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arXiv · 1410.5395

Trends in Dwarf Early-Type Kinematics with Cluster-centric Radius Driven By Tidal Stirring

A. J. Benson·E. Toloba·L. Mayer·J. D. Simon·P. Guhathakurta
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Abstract

We model the dynamics of dwarf early-type galaxies in the Virgo cluster when subject to a variety of environmental processes. We focus on how these processes imprint trends in dynamical state (rotational vs. pressure support as measured by the $λ^*_{\rm Re/2}$ statistic) with projected distance from the cluster center, and compare these results to observational estimates. We find a large scatter in the gradient of $λ^*_{\rm Re/2}$ with projected radius. A statistical analysis shows that models with no environmental effects produce gradients as steep as those observed in none of the 100 cluster realizations we consider, while in a model incorporating tidal stirring by the cluster potential 34% of realizations produce gradients as steep as that observed. Our results suggest that tidal stirring may be the cause of the observed radial dependence of dwarf early-type dynamics in galaxy clusters.

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A. J. Benson, E. Toloba, L. Mayer, J. D. Simon, P. Guhathakurta. 2014-10-20. Trends in Dwarf Early-Type Kinematics with Cluster-centric Radius Driven By Tidal Stirring. https://doi.org/10.1088/0004-637x%2F799%2F2%2F171

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