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General study of group membership. II - Determination of nearby groups
We present a whole sky catalog of nearby groups of galaxies taken fromthe Lyon-Meudon Extragalactic Database. From the 78,000 objects in thedatabase, we extracted a sample of 6392 galaxies, complete up to thelimiting apparent magnitude B0 = 14.0. Moreover, in order to considersolely the galaxies of the local universe, all the selected galaxieshave a known recession velocity smaller than 5500 km/s. Two methods wereused in group construction: a Huchra-Geller (1982) derived percolationmethod and a Tully (1980) derived hierarchical method. Each method gaveus one catalog. These were then compared and synthesized to obtain asingle catalog containing the most reliable groups. There are 485 groupsof a least three members in the final catalog.
| Population studies in groups and clusters of galaxies. III - A catalog of galaxies in five nearby groups
Five nearby groups of galaxies have been surveyed using large-scaleplates from the 2.5 m duPont Telescope at Las Campanas Observatory.Catalogs of galaxies brighter than B(T) = 20 are presented for the Leo,Dorado, NGC 1400, NGC 5044, and Antlia groups. A total of 1044 galaxiesare included, from visual inspection of 14 plates, covering 31 degsquare. Galaxies have been classified in the extended Hubble system, andgroup memberships have been assigned based on velocity (where available)and morphology. About half the galaxies listed are likely members of oneof the nearby groups. The catalogs are complete to B(T) = 18, althoughthe completeness limits vary slightly from group to group. Based on Kingmodel fits to the surface density profiles, the core radii of the groupsrange from 0.3 to 1 Mpc, and central densities range from 120 to 1900galaxies Mpc exp-3 brighter than M(BT) = -12.5. Dynamical analysisindicates that all of the groups are likely to be gravitationally bound.
| Southern Galaxy Catalogue.
Not Available
| The Antlia cluster of galaxies and its environment - The Hydra I-Centaurus supercluster
The small Antlia cluster of galaxies was investigated by measuring manyradial velocities for galaxies from the Lauberts catalog in the Antliaregion. Apart from the Antlia cluster itself, four more small groupswere identified. These five systems form a tiny but not bound Antliamini-supercluster. The mini-supercluster consists of small groups andclusters and of a dispersed component of field galaxies. The five galaxysystems are also part of the large Hydra I-Centaurus supercluster. Thislarge supercluster belongs now to the class of well observed ones. Ithas a chain-like filamentary structure. This supercluster seems to beconnected to the Local Supercluster via two very extended but very loosegroups. The total structure is the triangle-shaped Virgo-HydraI-Centaurus supercluster.
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