Zusammenfassung
We study the incidence of nuclear activity in a large sample of massive
post-starburst galaxies at z~0.7 selected from the Sloan Digital Sky Survey,
and identify active galactic nuclei based on radio continuum and optical
emission lines. Over our mass range of 10^10.6-10^11.5 Msun, the incidence of
radio activity is weakly dependent on stellar mass and independent of stellar
age, while radio luminosity depends strongly on stellar mass. Optical nuclear
activity incidence depends most strongly on the Dn4000 line index, a proxy for
stellar age, with an active fraction that is ~ten times higher in the youngest
versus oldest post-starburst galaxies. Since a similar trend is seen between
age and molecular gas fractions, we argue that, like in local galaxies, the age
trend reflects a peak in available fueling rather than feedback from the
central black hole on the surrounding galaxy.
Nutzer