COMPACT-GROUPS OF GALAXIES, MERGING AND NUCLEAR ACTIVITY

Correlations of multiwavelenght standard parameters, such as radio power, optical and infrared luminosity, were attempted for Hickson Compact Group and Markarian galaxies. Galaxies were then divided into classes according to their nuclear activity properties and interacting status, to achieve clear understanding bf the activity-interaction relation. Data indicate that Seyferts in compact groups are mostly of type 2, but not that galaxies in compact groups undergo a general enhancement in their activity level. Globally there is no significant difference between interacting and non interacting Markarian Seyferts, although strong evidence is found that infrared luminosity is a good tracer of interaction for the reddest (U-B > -0.3) Seyfert 1 systems. It is also found that interacting Starburst galaxies in the Markarian sample do not look like pre-Seyferts. Thus, if indeed nuclear emission is a consequence of interaction, as claimed by many authors, the observational parameters which can provide statistically convincing evidence have not yet been identified.