In this study we present the results of a five-year follow-up campaign of the long-lived type IIn supernova SN 2017hcc, found in a spiral dwarf host of near-solar metallicity. The long rise time (57 ± 2 days, ATLAS o band) and high luminosity (peaking at −20.78 ± 0.01 mag in the ATLAS o band) point towards an interaction of massive ejecta with massive and dense circumstellar material (CSM). The evolution of SN 2017hcc is slow, both spectroscopically and photometrically, reminiscent of the long-lived type IIn, SN 2010jl. An infrared (IR) excess was apparent soon after the peak, and blueshifts were noticeable in the Balmer lines starting from a few hundred days, but appeared to be fading by around +1200 days. We posit that an IR light echo from pre-existing dust dominates at early times, with some possible condensation of new dust grains occurring at epochs >∼+800 days.
@article{arxiv.2210.14076,
title = {A long life of excess: The interacting transient SN 2017hcc},
author = {S. Moran and M. Fraser and R. Kotak and A. Pastorello and S. Benetti and S. J. Brennan and C. P. Gutiérrez and E. Kankare and H. Kuncarayakti and S. Mattila and T. M. Reynolds and J. P. Anderson and P. J. Brown and S. Campana and K. C. Chambers and T. -W. Chen and M. Della Valle and M. Dennefeld and N. Elias-Rosa and L. Galbany and F. J. Galindo-Guil and M. Gromadzki and D. Hiramatsu and C. Inserra and G. Leloudas and T. E. Müller-Bravo and M. Nicholl and A. Reguitti and M. Shahbandeh and S. J. Smartt and L. Tartaglia and D. R. Young},
journal= {arXiv preprint arXiv:2210.14076},
year = {2023}
}