Résumé du preprint Irfu-09-34

Irfu-09-34
The Core-collapse rate from the Supernova Legacy Survey
G. Bazin, N. Palanque-Delabrouille,J. Rich, V. Ruhlmann-Kleider, E. Aubourg, L. Le Guillou,P. Astier, C. Balland, S. Basa, R. G. Carlberg, A. Conley, D. Fouchez, J. Guy, D. Hardin, I. M. Hook, D. A. Howell, R. Pain, K. Perrett,C. J. Pritchet, N. Regnault, M. Sullivan, P. Antilogus,V. Arsenijevic, S. Baumont, S. Fabbro,J. Le Du, C. Lidman, M. Mouchet, A. Mour~ao, E. S. Walker
We use three years of data from the Supernova Legacy Survey (SNLS) to study the general properties of core-collapse and type Ia supernovae. This is the first such study using the ``rolling search\'\' technique which guarantees well-sampled SNLS light curves and good efficiency for supernovae brighter than $i^\\prime\\sim24$. Using host photometric redshifts, we measure the supernova absolute magnitude distribution down to luminosities $4.5\\,{\\rm mag}$ fainter than normal SNIa. Using spectroscopy and light-curve fitting to discriminate against SNIa, we find a sample of 117 core-collapse supernova candidates with redshifts $z<0.4$ (median redshift of 0.29) and measure their rate to be larger than the type Ia supernova rate by a factor $4.5\\pm0.8(stat.)\\, \\pm0.6 (sys.)$. This corresponds to a core-collapse rate at $z=0.3$ of $[1.42\\pm 0.3(stat.)\\,\\pm0.3(sys.)]\\times10^{-4}\\yr^{-1}(h_{70}^{-1}\\Mpc)^{-3}$.