| Abstract : | We present the optical photometry and spectroscopy of SN 2013he, a Type II Plateau supernova (SN II-P) in NGC 4774. SN 2013he is a luminous (MV ≲ -18 mag) event with a relatively short recombination phase, of ∼80 days. The distance to the supernova is estimated to be 126.02 ± 0.30 Mpc using the expanding photosphere method. The spectra display typical features of expanding supernova ejecta including the P-Cygni profiles observed for the H Balmer and He-I components. The evolution of the H-α line profile, shows signatures of ejecta-CSM interaction after the early plateau phases, pointing towards the possibility of significant mass loss prior to the explosion, effectively stripping the progenitor’s H-rich envelope. The bolometric light curve and its semi-analytical modeling are used to estimate the explosion parameters of SN 2013he such as Mej (ejecta mass), progenitor radius R0. Our estimates support the idea of a massive red supergiant progenitor, with an initial mass of roughly 18-20 M⊙. The obtained characteristics of SN 2013he, suggest that it falls in a transitional class of Type II supernovae, the short plateau supernovae (SPSNe), a fairly luminous class of SNe, which also exhibit signatures of early ejecta-CSM interactions.
|
