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تسجيل مستخدم جديدThe Core-collapse rate from the Supernova Legacy Survey
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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 $i^primesim24$. 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 $4.5pm0.8(stat.) pm0.6 (sys.)$. This corresponds to a core-collapse rate at $z=0.3$ of $[1.42pm 0.3(stat.) pm0.3(sys.)]times10^{-4}yr^{-1}(h_{70}^{-1}Mpc)^{-3}$.
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