SN 2018hti was a very nearby (z=0.0614) superluminous supernova with an exceedingly bright absolute magnitude of -21.7 mag in r-band at maximum. The densely sampled pre-maximum light curves of SN 2018hti show a slow luminosity evolution and constrain the rise time to ~50 rest-frame days. We fitted synthetic light curves to the photometry to infer the physical parameters of the explosion of SN 2018hti for both the magnetar and the CSM-interaction scenarios. We conclude that one of two mechanisms could be powering the luminosity of SN 2018hti; interaction with ~10 Msun of circumstellar material or a magnetar with a magnetic field of B_p~1.3e13 G and initial period of P_spin~1.8 ms. From the nebular spectrum modelling we infer that SN 2018hti likely results from the explosion of a ~40 Msun progenitor star.
@article{arxiv.2111.07142,
title = {Close, bright and boxy: the superluminous SN 2018hti},
author = {A. Fiore and S. Benetti and M. Nicholl and A. Reguitti and E. Cappellaro and S. Campana and S. Bose and E. Paraskeva and E. Berger and T. M. Bravo and J. Burke and Y. -Z. Cai and T. -W. Chen and P. Chen and R. Ciolfi and S. Dong and S. Gomez and M. Gromadzki and C. P. Gutiérrez and D. Hiramatsu and G. Hosseinzadeh and D. A. Howell and A. Jerkstrand and E. Kankare and A. Kozyreva and K. Maguire and C. McCully and P. Ochner and C. Pellegrino and G. Pignata and R. S. Post and N. Elias-Rosa and M. Shahbandeh and S. Schuldt and B. P. Thomas and L. Tomasella and J. Vinkó and C. Vogl and J. C. Wheeler and D. R. Young},
journal= {arXiv preprint arXiv:2111.07142},
year = {2022}
}
Comments
31 pages, 19 figures, replaced after acceptance by MNRAS (minor revisions compared to the previous version)