett

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Abstract

We find evidence for accelerated evolution in compact group galaxies from the distribution in mid-infrared colorspace of 42 galaxies from 12 Hickson Compact Groups (HCGs) compared to the the distributions of several other samples including the LVL+SINGS galaxies, interacting galaxies, and galaxies from the Coma Cluster. We find that the HCG galaxies are not uniformly distributed in colorspace, as well as quantitative evidence for a gap. Galaxies in the infall region of the Coma cluster also exhibit a non-uniform distribution and a less well defined gap, which may reflect a similarity with the compact group environment. Neither the Coma Center or interacting samples show evidence of a gap, leading us to speculate that the gap is unique to the environment of high galaxy density where gas has not been fully processed or stripped.

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Lisa May Walker, Kelsey E. Johnson, Sarah C. Gallagher, John E. Hibbard, Ann E. Hornschemeier, Jane C. Charlton, Thomas H. Jarrett. 2009-08-20. Mid-Infrared Evidence for Accelerated Evolution in Compact Group Galaxies. https://arxiv.org/abs/0908.2971

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