The Radio Luminosity-risetime Function of Core-collapse Supernovae

Abstract

Abstract We assemble a large set of 2–10 GHz radio flux density measurements and upper limits of 294 different supernovae (SNe), from the literature and our own and archival data. Only 31% of SNe were detected. We characterize the SN radio lightcurves near the peak using a two-parameter model, with t pk being the time to rise to a peak and L pk the spectral luminosity at that peak. Over all SNe in our sample at D < 100 Mpc, we find that t pk = 101.7±0.9 days and that L pk = 1025.5±1.6 erg s−1 Hz−1, and therefore that generally 50% of SNe will have L pk < 1025.5 erg s−1 Hz−1. These L pk values are ∼30 times lower than those for only detected SNe. Types Ib/c and II (excluding IIn’s) have similar mean values of L pk but the former have a wider range, whereas Type IIn SNe have ∼10 times higher values with L pk = 1026.5±1.1 erg s−1 Hz−1. As for t pk, Type Ib/c have t pk of only 101.1±0.5 days while Type II have t pk = 101.6±1.0 and Type IIn the longest timescales with t pk = 103.1±0.7 days. We also estimate the distribution of progenitor mass-loss rates, , and find that the mean and standard deviation of are −5.4 ± 1.2 (assuming v wind = 1000 km s−1) for Type Ib/c SNe, and −6.9 ± 1.4 (assuming v wind = 10 km s−1) for Type II SNe excluding Type IIn.