The 1000 Brightest HIPASS Galaxies: Newly Cataloged Galaxies

Abstract

The HI Parkes All-Sky Survey (HIPASS) is a blind 21-cm survey for extragalactic neutral hydrogen, covering the whole southern sky. The HIPASS Bright Galaxy Catalog (BGC; Koribalski et al. 2002) is a subset of HIPASS and contains the 1000 HI-brightest (peak flux density) galaxies. Here we present the 138 HIPASS BGC galaxies, which had no redshift measured prior to the Parkes multibeam HI surveys. Of the 138 galaxies, 87 are newly cataloged. Newly cataloged is defined as no optical (or infrared) counterpart in the NASA/IPAC Extragalactic Database. Using the Digitized Sky Survey we identify optical counterparts for almost half of the newly cataloged galaxies, which are typically of irregular or magellanic morphological type. Several HI sources appear to be associated with compact groups or pairs of galaxies rather than an individual galaxy. The majority (57) of the newly cataloged galaxies lie within ten degrees of the Galactic Plane and are missing from optical surveys due to confusion with stars or dust extinction. This sample also includes newly cataloged galaxies first discovered in the HI shallow survey of the Zone-of-Avoidance (Henning et al. 2000). The other 30 newly cataloged galaxies escaped detection due to their low surface brightness or optical compactness. Only one of these, HIPASS J0546-68, has no obvious optical counterpart as it is obscured by the Large Magellanic Cloud. We find that the newly cataloged galaxies with |b| > 10 are generally lower in HI mass and narrower in velocity width compared with the total HIPASS BGC. In contrast, newly cataloged galaxies behind the Milky Way are found to be statistically similar to the entire HIPASS BGC. In addition to these galaxies, the HIPASS BGC contains four previously unknown HI clouds.Comment: 39 pages including 14 figures, to appear in the Oct 2002 issue of A

Neutral hydrogen surveys for high-redshift galaxy clusters and protoclusters

“…Emission and absorption of electromagnetic radiation due to transitions between the hyperfine states of neutral hydrogen (H I) (Field 1958) has had a significant impact on our understanding of our Galaxy and our immediate cosmic neighbourhood. At present, however, the highest redshift detection of 21-cm emission is at z ≈ 0.18 (Zwaan et al 2001) and only very shallow surveys (z < 0.04) of the whole sky have been performed (Zwaan et al 1997;Kilborn et al 1999;Ryan-Weber et al 2002;Lang et al 2003). In this article we would like to point out that it will soon be possible to perform blind unbiased searches for large objects, both virialized and collapsing, using 21-cm emission as their tracer.…”

Infrared signature of active massive black holes in nearby dwarf galaxies

“…Our method detected AGN in five galaxies that are closer than NGC 4395: HIPASS J1247-77 (3.2 Mpc), UGC 04459 (3.2 Mpc), NGC 5253 (3.6 Mpc), IC 2574 (3.8 Mpc) and CIRCINUS (4.2 Mpc). Of these, four can be classified as dwarf galaxies based on their stellar mass and/or absolute magnitude: HIPASS J1247-77 (Ryan-Weber et al 2002) has a magnitude M B = -12.91 (Karachentsev et al 2004), UGC 04459 has a stellar mass of ∼ 9.7 × 10 6 M and a magnitude M B = -13.43 ( Zhang et al 2012), NGC 5253 (Turner et al 2015) has a stellar mass of ∼ 1.5 × 10 8 M (Martin 1998) and IC 2574 has stellar mass of ∼ 6.3 × 10 7 M (Lee et al 2011) and a magnitude M B = -16.8 (Walter & Brinks 1999). The fifth galaxy, CIRCI-NUS, has a stellar mass of ∼ 9.5 × 10 10 M and is therefore not considered a dwarf galaxy ).…”

The HIPASS catalogue — III. Optical counterparts and isolated dark galaxies

“…Newly catalogued galaxies in the HIPASS Bright Galaxy Catalogue (BGC, Koribalski et al 2004), are described in Ryan-Weber et al (2002). Of the 1000 galaxies, 939 have optical counterparts, four are high-velocity clouds and 57 were deemed to be obscured by dust or confused with stars having galactic latitudes |b| < 10.…”