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Light and Motion in the Local Volume
Using high-quality data on 149 galaxies within 10 Mpc, I find nocorrelation between luminosity and peculiar velocity at all. There is nounequivocal sign on scales of 1-2 Mpc of the expected gravitationaleffect of the brightest galaxies, in particular infall toward groups, orof infall toward the supergalactic plane on any scale. Either darkmatter is not distributed in the same way as luminous matter in thisregion, or peculiar velocities are not due to fluctuations in mass. Thesensitivity of peculiar velocity studies to the background model ishighlighted.
| 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.
| Globular Clusters as Candidates for Gravitational Lenses to Explain Quasar-Galaxy Associations
We argue that globular clusters (GCs) are good candidates forgravitational lenses in explaining quasar-galaxy associations. Thecatalog of associations (Bukhmastova 2001) compiled from the LEDAcatalog of galaxies (Paturel 1997) and from the catalog of quasars(Veron-Cetty and Veron 1998) is used. Based on the new catalog, we showthat one might expect an increased number of GCs around irregulargalaxies of types 9 and 10 from the hypothesis that distant compactsources are gravitationally lensed by GCs in the halos of foregroundgalaxies. The King model is used to determine the central surfacedensities of 135 GCs in the Milky Way. The distribution of GCs incentral surface density was found to be lognormal.
| HI observations of nearby galaxies . I. The first list of the Karachentsev catalog
We present HI observations of the galaxies in the first list of theKarachentsev catalog of previously unknown nearby dwarf galaxies(Karachentseva & Karachentsev 1998). This survey covers all knownnearby galaxy groups within the Local Volume (i.e. within 10 Mpc) andtheir environment, that is about 25% of the total sky. A total of 257galaxies have been observed with a detection rate of 60%. We searched afrequency band corresponding to heliocentric radial velocities from -470km s-1 to ~ +4000 km s-1. Non-detections areeither due to limited coverage in radial velocity, confusion with LocalHI (mainly in the velocity range -140 km s-1 to +20 kms-1), or lack of sensitivity for very weak emission. 25% ofthe detected galaxies are located within the Local Volume. Thosegalaxies are dwarf galaxies judged by their optical linear diameter (1.4+/- 0.2 kpc on the average), their mean total HI mass (4.6107 Msun), and their observed linewidths (39 kms-1).
| HI observations of southern LSB dwarf galaxies from the Karachentsev catalogue
In this paper, we report on HI observations of newly detected nearbydwarf galaxies from the first part of the Karachentsev catalogue whichcontains low surface brightness galaxies spotted on the POSS II. Weperformed HI observations of 220 galaxies using the 100-m radiotelescope at Effelsberg, the Nancay radio telescope, and the AustraliaTelescope Compact Array. We discuss global parameters of the wholesample and the observations of the southern sample in more detail.Global parameters of the observed galaxies are as expected from thesample of nearby galaxies (Kraan-Korteweg and Tammann 1979). Theincrease of the number of known galaxies in the Local Volume (i.e.within a distance of 10 Mpc) could be as high as 20% for the whole sky.
| A Comparison of the Intrinsic Shapes of Two Different Types of Dwarf Galaxies: Blue Compact Dwarfs and Dwarf Ellipticals
We measure the apparent shapes for a sample of 62 blue compact dwarfgalaxies (BCDs) and compare them with the apparent shapes for a sampleof 80 dwarf elliptical galaxies (dEs). The BCDs are flatter, on average,than the dEs, but the difference is only marginally significant. We thenuse both nonparametric and parametric techniques to determine possibledistributions of intrinsic shapes for the BCDs. The hypothesis that BCDsare oblate spheroids can be ruled out with a high confidence level(>99%), but the hypothesis that they are prolate spheroids cannot beexcluded. The apparent shapes of BCDs are totally consistent with thehypothesis that they are triaxial ellipsoids. If the intrinsic axisratios beta and gamma are distributed according to a Gaussian with meansbeta 0 and gamma 0 and standard deviation sigma , we find that thebest-fitting distribution for BCDs has ( beta 0, gamma 0, sigma ) =(0.66, 0.55, 0.16), while that for dEs has ( beta 0, gamma 0, sigma ) =(0.85, 0.64, 0.24). Our results are consistent with the hypothesis thatBCDs have a close evolutionary relation with dEs.
| A list of new nearby dwarf galaxy candidates
To increase completeness of the distance limited sample of nearbygalaxies from the \cite[Kraan-Korteweg & Tammann (1979)]{Kra79}catalogue we undertook a search for small companions of larger knowngalaxies which have corrected radial velocities within 500 km/s. Basedprimarily on the POSS-II and ESO/SERC films we found 260 nearby dwarfgalaxy candidates with angular diameters aga0 .5 arcmin. More than 50%of the objects were revealed for the first time. As we suppose, asignificant part of them (about 30%) may really belong to the LocalVolume sample. Tables 1 and 2 also available in electronic form at CDSvia anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via\breakftp://cdsweb.u-strasbg.fr/Abstract.html
| Southern Sky Redshift Survey - The catalog
The catalog of radial velocities for galaxies which comprise thediameter-limited sample of the Southern Sky Redshift Survey ispresented. It consolidates the data of observations carried out at theLas Campanas Observatory, Observatorio Nacional, and South AfricanAstronomical Observatory. The criteria used for the sample selection aredescribed, as well as the observational procedures and the techniqueutilized to obtain the final radial velocities. The intercomparisonbetween radial velocity measurements from different telescopes indicatesthat the final data base is fairly homogeneous with a typical error ofabout 40 km/s. The sample is at present 90 percent complete, and themissing galaxies are predominantly objects with very low surfacebrightness for which it is very difficult to obtain optical redshifts.
| A catalog of southern groups of galaxies
A catalog of groups of galaxies identified in the southern Galactic capis presented. This catalog was constructed utilizing the group-findingalgorithm developed by Huchra and Geller (1982) to analyze galaxysamples with well-defined selection criteria and complete velocityinformation.
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