Star-forming galaxies in low-redshift clusters: data and integrated galaxy properties^*

¹ Astrophysics Research Institute, Liverpool John Moores University, Birkenhead CH41 1LD, UK e-mail: cft@astro.livjm.ac.uk
² Royal Observatory, Greenwich, London SE10 9NF, UK
³ Institute of Astronomy, Madingley Road, Cambridge CB3 0HA, UK
⁴ School of Physics and Astronomy, The University of Nottingham, University Park, Nottingham NG7 2RD, UK
⁵ Department of Astronomy, University of Virginia, Charlottesville, VA 22903, USA

Received: 7 October 2007
Accepted: 23 April 2008

Abstract

Aims. This paper is a continuation of an ongoing study of the evolutionary processes affecting cluster galaxies.

Methods. Both CCD R band and Hα narrow-band imaging was used to determine photometric parameters (m_r, r₂₄, Hα flux, and equivalent width) and derive star formation rates for 227 CGCG galaxies in 8 low-redshift clusters. The galaxy sample is a subset of CGCG galaxies in an objective prism survey (OPS) of cluster galaxies for Hα emission.

Results. It is found that detection of emission-line galaxies in the OPS is 85%, 70%, and 50% complete at the mean surface brightness values of 1.25 10^-19, 5.19 10^-20, and 1.76 10^-20 W m^-2 arcsec^-2, respectively, measured within the R band isophote of 24 mag arcsec^-2 for the galaxy.

Conclusions. The CCD data, together with matched data from a recent Hα galaxy survey of UGC galaxies within v ≤ 3000 km s^-1, will be used for a comparative study of R band and Hα surface photometry between cluster and field spirals.