SN 2020wnt: a slow-evolving carbon-rich superluminous supernova with no O ii lines and a bumpy light curve

• DOI: 10.1093/mnras/stac2747
• Publication Date: 2022-09-23T21:39:07Z
• Authors: C P Gutiérrez; A Pastorello; M Bersten; S Benetti; M Orellana; A Fiore; E Karamehmetoglu; T Kravtsov; A Reguitti; T M Reynolds; G Valerin; P Mazzali; M Sullivan; Y-Z Cai; N Elias-Rosa; M Fraser; E Y Hsiao; E Kankare; R Kotak; H Kuncarayakti; Z Li; S Mattila; J Mo; S Moran; P Ochner; M Shahbandeh; L Tomasella; X Wang; S Yan; J Zhang; T Zhang; M D Stritzinger
• Keywords: Absolute magnitude; Pair-instability supernova

ABSTRACT We present the analysis of SN 2020wnt, an unusual hydrogen-poor superluminous supernova (SLSN-I), at a redshift 0.032. The light curves 2020wnt are characterized by early bump lasting ∼5 d, followed bright main peak. reaches peak absolute magnitude M$_{r}^{\rm max}=-20.52\pm 0.03$ mag ∼77.5 d from explosion. This is lower end luminosity distribution SLSNe-I, but rise-time one longest reported to date. Unlike other spectra do not show O ii, strong lines C ii and Si detected. Spectroscopically, resembles Type Ic 2007gr, its evolution significantly slower. Comparing bolometric curve hydrodynamical models, we find that can be explained radioactive powering. progenitor likely massive extended star with pre-SN mass 80 M⊙ radius 15 R⊙ experiences very energetic explosion 45 × 1051 erg, producing 4 56Ni. In this framework, first results post-shock cooling phase for progenitor, luminous due large nickel production. These characteristics compatible pair-instability scenario. note, however, significant contribution interaction circumstellar material cannot ruled out.