Type Ib Supernovae are bluer than Type Ic Supernovae
Abstract
Type Ib and Ic supernovae (SNe Ib/Ic) are the bright finale of massive stars that have lost their hydrogen envelopes, making them powerful probes of mass stripping in massive star evolution. The advent of modern large photometric and spectroscopic surveys presents the unique opportunity to investigate systematic differences between these two kinds of SNe. In this study, we analyze a large, homogeneous sample of SNe Ib/Ic light curves from the Zwicky Transient Facility. We find a systematic difference in their optical colors: SNe Ib are, on average, bluer than SNe Ic at a statistically significant level. This difference appears intrinsic, likely reflecting progenitors with different degrees of stripping -- helium-rich for SNe Ib and helium-poor for SNe Ic. In addition, we find that SNe Ib/Ic with narrow lines (SNe Ibn/Icn) are bluer than those without, which might originate from circumstellar matter interaction, with potential connection to fast blue optical transients. We demonstrate that SN colors offer a promising probe of mass stripping in massive stars, potentially providing a useful tool for analyzing large photometric data and improving predictions for the final outcomes of stripped massive stars.
Cite
@article{arxiv.2605.01200,
title = {Type Ib Supernovae are bluer than Type Ic Supernovae},
author = {Harim Jin and Selma E. de Mink and Sebastian Holzner and Jakub Klencki and Géza Csörnyei and Sung-Chul Yoon and Iair Arcavi and Wolfgang E. Kerzendorf},
journal= {arXiv preprint arXiv:2605.01200},
year = {2026}
}
Comments
Submitted to A&A