Galaxy Interactions in the Local Volume

Abstract

Imaging of a large number of faint galaxies with the Hubble Space Telescope reveals a significant excess of interacting and peculiar objects among them (Griffiths et al.,1994, Burkey et al., 1994). Being expected in general, this result needs, however, to be expressed quantitatively. To estimate evolutionary changing of the relative number of interacting galaxies, δ_int(z), from their redshift z, one must determine reliably the local value, δ_int(0). But due to a subjective manner of definition of interacting galaxy system, the published values of δ_int(0) differ from one author to another several times. The most appropriate sample to estimate δ_int(0) would be quite a representative sample of very nearby galaxies, which is restricted by their distance or radial velocity. Below we consider data on such a fair sample, named the Local Volume (=LV), which is the most complete one at the present moment.