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Studies of the Centaurus cluster. I. A catalogue of galaxies in the central region of the Centaurus cluster
The central region of the Centaurus cluster was surveyed on a film copyof a high-resolution photographic plate taken with the 100-inch du PontLas Campanas telescope. From visual inspection of the film, a largenumber of cluster galaxy candidates were identified down to a limitingmagnitude of 21.5 in B. Between cluster members and background objectswere distinguished by applying morphological criteria established inprevious studies of the Virgo and Fornax clusters. Following themorphological classification of each member, the images of all 296cluster galaxies on a SRC deep-blue sky survey plate were digitized,processed and analysed with programs written in the image processingpackage MIDAS. Aperture photometry yielded growth curves and totalinstrumental magnitudes of the galaxies. The magnitudes were calibratedwith independent photometric data and subsequently transformed intostandard B-magnitudes. We further established a set of structureparameters for each cluster galaxy: effective surface brightness,effective radius, central exponential surface brightness, and scalelength. For the ellipticals we additionally determined the shapeparameters of the light profiles. The catalogue (CCC) is only availablein electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr(130.79.128.5) or via http://cdsweb.u-strasbg.fr/Abstract.html
| The supergalactic plane redshift survey
Redshift measurements, about 1000 of which are new, are presented for1314 galaxies in a survey toward the apex of the large-scale streamingflow for ellipticals. The velocity histogram shows that the excess ingalaxy number counts in this area is due to a substantial concentrationof galaxies with discrete peaks at V about 3000 km/s and V about 4500km/s. After correction for the sampling function, the centroid of thedensity distribution is found to be near V about 4500 km/s.Normalization to the more extensive SSRS survey, which was selected bythe same criteria, shows that the region studied contains a considerableoverdensity of galaxies from 2000 to 6000 km/s. This result is in goodagreement with the 'great attractor' model suggested by Lynden-Bell etal. (1988) which attributes the peculiar motions of elliptical galaxiesover a large region of space to an extensive mass overdensity whichincludes the Hydra-Centaurus and Pavo-Indus superclusters. The centroidof the density enhancement is also consistent with new data by Dresslerand Faber (1990) of peculiar motions of elliptical and spiral galaxies,both of which show a zero crossing of the Hubble line at approximately4500-5000 km/s.
| Determination of the masses of elliptical galaxies and clusters of galaxies with AXAF
The procedures to be used in the determination of the mass and massdistribution of elliptical galaxies and clusters of galaxies, usingspatially resolved X-ray spectra of galaxies and clusters of galaxies tobe obtained by the imaging spectrometers on AXAF, are described. Theprocedures utilize the unique AXAF features of large band width, largefield of view, high angular resolution, long exposure times, and theavailability of sophisticated AXAF instrumentation. The techniquesdescribed involve the measurement of the surface brightness andtemperature profiles of the hot gas trapped in the potential wells ofthese systems. Then, by using the equation of hydrostatic equilibrium,which relates the total mass inside a given radius to the size, absolutetemperature, density gradient, and temperature profile, it will bepossible to infer the mass distribution in these objects to largephysical scales.
| Southern Galaxy Catalogue.
Not Available
| A catalog of morphological types in 55 rich clusters of galaxies
Data are presented from a study of 55 rich clusters of galaxies. Thedata include positions, morphological types, estimated total magnitudes,bulge sizes, and ellipticities for about 6000 galaxies, as determinedfrom high scale photographic plates. Data reduction procedures aredescribed, and a brief analysis of cluster richness, which indicatesthat Abell richness classes are only rough indicators of total clustermembership, is included.
| Corrections to the Reference Catalogue of Bright Galaxies (Third List)
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1972PASP...84..462C&db_key=AST
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