Detailed spectrophotometric analysis of the superluminous and fast evolving SN 2019neq

Achille Fiore; Stefano Benetti; Leonardo Tartaglia; Anders Jerkstrand; Irene Salmaso; Lina Tomasella; Antonia Morales-Garoffolo; Stefan Geier; Nancy Elias-Rosa; Enrico Cappellaro; Xiaofeng Wang; Jun Mo; Zhihao Chen; Shengyu Yan; Andrea Pastorello; Paolo A. Mazzali; Riccardo Ciolfi; Yongzhi Cai; Morgan Fraser; Claudia P. Gutiérrez; Emir Karamehmetoglu; Hanindyo Kuncarayakti; Shane Moran; Paolo Ochner; Andrea Reguitti; Thomas M. Reynolds; Giorgio Valerin

arXiv · 2311.13940

Detailed spectrophotometric analysis of the superluminous and fast evolving SN 2019neq

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Abstract

SN 2019neq was a very fast evolving superluminous supernova. At a redshift z=0.1059, its peak absolute magnitude was -21.5+/-0.2 mag in g band. In this work, we present data and analysis from an extensive spectrophotometric follow-up campaign using multiple observational facilities. Thanks to a nebular spectrum of SN 2019neq, we investigated some of the properties of the host galaxy at the location of SN 2019neq and found that its metallicity and specific star formation rate are in a good agreement with those usually measured for SLSNe-I hosts. We then discuss the plausibility of the magnetar and the circumstellar interaction scenarios to explain the observed light curves, and interpret a nebular spectrum of SN 2019neq using published SUMO radiative-transfer models. The results of our analysis suggest that the spindown radiation of a millisecond magnetar with a magnetic field B~6e14 G could boost the luminosity of SN 2019neq.

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Achille Fiore, Stefano Benetti, Leonardo Tartaglia, Anders Jerkstrand, Irene Salmaso, Lina Tomasella, Antonia Morales-Garoffolo, Stefan Geier, Nancy Elias-Rosa, Enrico Cappellaro, Xiaofeng Wang, Jun Mo, Zhihao Chen, Shengyu Yan, Andrea Pastorello, Paolo A. Mazzali, Riccardo Ciolfi, Yongzhi Cai, Morgan Fraser, Claudia P. Gutiérrez, Emir Karamehmetoglu, Hanindyo Kuncarayakti, Shane Moran, Paolo Ochner, Andrea Reguitti, Thomas M. Reynolds, Giorgio Valerin. 2023-11-23. Detailed spectrophotometric analysis of the superluminous and fast evolving SN 2019neq. https://arxiv.org/abs/2311.13940

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