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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arXiv · astro-ph/9511050

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

Summary - By using the data from the ESO Nearby Abell Cluster Survey (ENACS), 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. 1995-11-13. The Kinematics of Emission-Line Galaxies in Clusters from ENACS. https://arxiv.org/abs/astro-ph/9511050

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