ACTIVE GALACTIC NUCLEI AND NUCLEAR STARBURSTS

The Starburst model for radio-quiet Active Galactic Nuclei (AGN) postu lates that the activity seen in most AGN is powered solely by young st ars and compact supernova remnants (cSNR) in a burst of star formation at the time when the metal rich core of the spheroid of a normal earl y type galaxy was formed. In this model, the broad permitted lines cha racteristic of the Broad Line Region (BLR) and their variability origi nate in these cSNR. Detailed calculations of strong radiative cooling behind supernova shock waves evolving in a high density medium, combin ed with static photoionization computations, have shown that cSNR can reproduce most of the basic properties of the BLR in low luminosity AG N. We make definite, predictions about the lag, the observed delay bet ween sudden changes in the continuum ionizing radiation followed, afte r some time, by changes in the intensity of the emission lines from th e broad line region of AGNs. We have proposed that QSOs are the young metal rich cores of massive elliptical galaxies forming at z > 2.0. On ly a small fraction (approximately 5%) of the total mass of a normal e lliptical, the core mass, is needed to participate in a burst to expla in the observed luminosities and luminosity function of QSOs at z appr oximately 2.0. We predict that the progenitors of QSOs should look lik e dusty starbursts and be bout 4 times more luminous (in bolometric un its) and 10 times less frequent than QSOs themselves.