Supernova 2020wnt: An Atypical Superluminous Supernova with a Hidden Central Engine

Samaporn Tinyanont, Stan E. Woosley, Kirsty Taggart, Ryan J. Foley, Lin Yan, Ragnhild Lunnan, Kyle W. Davis, Charles D. Kilpatrick, Matthew R. Siebert, Steve Schulze, Chris Ashall, Ting Wan Chen, Kishalay De, Georgios Dimitriadis, Dillon Z. Dong, Christoffer Fremling, Alexander Gagliano, Saurabh W. Jha, David O. Jones, Mansi M. KasliwalHao Yu Miao, Yen Chen Pan, Daniel A. Perley, Vikram Ravi, César Rojas-Bravo, Itai Sfaradi, Jesper Sollerman, Vanessa Alarcon, Rodrigo Angulo, Karoli E. Clever, Payton Crawford, Cirilla Couch, Srujan Dandu, Atirath Dhara, Jessica Johnson, Zhisen Lai, Carli Smith

研究成果: 雜誌貢獻期刊論文同行評審

5 引文 斯高帕斯(Scopus)

摘要

We present observations of a peculiar hydrogen- and helium-poor stripped-envelope (SE) supernova (SN) 2020wnt, primarily in the optical and near-infrared (near-IR). Its peak absolute bolometric magnitude of −20.9 mag (L bol, peak = (6.8 ± 0.3) × 1043 erg s−1) and a rise time of 69 days are reminiscent of hydrogen-poor superluminous SNe (SLSNe I), luminous transients potentially powered by spinning-down magnetars. Before the main peak, there is a brief peak lasting <10 days post explosion, likely caused by interaction with circumstellar medium (CSM) ejected ∼years before the SN explosion. The optical spectra near peak lack a hot continuum and O ii absorptions, which are signs of heating from a central engine; they quantitatively resemble those of radioactivity-powered hydrogen/helium-poor Type Ic SESNe. At ∼1 yr after peak, nebular spectra reveal a blue pseudo-continuum and narrow O i recombination lines associated with magnetar heating. Radio observations rule out strong CSM interactions as the dominant energy source at +266 days post peak. Near-IR observations at +200-300 days reveal carbon monoxide and dust formation, which causes a dramatic optical light-curve dip. Pair-instability explosion models predict slow light curve and spectral features incompatible with observations. SN 2020wnt is best explained as a magnetar-powered core-collapse explosion of a 28 M pre-SN star. The explosion kinetic energy is significantly larger than the magnetar energy at peak, effectively concealing the magnetar-heated inner ejecta until well after peak. SN 2020wnt falls into a continuum between normal SNe Ic and SLSNe I, and demonstrates that optical spectra at peak alone cannot rule out the presence of a central engine.

原文???core.languages.en_GB???
文章編號34
期刊Astrophysical Journal
951
發行號1
DOIs
出版狀態已出版 - 1 7月 2023

指紋

深入研究「Supernova 2020wnt: An Atypical Superluminous Supernova with a Hidden Central Engine」主題。共同形成了獨特的指紋。

引用此