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arXiv · 1909.01509

Group pre-processing versus cluster ram-pressure stripping: the case of ESO156-G029

Robert Dzudzar·Virginia Kilborn·Chandrashekar Murugeshan·Gerhardt Meurer·Sarah M. Sweet·Mary Putman
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Abstract

We report on observations of ESO156-G029, member of a galaxy group which is positioned at the virial radius of cluster Abell 3193. ESO156-G029 is located ~ 1.4 Mpc in projected distance from the brightest cluster galaxy NGC1500. We show that ESO156-G029 has disturbed gas kinematics and a highly asymmetric neutral hydrogen (HI) distribution, which are consequences of group pre-processing, and possibly of ram-pressure. Based on the current data we propose a scenario in which ESO156-G029 had a minor gas-rich merger in the past and now starts to experience ram-pressure. We infer that the galaxy will undergo rapid evolution once it gets closer to the cluster centre (less than 0.5 Mpc) where ram-pressure is strong enough to begin stripping the HI from the galaxy.

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Robert Dzudzar, Virginia Kilborn, Chandrashekar Murugeshan, Gerhardt Meurer, Sarah M. Sweet, Mary Putman. 2019-09-04. Group pre-processing versus cluster ram-pressure stripping: the case of ESO156-G029. https://doi.org/10.1093/mnrasl%2Fslz139

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