Early versus late type galaxies in compact groups
  We find a strong correlation between the effective radius of the largest early-type galaxies in compact groups of galaxies and the velocity dispersion of the groups. The lack of a similar correlation for late type galaxies is supportive of the so called second generation merging scenario which predicts that ellipticals should dominate the internal dynamics of the groups, while late-type galaxies are mainly recent interlopers which are still in an early stage of interaction with the group potential. 
A.A.Shaker (NRIAG Egypt, Osservatorio Astronomico di Capodimonte),   G.Longo (Osservatorio Astronomico di Capodimonte) P.Mer...