The environments of type Ibn supernovae: evidence for a strong Wolf-Rayet star component
Abstract
Characterisation of progenitor stars of supernovae (SNe) poses several challenges. Direct observations of progenitors are based on serendipitious archival observations and are only possible for nearby events. Indirect methods include inferring nickel mass from the light curves or oxygen masses from the SN's nebular phase, both of which are tools to constrain the progenitor's initial mass. Alternatively, environments of SNe have been used as a proxy for the progenitor's age and metallicity. The progenitor channel of type Ibn SNe is a hotly debated topic. The mass-loss and the formation of He-rich circumstellar medium requires strong envelope stripping of the progenitor star. For core-collapse supernovae (CCSNe), this requires strong stellar wind mass losses, i.e. a Wolf-Rayet (WR) star, or binary interaction with a companion star. Here, we analyse a sample of host galaxies of type Ibn SNe that have been observed with MUSE. We use Hα emission to infer the transient's association to star formation and derive the local metallicity with commonly used strong line diagnostic. We find that the sample of SNe are highly associated with star formation in the host galaxy, typically situated within one of the brightest HII regions in the host galaxy. The NCR distribution of Hα pixels in SN Ibn environments strongly resembles that of WR stars, and shows a stronger preference to SF compared to other core-collapse SN types. Metallicity measurements show typically sub-solar metallicity in the SN environments.
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BibTeX
@misc{kravtsov2026environments,
title = {{The environments of type Ibn supernovae: evidence for a strong Wolf-Rayet star component}},
author = {Timo Kravtsov and Hanindyo Kuncarayakti and Joseph P. Anderson},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.27931},
eprint = {2610.27931},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.27931},
note = {CC BY-SA 4.0},
}
RIS
TY - UNPB
TI - The environments of type Ibn supernovae: evidence for a strong Wolf-Rayet star component
AU - Timo Kravtsov
AU - Hanindyo Kuncarayakti
AU - Joseph P. Anderson
PY - 2026
DA - 2026/10/20
PB - arXiv
DO - 10.48550/arxiv.2610.27931
UR - https://arxiv.org/abs/2610.27931
AB - Characterisation of progenitor stars of supernovae (SNe) poses several challenges. Direct observations of progenitors are based on serendipitious archival observations and are only possible for nearby events. Indirect methods include inferring nickel mass from the light curves or oxygen masses from the SN's nebular phase, both of which are tools to constrain the progenitor's initial mass. Alternatively, environments of SNe have been used as a proxy for the progenitor's age and metallicity. The progenitor channel of type Ibn SNe is a hotly debated topic. The mass-loss and the formation of He-rich circumstellar medium requires strong envelope stripping of the progenitor star. For core-collapse supernovae (CCSNe), this requires strong stellar wind mass losses, i.e. a Wolf-Rayet (WR) star, or binary interaction with a companion star. Here, we analyse a sample of host galaxies of type Ibn SNe that have been observed with MUSE. We use Hα emission to infer the transient's association to star formation and derive the local metallicity with commonly used strong line diagnostic. We find that the sample of SNe are highly associated with star formation in the host galaxy, typically situated within one of the brightest HII regions in the host galaxy. The NCR distribution of Hα pixels in SN Ibn environments strongly resembles that of WR stars, and shows a stronger preference to SF compared to other core-collapse SN types. Metallicity measurements show typically sub-solar metallicity in the SN environments.
ER -