  Ever since the co-existence of an active galactic nucleus (AGN) and a
starburst was observationally discovered, there has been a significant
controversy over whether there is a physical connection between starbursts and
AGNs. If yes, it is a subject of interest to reveal which one triggers another.
Here we bring a unique insight onto the subject by identifying 840 galaxies
with both a post-starburst signature (strong Balmer absorption lines) and an
AGN (based on the emission line ratio). These poststarburst-AGNs account for
the 4.2% of all the galaxies in a volume-limited sample. The presence of a
post-starburst phase with an active AGN itself is of importance, suggesting
that AGNs may outlive starbursts in the starburst-AGN connection. In addition,
we have performed spatially resolved spectroscopy of three of our
poststarbusrst-AGN galaxies, obtaining some evidence that the post-starburst
region is more extended, but sharply centred around the central AGN, confirming
a spatial connection between the post-starburst and the AGN.

Astrophysics