A radio-detected Type Ia supernova with helium-rich circumstellar material
Abstract
Type Ia supernovae (SNe Ia) are thermonuclear explosions of degenerate white dwarf (WD) stars destabilized by mass accretion from a companion star, but the nature of their progenitors remains poorly understood. A way to discriminate between progenitor systems is through radio observations; a non-degenerate companion star is expected to lose material through winds or binary interaction prior to explosion, and the SN ejecta crashing into this nearby circumstellar material (CSM) should result in radio synchrotron emission. However, despite extensive efforts, no SN Ia has ever been detected at radio wavelengths, which suggests a clean environment and a companion star that is itself a degenerate WD star. Here we report on the study of SN 2020eyj, a SN Ia showing helium-rich CSM, as revealed by its spectral features, infrared emission and, for the first time in a SN Ia, a radio counterpart. Based on our modeling, we conclude the CSM likely originates from a single-degenerate (SD) binary system where a WD accretes material from a helium donor star, an often hypothesized formation channel for SNe Ia. We describe how comprehensive radio follow-up of SN 2020eyj-like SNe Ia can improve the constraints on their progenitor systems.
Keywords
Cite
@article{arxiv.2210.07725,
title = {A radio-detected Type Ia supernova with helium-rich circumstellar material},
author = {Erik C. Kool and Joel Johansson and Jesper Sollerman and Javier Moldón and Takashi J. Moriya and Steve Schulze and Laura Chomiuk and Chelsea Harris and Miguel Pérez-Torres and Seppo Mattila and Peter Lundqvist and Matthew Graham and Sheng Yang and Daniel A. Perley and Nora Linn Strotjohann and Christoffer Fremling and Avishay Gal-Yam and Jeremy Lezmy and Kate Maguire and Conor Omand and Mathew Smith and Igor Andreoni and Eric C. Bellm and Kishalay De and Joshua S. Bloom and Steven L. Groom and Mansi M. Kasliwal and Frank Masci and Michael Medford and Sungmin Park and Josiah Purdum and Tom M. Reynolds and Reed Riddle and Estelle Robert and Stuart D. Ryder and Yashvi Sharma and Daniel Stern},
journal= {arXiv preprint arXiv:2210.07725},
year = {2023}
}
Comments
62 pages, 10 figures, 4 tables