SN 2020jfo: A Short-plateau Type II Supernova from a Low-mass Progenitor

Abstract

We present spectroscopic and photometric observations of the Type IIP supernova, SN 2020jfo, in ultraviolet and optical wavelengths. SN 2020jfo occurred in the spiral galaxy M61 (NGC 4303), with eight observed supernovae in the past 100 yr. SN 2020jfo exhibited a short plateau lasting < 65 days, and achieved a maximum brightness in Vband of MV = −17.4 ± 0.4 mag at about 8.0 ± 0.5 days since explosion. From the bolometric light curve, we have estimated the mass of 56Ni synthesized in the explosion to be 0.033 ± 0.006 Me. The observed spectral features are typical for a Type IIP supernova except for shallow Hα absorption throughout the evolution and the presence of stable 58Ni feature at 7378 Å, in the nebular phase. Using hydrodynamical modeling in the MESA + STELLA framework, an ejecta mass of ∼5 Me is estimated. Models also indicate SN 2020jfo could be the result of a red supergiant progenitor with MZAMS ∼ 12 Me. Bolometric light-curve modeling revealed the presence of a secondary radiation source for initial ∼20 days, which has been attributed to interaction with a circumstellar material of mass ∼ 0.2 Me, which most likely was ejected due to enhanced mass loss about 20 yr prior to the supernova explosion.