| Abstract | H I and radio continuum observations of the close group of galaxies NGC 2805, NGC 2814, NGC 2820 and IC 2458 are presented. H I is detected in all except NGC 2814, and there is good evidence for a H I bridge linking NGC 2820 and IC 2458. The radio continuum emission is not significantly different from that of 'normal' galaxies, being consistent with nuclear sources in NGC 2820, NGC 2814 and possibly IC 2458. It is postulated that the H I bridge and disturbed nature of this group are the results of a tidal interaction, in which either NGC 2814 or NGC 2805 passed within one galactic radii of a proto-NGC 2820 about 0.3 Gyr ago, in an approximately co-planar orbit. As a result the H I (originally surrounding NGC 2820) was drawn out to form a large tidal arm, in which IC 2458 is now embedded. The integrated properties for the galaxies are discussed, and those of IC 2458 are consistent with an Ir type. |
