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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.
| Dynamics of clusters of galaxies with central dominant galaxies. I - Galaxy redshifts
Optical redshifts are presented for a sample of 638 galaxies in thefields of the clusters Abell 85, DC 0107-46, Abell 496, Abell 2052, andDC 1842-63. The velocity histograms and wedge diagrams show evidence fora foreground sheet of galaxies in Abell 85 and background sheets ofgalaxies in DC 0107-46 and Abell 2052. The foreground group projectedagainst the center of Abell 85 found by Beers et al. (1991) isconfirmed. No evidence of substructure was found in Abell 496, Abell2052, and DC 1842-63. The clusters have global velocity dispersionsranging from 551 km/s for DC 1842-63 to 714 km/s for A496, and flatdispersion profiles. Mass estimates using the virial theorem and theprojected mass method range from 2.3 x 10 exp 14 solar masses for DC0107-46 to 1.1 x 10 exp 15 solar masses for A85.
| Photometric properties of galaxies in the cluster DC 1842-63
Results are presented from photometric and kinematic observations of thecluster DC 1842-63, including total magnitudes for 174 galaxies, surfacephotometry and bulge-to-disk ratios for 31 galaxies, and redshiftsmeasurements for 20 galaxies. The mean cluster velocity is found to be4437 + or - 78 km/s with a cluster velocity dispersion of 507 km/s. TheX-ray luminosity of the cluster is shown to be 3.0 X 10 to the 43rderg/s in the 0.5 and 4.5 keV band.
| The group environment of Seyfert galaxies. II - Spectrophotometry of galaxies in groups
Medium-resolution spectrophotometric data of 104 galaxies have beenobtained. These galaxies are members of 22 loose groups of less thanabout 1 Mpc size. Thirteen of these groups contain Seyfert galaxies.This paper presents calibrated emission-line data and absolute opticalspectra of the individual galaxies as well as plates of each group.
| The group environment of Seyfert galaxies.
On Palomar and ESO Schmidt plates loose groups of 1 Mpc size areidentified. Spectroscopy of 15 such groups containing a Seyfert galaxyand 9 loose groups without a Seyfert galaxy comprising a total number of113 galaxies is presented. Using qualitative and absolute opticalspectroscopic criteria, the activity pattern in groups is described.Galaxies with strong emission-line activity are found in Seyfert groupsout to distances 300 kpc away from the Seyfert galaxy while innon-Seyfert groups such galaxies are virtually absent. The theoreticalimplications of these results with regard to the structural anddynamical conditions for tidally induced starburst and Seyfert activityare discussed.
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