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The 1000 Brightest HIPASS Galaxies: H I Properties
We present the HIPASS Bright Galaxy Catalog (BGC), which contains the1000 H I brightest galaxies in the southern sky as obtained from the H IParkes All-Sky Survey (HIPASS). The selection of the brightest sourcesis based on their H I peak flux density (Speak>~116 mJy)as measured from the spatially integrated HIPASS spectrum. The derived HI masses range from ~107 to 4×1010Msolar. While the BGC (z<0.03) is complete inSpeak, only a subset of ~500 sources can be consideredcomplete in integrated H I flux density (FHI>~25 Jy kms-1). The HIPASS BGC contains a total of 158 new redshifts.These belong to 91 new sources for which no optical or infraredcounterparts have previously been cataloged, an additional 51 galaxiesfor which no redshifts were previously known, and 16 galaxies for whichthe cataloged optical velocities disagree. Of the 91 newly cataloged BGCsources, only four are definite H I clouds: while three are likelyMagellanic debris with velocities around 400 km s-1, one is atidal cloud associated with the NGC 2442 galaxy group. The remaining 87new BGC sources, the majority of which lie in the zone of avoidance,appear to be galaxies. We identified optical counterparts to all but oneof the 30 new galaxies at Galactic latitudes |b|>10deg.Therefore, the BGC yields no evidence for a population of``free-floating'' intergalactic H I clouds without associated opticalcounterparts. HIPASS provides a clear view of the local large-scalestructure. The dominant features in the sky distribution of the BGC arethe Supergalactic Plane and the Local Void. In addition, one can clearlysee the Centaurus Wall, which connects via the Hydra and Antlia Clustersto the Puppis Filament. Some previously hardly noticable galaxy groupsstand out quite distinctly in the H I sky distribution. Several newstructures, including some not behind the Milky Way, are seen for thefirst time.
| A Catalog of H I-Selected Galaxies from the South Celestial Cap Region of Sky
The first deep catalog of the H I Parkes All Sky Survey (HIPASS) ispresented, covering the south celestial cap (SCC) region. The SCC areais ~2400 deg2 and covers δ<-62°. The average rmsnoise for the survey is 13 mJy beam-1. Five hundredthirty-six galaxies have been cataloged according to their neutralhydrogen content, including 114 galaxies that have no previous catalogedoptical counterpart. This is the largest sample of galaxies from a blindH I survey to date. Most galaxies in optically unobscured regions of skyhave a visible optical counterpart; however, there is a small populationof low-velocity H I clouds without visible optical counterparts whoseorigins and significance are unclear. The rms accuracy of the HIPASSpositions is found to be 1.9′. The H I mass range of galaxiesdetected is from ~106 to ~1011 Msolar.There are a large number of late-type spiral galaxies in the SCC sample(66%), compared with 30% for optically selected galaxies from the sameregion in the NASA Extragalactic Database. The average ratio of H I massto B luminosity of the sample increases according to optical type, from1.8 Msolar/Lsolar for early types to 3.2Msolar/Lsolar for late-type galaxies. The HI-detected galaxies tend to follow the large-scale structure traced bygalaxies found in optical surveys. From the number of galaxies detectedin this region of sky, we predict the full HIPASS catalog will contain~5000 galaxies, to a peak flux density limit of ~39 mJy (3 σ),although this may be a conservative estimate as two large voids arepresent in the region. The H I mass function for this catalog ispresented in a subsequent paper.
| Discovery of Numerous Dwarf Galaxies in the Two Nearest Groups of Galaxies.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1997AJ....114.1313C&db_key=AST
| A volume-limited sample of IRAS galaxies to 4000 km/s, 2: Neutral hydrogen observations from the Parkes telescope
We have extracted a volume-limited sample of spiral galaxies within 4000km/s from the Strauss et al. (1992) redshift survey of InfraredAstronomical Satellite (IRAS) galaxies. The purpose of the sample is touse distances obtained from the neutral hydrogen/near-infrared (I-band)Tully-Fisher relation to study deviations from uniform Hubble expansion.This will allow us to estimate the distribution of mass in the localuniverse and to place constraints on the value of the cosmologicaldensity parameter, omega 0. Here we report neutral hydrogen(H I) observations of 61 galaxies from this sample taken at the 64 mParkes telescope, 48 of which resulted in measured linewidth parameters.Empirical estimates of random and systematic errors in H I line widthsat low signal-to-noise ratio are described.
| Groups of galaxies within 80 Mpc. II - The catalogue of groups and group members
This paper gives a catalog of the groups and associations obtained bymeans of a revised hierarchical algorithm applied to a sample of 4143galaxies with diameters larger than 100 arcsec and redshifts smallerthan 6000 km/s. The 264 groups of galaxies obtained in this way (andwhich contain at least three sample galaxies) are listed, with the looseassociations surrounding them and the individual members of eachaggregate as well; moreover, the location of every entity among 13regions corresponding roughly to superclusters is specified. Finally,1729 galaxies belong to the groups, and 466 to the associations, i.e.,the total fraction of galaxies within the various aggregates amounts to53 percent.
| 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.
| Neutral hydrogen observations of southern galaxies
21-cm neutral hydrogen observations, made using the 64-m Parkes radiotelescope, are presented for 48 galaxies, 39 of which are cleardetections. The HI properties and homogeneous optical data, includingnew photometry, are tabulated for the galaxies. A high signal-to-noiseratio subset of these observations is used to demonstrate that theoverall flux-density scale is within a few per cent of northern (JodrellBank, and Green Bank) scales. HI-optical diameter correlations are shownto be a useful discriminant between competing diameter systems andindicate that the Lauberts ESO(B) catalogue is the most useful currentlyavailable source of southern galaxy diameters.
| Southern Galaxy Catalogue.
Not Available
| A catalogue of dwarf galaxies south of delta = -17.5 deg
A catalog of 584 suspected dwarf galaxies south of declination -17.5 degis presented. The survey was done on ESO(B) and SRC(J) plates and films.Position, major and minor axes, luminosity classes, and types(irregular, spiral, elliptical) are given.
| Oxygen abundances in low surface brightness galaxies
Oxygen abundances have been determined in H II regions in 12 low surfacebrightness galaxies. The dwarf irregulars conform with evolution asclosed systems, but the situation is less clear with the faint spirals.The importance of one gas rich, low luminosity barred spiral is pointedout.
| An optical and H I study of late-type low surface brightness galaxies
Neutral hydrogen and optical parameters are presented for 151 galaxiesof low surface brightness selected from UK Schmidt plates. The 21-cm H Iline was detected in 100 of these systems. It is found that the galaxiesshow the same trends of global properties with type as samples of brightgalaxies, while the data are consistent with the low surface brightness(LSB) galaxies being of systematically lower mass than bright galaxiesof the same type and linear dimensions. A constant value of hydrogenmass/(linear dimension)/squared is strongly suggested for LSB and brightgalaxies.
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