Results of a systematic search for outburst events in 1.4 million
  galaxies
  We present an analysis of nine years of Catalina Surveys optical photometry
for 1.4 million spectroscopically confirmed SDSS galaxies. We find 717 outburst
events that were not reported by ongoing transient surveys. These events have
timescales ranging from weeks to years. More than two thirds of these new
events are found in starforming galaxies, while such galaxies only constitute
~20% of our sample. Based on the properties of the hosts and events, we find
that almost all of the new events are likely to be associated with regular
supernovae. However, a small number of long-timescale events are found among
the galaxies containing AGN. These events have similar properties to those
recently found in the analyses of light curves of large samples of AGN. Given
the lack of such events among the more than a million passive galaxies in the
sample, we suggest that the long outbursts are associated with super-massive
black holes or their environments.
