VLA 20 cm survey of poor groups of galaxies

Journal Article · Tue Sep 01 04:00:00 EDT 1987 · Astron. J.; (United States)

DOI:https://doi.org/10.1086/114494· OSTI ID:5710953

Burns, J O; Nelson, E R; Morrisette, K A; Hanisch, R J; White, R A

The paper reports on VLA 20 cm observations of an extensive sample of galaxies in 139 poor groups. These groups, composed of galaxies down to the limit of the Zwicky et al. (CGCG) catalog, were chosen using a percolation algorithm set at a high surface-density threshold. Approximately 50 percent of the groups have measured redshifts. These groups were surveyed using a snapshot mode of the VLA with a resolution of about 13 arcsec. Analysis of the resulting radio and optical properties reveals that the presence of a nearby companion galaxy has an important role in generating radio emission in a galaxy. CCD observations of two radio-loud, disturbed galaxies with companions are presented and are used to discuss models of radio-source production. Nine tailed radio galaxies are found in the poor groups, which is much more than had been expected from previous work on rich clusters and from theoretical models. The paper discusses previous statistical biases and proposes a method for bending head-tail sources in poor groups. From the confinement of extended radio features associated with tailed sources, the presence of a substantial intracluster medium that should radiate significantly at soft-X-ray energies is predicted. 56 references.

• Research Organization: New Mexico Univ., Albuquerque; Space Telescope Science Institute, Baltimore, MD; Applied Research Corp., Landover, MD
• OSTI ID: 5710953
• Journal Information: Astron. J.; (United States), Journal Name: Astron. J.; (United States) Vol. 94; ISSN ANJOA
• Country of Publication: United States
• Language: English

Related Subjects

640105* -- Astrophysics & Cosmology-- Galaxies
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
COSMIC RADIO SOURCES
ELECTROMAGNETIC RADIATION
GALAXIES
GALAXY CLUSTERS
INTERGALACTIC SPACE
IONIZING RADIATIONS
RADIATIONS
RADIO GALAXIES
RADIOWAVE RADIATION
RED SHIFT
SOFT X RADIATION
SPACE
VISIBLE RADIATION
X RADIATION