A Monte Carlo Approach to Magnetar-powered Transients. I. Hydrogen-deficient Superluminous Supernovae

Abstract

In this paper we collect 19 hydrogen-deficient superluminous supernovae (SLSNe) and fit their light curves, temperature evolution, and velocity evolution based on the magnetar-powered model. To obtain the best-fitting parameters, we incorporate the Markov chain Monte Carlo approach. We get rather good fits for seven events ( χ 2 /dof = 0.24–0.96) and good fits for another seven events ( χ 2 /dof = 1.37–3.13). We find that the initial periods ( P 0 ) and magnetic strength ( B p ) of the magnetars that supposedly power these SLSNe are in the range of ∼1.2–8.3 ms and G, respectively; the inferred masses of the ejecta of these SLSNe are between 1 and , and the values of the gamma-ray opacity are between 0.01 and 0.82 cm 2 g −1 . We also calculate the fraction of the initial rotational energy of the magnetars harbored in the centers of the remnants of these SLSNe that is converted to the kinetic energy of the ejecta and find that the fraction is ∼19%–97% for different values of P 0 and B p , indicating that the acceleration effect cannot be neglected. Moreover, we find that the initial kinetic energies of most of these SLSNe are so small ( erg) that they can be easily explained by the neutrino-driven mechanism. These results can help clarify some important issues related to the energy-source mechanisms and explosion mechanisms and reveal the nature of SLSNe.