A Deep, Wide-Field H-alpha Survey of Nearby Clusters of Galaxies

Abstract

We present a progress report on an ongoing H-alpha imaging survey of nearby clusters of galaxies. Four clusters have been surveyed to date: A1367, A1656, A347 and A569. A preliminary comparison of H-alpha luminosity functions obtained from our imaging survey with those from the prism survey reveals a significant level of incompleteness in the latter. This in turn is due to a combination of insensitivity to low-luminosity emission-line galaxies and to brighter galaxies with weak extended H-alpha emission. The survey has also revealed a unique population of clustered dwarf emission-line objects which may be the results of recent tidal encounters between larger gas-rich galaxies.