Classification of colliding galaxies - II

Abstract

In our Paper I we had classified galaxies in increasing order of the intensity of tidal effects on the basis of transfer of energy from the motion of galaxies to the internal motions. This work has been refined by presenting the classification on the basis of the velocity of collision, which is an observable parameter. Analytic expressions are obtained for Vdis, the maximum velocity required for the disruption of one of the galaxies and Vcap, the maximum velocity required for mutual capture of the galaxies, in terms of collision parameters. Examples of some observed pairs of galaxies for the classification types are given.