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The Kinematics of Emission-Line Galaxies in Clusters from ENACS

A. Biviano·P. Katgert·A. Mazure·M. Moles·R. den Hartog·P. Focardi
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Abstract

By using the ENACS data, we have studied the properties of emission-line galaxies (ELG) in clusters. The fraction of ELG in clusters is 16~%; this fraction is slightly dependent on the cluster velocity dispersion, being larger for ``colder'' systems. ELG tend to occur more frequently than other cluster galaxies in substructures. However, only a minor cluster fraction has an ELG population with a mean velocity significantly different from that of the overall cluster population. The velocity distribution of cluster ELG is broader than that of the other cluster galaxies, which translates in a larger observed velocity dispersion. The velocity distribution for ELG in the inner cluster regions suggests that ELG are on mostly radial orbits.

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A. Biviano, P. Katgert, A. Mazure, M. Moles, R. den Hartog, P. Focardi. 1995-08-31. The Kinematics of Emission-Line Galaxies in Clusters from ENACS. https://arxiv.org/abs/astro-ph/9508149

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