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Groups of Galaxies in the Two Micron All Sky Redshift Survey
We present the results of applying a percolation algorithm to theinitial release of the Two Micron All Sky Survey Extended SourceCatalog, using subsequently measured redshifts for almost all of thegalaxies with K<11.25 mag. This group catalog is based on the firstnear-IR all-sky flux-limited survey that is complete to|b|=5deg. We explore the dependence of the clustering on thelength and velocity scales involved. The paper describes a groupcatalog, complete to a limiting redshift of 104 kms-1, created by maximizing the number of groups containingthree or more members. A second catalog is also presented, created byrequiring a minimum density contrast of δρ/ρ>=80 toidentify groups. We identify known nearby clusters in the catalogs andcontrast the groups identified in the two catalogs. We examine andcompare the properties of the determined groups and verify that theresults are consistent with the UZC-SSRS2 and northern CfA redshiftsurvey group catalogs. The all-sky nature of the catalog will allow thedevelopment of a flow-field model based on the density field inferredfrom the estimated cluster masses.
| Nearby Optical Galaxies: Selection of the Sample and Identification of Groups
In this paper we describe the Nearby Optical Galaxy (NOG) sample, whichis a complete, distance-limited (cz<=6000 km s-1) andmagnitude-limited (B<=14) sample of ~7000 optical galaxies. Thesample covers 2/3 (8.27 sr) of the sky (|b|>20deg) andappears to have a good completeness in redshift (97%). We select thesample on the basis of homogenized corrected total blue magnitudes inorder to minimize systematic effects in galaxy sampling. We identify thegroups in this sample by means of both the hierarchical and thepercolation ``friends-of-friends'' methods. The resulting catalogs ofloose groups appear to be similar and are among the largest catalogs ofgroups currently available. Most of the NOG galaxies (~60%) are found tobe members of galaxy pairs (~580 pairs for a total of ~15% of objects)or groups with at least three members (~500 groups for a total of ~45%of objects). About 40% of galaxies are left ungrouped (field galaxies).We illustrate the main features of the NOG galaxy distribution. Comparedto previous optical and IRAS galaxy samples, the NOG provides a densersampling of the galaxy distribution in the nearby universe. Given itslarge sky coverage, the identification of groups, and its high-densitysampling, the NOG is suited to the analysis of the galaxy density fieldof the nearby universe, especially on small scales.
| The Catalog of Southern Ringed Galaxies
The Catalog of Southern Ringed Galaxies (CSRG) is a comprehensivecompilation of diameters, axis ratios, relative bar position angles, andmorphologies of inner and outer rings, pseudorings, and lenses in 3692galaxies south of declination -17 deg. The purpose of the catalog is toevaluate the idea that these ring phenomena are related to orbitalresonances with a bar or oval in galaxy potentials. The catalog is basedon visual inspection of most of the 606 fields of the Science ResearchCouncil (SRC) IIIa-J southern sky survey, with the ESO-B, ESO-R, andPalomar Sky surveys used as auxiliaries when needed for overexposed coreregions. The catalog is most complete for SRC fields 1-303 (mostly southof declination -42 deg). In addition to ringed galaxies, a list of 859mostly nonringed galaxies intended for comparison with other catalogs isprovided. Other findings from the CSRG that are not based on statisticsare the identification of intrinsic bar/ring misalignment; bars whichunderfill inner rings; dimpling of R'1pseudorings; pointy, rectangular, or hexagonal inner or outer ringshapes; a peculiar polar-ring-related system; and other extreme examplesof spiral structure and ring morphology.
| The surface photometry catalogue of the ESO-Uppsala galaxies
Not Available
| Southern Galaxy Catalogue.
Not Available
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