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HI observations of nearby galaxies. IV. More dwarf galaxies in the southern sky
In this paper we present HI observations of nearby galaxies from twomore lists of the Karachentsev catalog of candidates for nearby dwarfgalaxies in the southern sky. Observations north of declination -31degrwere performed with the 100-m radio telescope at Effelsberg. Data formore southern galaxies were taken from HIPASS(www.atnf.csiro.au/research/multibeam). This sample is a supplement tothe list of 94 southern dwarf galaxy candidates (1998, A&AS, 127,409) located in the same declination range around the known Local Volumegalaxies (i.e. galaxies within 10 Mpc, LV hereafter). We observed 17galaxies not observed in the previous sample; and all 67 candidate dwarfgalaxies from the SERC EJ sky survey (Karachentsev et al.\cite{Karachentsev00) and 81 objects from a supplementary list ofcandidate dwarf galaxies (Karachentseva & Karachentsev\cite{Karachentseva00}). This yields a total of 165 (=17 + 67 + 81)galaxies. Overall we have a detection rate of 48%. The sample ofdetected galaxies has the following median parameters: radial velocityVLG= 1127 km s-1, HI line width W50 =59 km s-1, absolute blue magnitude MBT0= -14.4 mag, linear diameter A0 = 4.0 kpc, hydrogenmass-to-luminosity ratio 1.6 Msun/Lsun. The sampleof known galaxies within the Local Volume increased from 179 in 1979(Kraan-Korteweg & Tammann \cite{KraanKorteweg79}) to 387 now. Thiscorresponds to an increase in total luminosity of 22%. The known HI massin the LV increased by 25%; the relative HI contentMHI/LB increased from 0.21 to 0.26 for the wholevolume. However we still might have missed half of the dwarf galaxies inthe Local Volume. Table 1 is also, and Table 2 only, available inelectronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr(139.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/377/801
| A supplementary list of southern nearby dwarf galaxy candidates
To improve the census of the Local Volume galaxies, we carried out asystematic search for nearby dwarf galaxies in a declination range of D< -18degr based on the ESO/SERC film copies. As a result, we presenta list of 81 nearby dwarf galaxy candidates of low surface brightnesswhich have angular diameters >~ 0farcm5 . Half of the objects havebeen found for the first time. This sample may be considered assupplementary to our list of 95 southern nearby dwarf galaxy candidates(A&AS, 1998, 127, 409) which have been detected in the samedeclination range around the known Local Volume galaxies. Figure 1 isonly available in electronic form at http://www.edpsciences.org
| 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.
| 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.
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