Supernova Discoveries 2010-2011: Statistics and Trends
  We have inspected all supernova discoveries reported during 2010 and 2011
(538 and 926 events, respectively). We examine the statistics of all discovered
objects, as well as those of the subset of spectroscopically-confirmed events.
In these two years we see the rise of wide-field non-targeted supernova surveys
to prominence, with the largest numbers of events reported by the CRTS and PTF
surveys (572 and 393 events in total respectively, contributing together 74% of
all reported discoveries in 2011), followed by the integrated contribution of
numerous amateurs (184 events). Among spectroscopically-confirmed events the
PTF (393 events) leads, followed by CRTS (170 events), and amateur discoveries
(144 events). Traditional galaxy-targeted surveys, such as LOSS and CHASE,
maintain a strong contribution (86 and 61 events, respectively) with high
spectroscopic completeness (~90% per cent). It is interesting to note that the
community managed to provide substantial spectroscopic follow-up for relatively
brighter amateur discoveries (<m>=16.5 mag), but significant less help for
fainter (and much more numerous) events promptly released by the CRTS (<m>=18.6
mag). Inspecting discovery magnitude and redshift distributions we find that
PS1 discoveries have similar properties (<m>=21.6 mag, <z>=0.23) to events
found in previous seasons by cosmology-oriented projects (e.g., SDSS-II), while
PTF (<m>=19.2 mag, <z>=0.095) and CRTS (<m>=18.6 mag, <z>=0.049) populate the
relatively unexplored phase space of faint SNe (>19 mag) in nearby galaxies
(mainly PTF), and events at 0.05<z<0.2 (CRTS and PTF). Examining the specific
question of reporting channels over the previous dozen years, we find that
traditional reports via CBET telegrams now account only for a minority of SN
discoveries.
