An H  I survey of highly flattened, edge-on, pure disk galaxies

¹ National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903, U.S.A.
² Unité Scientifique Nançay, CNRS B704, Observatoire de Paris, 5 place Jules Janssen, 92195 Meudon, France

Send offprint request to: L.D. Matthews, e-mail: lmatthew@nrao.edu

Received: 30 November 1999
Accepted: 2 February 2000

Abstract

We have undertaken an 21-cm line survey of 472 late-type, edge-on spiral galaxies using the NançayRadio Telescope and the Green Bank 140-Foot Telescope. Our targets consisted of highly inclined spirals with large disk axial ratios and little or no bulge component–i.e., highly flattened, pure disk galaxies. These objects were primarily selected from the Flat Galaxy Catalogue (FGC) of Karachentsev et al. (1993). Most were classified as Hubble types Scd or later, with an emphasis on the largest angular size and lowest optical surface brightness objects in the FGC. Our detection rate was %, underscoring that relatively small, gas-rich, moderate-to-low surface brightness pure disk spirals are an extremely common constituent of the nearby universe. Our data also suggest that the most highly flattened spirals are primarily isolated systems. The majority of our detected galaxies had no previously published redshifts or data. Here we present parameters for the 239 detected sources and 45 marginal detections, together with search limits for the undetected galaxies.