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Star Formation in Cluster Galaxies at 0.2<z<0.55

Mike. L. Balogh·Simon L. Morris·H. K. C. Yee·R. G. Carlberg·E. Ellingson
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Abstract

The rest frame equivalent width of the [OII]3727 emission line, W(OII), has been measured for cluster and field galaxies in the CNOC redshift survey of rich clusters at 0.2 10 A, as expected in a model of cluster formation in which star formation is truncated upon infall. Evidence of supressed star formation relative to the field is present in the whole cluster sample, out to 2 R_{200}, so the mechanism responsible for the differential evolution must be acting at a large distance from the cluster centre, and not just in the core. The mean star formation rate in the cluster galaxies with the strongest emission corresponds to an increase in the total stellar mass of less than about 4% if the star formation is due to a secondary burst lasting 0.1 Gyr.

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Mike. L. Balogh, Simon L. Morris, H. K. C. Yee, R. G. Carlberg, E. Ellingson. 1997-07-30. Star Formation in Cluster Galaxies at 0.2<z<0.55. https://doi.org/10.1086/310927

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