The "Virgo photometry catalogue”; a catalogue of 1180 galaxies in thedirection of the Virgo Cluster's core

Abstract

We present a new catalogue of galaxies in the direction of the Virgo Cluster's core: the Virgo Photometry Catalogue (VPC). This catalogue contains 1180 galaxies (including background objects) within a 23 square-degree area of the sky centred on and . The VPC galaxy sample comprises of non-stellar objects brighter than ; the completeness limits being for the northern half of the survey area and for the southern half. Independently-calibrated photographic surface photometry is presented for over 1000 galaxies in the U, BJ and RC bands. Parameters listed for catalogued galaxies include: equatorial coordinates, morphological types, surface-brightness profile parameters (which preserve the majority of the original surface photometry information), U, BJ & RC isophotal magnitudes, BJ and [transformed] B total magnitudes, and equal-area and total colours, apparent angular radii, ellipticities, position angles, heliocentric radial velocities and alternative designations. All total magnitudes and total colours are extrapolated according to a new system denoted t in order to distinguish it from the T system already in use. The VPC is based primarily on four (one U, two BJ and one RC) UK-Schmidt plates, all of which were digitised using the Royal Observatory Edinburgh's (ROE) COSMOS measuring machine. All magnitudes, colours and surface-brightness parameters are derived from numerical integrations of segmented plate-scan data, except for (in 109 cases) saturated or (in 51 cases) inextricably-merged images; our segmentation software being able to cope with the vast majority of image mergers.