Contenuti
Immagini
Carica la tua immagine
DSS Images Other Images
Articoli relazionati
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.
| 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.
| Photometry of luminous spiral galaxies in the direction of the Great Attractor
This paper presents photoelectric multiaperture BVI magnitudes for ahomogeneous sample of luminous spirals in the direction of the GreatAttractor. The total magnitudes B(T) and the mean colors (B - V) and (B- I) were determined for each galaxy and analyzed. The (B - I) colorchanges linearly with csc b over the range 3-10 and has a slope of 0.071mag. The A super bB values calculated from B - I agrees wellwith the A super bB values derived following the precepts ofBurstein and Heiles (1978). The (B - I) super b values show a slope of0.47 with log R. The corrected absolute magnitudes M superb,i,zB of spirals show little variation with luminosityclasses I, I-II, and II and have a dispersion of 0.85 mag. The samplewith well determined luminosities exhibits a uniform distribution overlog v up to v about 10,000 km/s. There is an indication that aselection-bias favoring higher luminosity galaxies sets in for spiralgalaxies with v greater than 10,000 km/s. The spirals with v less than10,000 km/s place a limit of about 500 km/s on peculiar velocities in ornear the Great Attractor.
| Redshifts of luminous spiral galaxies in the direction of the Great Attractor
The spatial distribution of a homogeneous samples of luminous spirals inthe direction of the 'Great Attractor' is studied. New radial velocitiesand published data yield redshifts for 94 percent of the sample. Thepresent survey, which does not include the cores of the Hydra andCentaurus clusters, shows no evidence for a major excess of velocitiesat or near the redshift of the Great Attractor. Luminous spirals withredshifts in the range 2000-4000 km/s are mainly distributed in a smallnumber of groups or clumps, whereas the spirals with redshifts in therange 4000-7000 km/s mostly appear to exhibit a rather smooth spatialdistribution.
| 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.
| A survey of high-luminosity spirals in the direction of the great attractor
Luminosity-classification techniques have been used to study galaxies in33 SRC Schmidt fields centered on the position of 'The Great Attractor'.A catalog and finding charts are given for 191 spiral galaxies, whichare probably of DDO luminosity classes I, I-II, or II. Radial velocitiesof these objects should provide considerable insight into thethree-dimensional structure of this region of space. The surfacedistribution of galaxies in the survey area is seen to be stronglyaffected by Galactic absorption. It is therefore not clear if anysignificance should be attached to the observation that there is noobvious concentration of galaxies at, or near, the position of The GreatAttractor.
| A wide angle redshift survey of the Hydra-Centaurus region
Spectroscopic observations of 266 galaxies in the Hya-Cen region arereported. Redshift data obtained at 350-700 nm with dispersion 21 nm/mmusing the UNIT spectrograph and RPCS detector on the 1.9-m RadcliffeReflector telescope at SAO during March 1985, May 1986, and March 1987are presented in tables and graphs and briefly characterized. It isshown that the Hya supercluster is separated from the Cen superclusterby a large void at right ascension 11 h 40 min, declination -35 deg, andradial velocity 5200 km/sec; a bridge of galaxies at velocity about 3200km/sec connects the two superclusters.
| Southern Galaxy Catalogue.
Not Available
|
Sottometti un nuovo articolo
Link relazionati
Sottometti un nuovo link
Membro dei seguenti gruppi:
|
Osservazione e dati astrometrici
Cataloghi e designazioni:
|
