Summary: Wolf­Rayet Phenomena in Massive Stars and Starburst Galaxies
Proceedings IAU Symposium No. 193, c
fl1999 IAU
K.A. van der Hucht, G. Koenigsberger & P.R.J. Eenens, eds.
When supernovae explode in a starburst: transitions
among AGN types
Itziar Aretxaga
Instituto Nacional de Astrof'isica, '
Optica y Electr'onica,
Aptdo. Postal 51 y 216, Puebla, Pue., Mexico
Abstract. Among the Active Galactic Nuclei that have suffered type muta­
tions, the classically classified Seyfert 2 NGC 7582 recently found at a Seyfert 1
stage, is perhaps one of the most puzzling cases, since it defies a well supported
case for unification. We investigate the possibility that this type transition,
common to another twelve AGN, is driven by supernovae exploding in a nu­
clear/circumnuclear starburst.
1. Introduction
Variability is a common characteristic of AGN. Most variability studies concen­
trate their attention on luminous Seyfert 1 nuclei and QSOs, which are known
to develop prominent variations. But even among brands which classically have

Source: Aretxaga, Itziar - Instituto Nacional de Astrofísica Óptica y Electrónica

Collections: Physics