Multi-Wavelength Identification of a Luminous Mid-Infrared Supernova Powered by Circumstellar Interaction with Binary-Driven Pre-supernova Mass Loss

@misc{uno2026multiwavelength,
  title = {{Multi-Wavelength Identification of a Luminous Mid-Infrared Supernova Powered by Circumstellar Interaction with Binary-Driven Pre-supernova Mass Loss}},
  author = {Kohki Uno and Kishalay De and Geoffrey Mo and Viraj Karambelkar and Kaitlyn Shin and Christoffer Fremling and Jesper Sollerman and Daichi Hiramatsu and Jacob E. Jencson},
  howpublished = {arXiv},
  year = {2026},
  month = sep,
  doi = {10.48550/arxiv.2609.09520},
  eprint = {2609.09520},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2609.09520},
  note = {CC0},
}

TY  - UNPB
TI  - Multi-Wavelength Identification of a Luminous Mid-Infrared Supernova Powered by Circumstellar Interaction with Binary-Driven Pre-supernova Mass Loss
AU  - Kohki Uno
AU  - Kishalay De
AU  - Geoffrey Mo
AU  - Viraj Karambelkar
AU  - Kaitlyn Shin
AU  - Christoffer Fremling
AU  - Jesper Sollerman
AU  - Daichi Hiramatsu
AU  - Jacob E. Jencson
PY  - 2026
DA  - 2026/09/08
PB  - arXiv
DO  - 10.48550/arxiv.2609.09520
UR  - https://arxiv.org/abs/2609.09520
AB  - Terminal mass-loss in massive stars is commonly reconstructed from observations of circumstellar interaction in core-collapse supernovae (CCSNe); however, such signatures can be easily missed depending on the phase when they appear. In this paper, we present a multi-wavelength study of SN\,2022yyz, a nearby CCSN selected by its luminous late-time mid-infrared (MIR) excess in NEOWISE at > 500 days after the discovery. Classified as a Type II SN at discovery, it reached a peak bolometric luminosity of 1.3^+0.7_−0.4×10^43 erg s^−1 before fading away with a light-curve drop at ∼ 300 days. We present late-time HST/WFC3 ultraviolet (UV) imaging and Keck/LRIS spectroscopy at ∼ 1200 days, which reveal clear signs of circumstellar-medium (CSM) interaction via a UV excess consistent with a strong MgII contribution and a flat-topped Hα profile. We show that the bolometric light curve and the late-time UV luminosity can be explained using a semi-analytic CSM interaction model involving a broken power-law density profile: with ∼ 2.7 M_⊙ of nearby, dense CSM within a radius of ∼ 10^16 cm surrounded by wind-like outer CSM with a mass-loss rate of ∼ 10^−4 ~M_⊙ yr^−1. The broken density profile indicates ≳ 100× mass-loss rate enhancement starting a few hundred years before explosion, pointing to a possible common-envelope ejection in a binary system. Despite being overlooked for follow-up at such proximity, our results demonstrate that IR photometric selection methods provide a powerful way of mapping terminal mass-loss in massive stars - laying the groundwork for the Roman Space Telescope surveys.
ER  -