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The ``Virgo photometry catalogue''; a catalogue of 1180 galaxies in the direction of the Virgo Cluster's core
We present a new catalogue of galaxies in the direction of the VirgoCluster's core: the Virgo Photometry Catalogue (VPC)*. This cataloguecontains 1180 galaxies (including background objects) within a 23square-degree area of the sky centred on R.A._{1950.0} = 12h 26m anddec._{1950.0} = 13(deg) 08'. The VPC galaxy sample comprises ofnon-stellar objects brighter than B_J25 = 19.0; thecompleteness limits being B_J25 ~18.5 for the northern halfof the survey area and B_J25 ~18.0 for the southern half.Independently-calibrated photographic surface photometry is presentedfor over 1000 galaxies in the U, B_J and R_C bands. Parameters listedfor catalogued galaxies include: equatorial coordinates, morphologicaltypes, surface-brightness profile parameters (which preserve themajority of the original surface photometry information), U, B_J &R_C isophotal magnitudes, B_J and [transformed] B total magnitudes,(U-B_J) and (B_J-R_C) equal-area and total colours, apparent angularradii, ellipticities, position angles, heliocentric radial velocitiesand alternative designations. All total magnitudes and total colours areextrapolated according to a new system denoted t in order to distinguishit from the T system already in use. The VPC is based primarily on four(one U, two B_J and one R_C) UK-Schmidt plates, all of which weredigitised using the Royal Observatory Edinburgh's (ROE) COSMOS measuringmachine. All magnitudes, colours and surface-brightness parameters arederived from numerical integrations of segmented plate-scan data, exceptfor (in 109 cases) saturated or (in 51 cases) inextricably-mergedimages; our segmentation software being able to cope with the vastmajority of image mergers. * Appendices B, C and E, which contain thesurface photometry, the main catalogue and the summary cataloguerespectively, are only available in electronic form. They can beobtained from La Centre des Donees astronomiques de Strasbourg (CDS) viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html.
| Studies of the Virgo Cluster. II - A catalog of 2096 galaxies in the Virgo Cluster area.
The present catalog of 2096 galaxies within an area of about 140 sq degapproximately centered on the Virgo cluster should be an essentiallycomplete listing of all certain and possible cluster members,independent of morphological type. Cluster membership is essentiallydecided by galaxy morphology; for giants and the rare class of highsurface brightness dwarfs, membership rests on velocity data. While 1277of the catalog entries are considered members of the Virgo cluster, 574are possible members and 245 appear to be background Zwicky galaxies.Major-to-minor axis ratios are given for all galaxies brighter than B(T)= 18, as well as for many fainter ones.
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