The Rate of Supernovae at Redshift 0.1-1.0 - the Stockholm VIMOS
  Supernova Survey IV
  We present supernova rate measurements at redshift 0.1-1.0 from the Stockholm
VIMOS Supernova Survey (SVISS). The sample contains 16 supernovae in total. The
discovered supernovae have been classified as core collapse or type Ia
supernovae (9 and 7, respectively) based on their light curves, colour
evolution and host galaxy photometric redshift. The rates we find for the core
collapse supernovae are 3.29 (-1.78,-1.45)(+3.08,+1.98) x 10^-4 yr^-1 Mpc^-3
h70^3 (with statistical and systematic errors respectively) at average redshift
0.39 and 6.40 (-3.12,-2.11)(+5.30,+3.65) x 10^-4 yr^-1 Mpc^-3 h70^3 at average
redshift 0.73. For the type Ia supernovae we find a rate of 1.29
(-0.57,-0.28)(+0.88,+0.27) x 10^-4 yr^-1 Mpc^-3 h70^3 at average redshift 0.62.
All of these rate estimates have been corrected for host galaxy extinction,
using a method that includes supernovae missed in infrared bright galaxies at
high redshift. We use Monte Carlo simulations to make a thorough study of the
systematic effects from assumptions made when calculating the rates and find
that the most important errors come from misclassification, the assumed mix of
faint and bright supernova types and uncertainties in the extinction
correction. We compare our rates to other observations and to the predicted
rates for core collapse and type Ia supernovae based on the star formation
history and different models of the delay time distribution. Overall, our
measurements, when taking the effects of extinction into account, agree quite
well with the predictions and earlier results. Our results highlight the
importance of understanding the role of systematic effects, and dust extinction
in particular, when trying to estimate the rates of supernovae at moderate to
high redshift.
