Monte Carlo simulations of supernova light curves and the hypernova SN 1998bw

We propose a method for computing the bolometric light curves of type Ia and Ib/c supernovae based on Monte Carlo simulations of unsteady-state radiative transfer The method is used to analyze the bolometric light curve of the unusual type Ib/c supernova SN 1998bw associated with GRB 980 425. We show that the previously noted inconsistency in the behavior of simulated light curves at early and late stages, which is attributable to asymmetry effects, can be overcome in a spherically symmetric model. Agreement with observations requires complete Ni-56 mixing and a higher matter density in the central part of the envelope in the velocity range v < 5000 km s(-1) compared to standard models. (C) 2000 MAIK Nauka/Interperiodica.