Astron. Astrophys. Suppl. Ser. 139, 1-24

HI observations of blue compact galaxies from the first and second Byurakan surveys

Trinh X. Thuan¹³ - V.A. Lipovetsky$^{ \dag }$² - J.-M. Martin⁴ - S.A. Pustilnik²

Send offprint request: Trinh X. Thuan
$^{ \dag }\;$ Deceased 1996 September 22.

1 - Astronomy Department, University of Virginia, Charlottesville, VA 22903, U.S.A.
e-mail: txt@virginia.edu
2 - Special Astrophysical Observatory, Russian Academy of Sciences, Nizhnij Arkhyz, Karachai-Circessia 357147, Russia
e-mail: sap@sao.ru
3 - Département d'Astronomie Extragalactique et de Cosmologie, Observatoire de Paris, F-92195 Meudon Cedex, France
4 - Département de Radioastronomie ARPEGES, Observatoire de Paris, F-92195 Meudon Cedex, France
e-mail: jmmartin@obspm.fr

Received August 11; accepted November 24, 1998

Abstract:

We present the results of a neutral hydrogen survey of 79 galaxies from a statistical sample of 88 Blue Compact Galaxies (BCGs) selected from the First and Second Byurakan objective prism surveys to have a HII region-like spectrum, an equivalent width of the [O III] $\lambda 5007$ line larger than $\sim 50~{\mbox \AA}$, and a velocity $\leq 6000$ km s^-1. The detection rate for the statistical sample is 74%. HI masses range between $4\, 10^{7}M_{\hbox{$\odot$}}$ and $5~10^9 M_\odot$ with the HI mass distribution peaking at $3~10^8 M_{\hbox{$\odot$}}$. The full width at half-maximum of the HI profile varies between $\sim 30$ km s^-1 and 160 km s^-1, with a mean of $\sim$ 92 km s^-1. These small widths are characteristic of dwarf galaxies. For comparison, we have also observed an additional 92 BCGs with weaker star formation and/or larger distances, and/or interesting astrophysical properties. These in general have larger widths and HI masses.

Key words: galaxies: compact -- galaxies: ism -- galaxies: startburst -- radio lines: galaxies -- radio lines: ISM