STAR-FORMATION IN SOUTHERN SEYFERT-GALAXIES

We have produced radio maps, using the Australia Telescope Compact Arr ay, of the central regions of six southern type 2 Seyfert galaxies (NG C 1365, 4945, 6221, 6810, 7582 and Circinus) with circumnuclear star f ormation, to estimate the relative contribution of star formation acti vity compared to activity from the active galactic nucleus (AGN). The radio morphologies range from extended diffuse structures to compact n uclear emission, with no evidence, even in the relatively compact sour ces, for synchrotron self-absorption. In each case the radio to far-in frared (FIR) ratio has a value consistent with star formation, and in all but one case the radio to [Fe rr] ratio is also consistent with st ar formation. We derive supernova rates and conclude that, despite the presence of a Seyfert nucleus in these galaxies, the radio, FIR and [ Fe II] line emissions are dominated by processes associated with the c ircumnuclear star formation (i.e. supernova remnants and H rr regions) rather than with the AGN.