| Title: |
SN 2016dsg: A Thermonuclear Explosion Involving a Thick Helium Shell |
| Authors: |
Dong, Y; Valenti, S; Polin, A; Boyle, A; Flörs, A; Vogl, C; Kerzendorf, WE; Sand, DJ; Jha, SW; Wyrzykowski, Ł; Bostroem, KA; Pearson, J; McCully, C; Andrews, JE; Benetti, S; Blondin, S; Galbany, L; Gromadzki, M; Hosseinzadeh, G; Howell, DA; Inserra, C; Jencson, JE; Lundquist, M; Lyman, JD; Magee, M; Maguire, K; Meza, N; Srivastav, S; Taubenberger, S; Terwel, JH; Wyatt, S; Young, DR |
| Publisher Information: |
American Astronomical Society |
| Publication Year: |
2026 |
| Collection: |
Oxford University Research Archive (ORA) |
| Description: |
A thermonuclear explosion triggered by a He-shell detonation on a carbon–oxygen white-dwarf core has been predicted to have strong UV line blanketing at early times due to the iron-group elements produced during He-shell burning. We present the photometric and spectroscopic observations of SN 2016dsg, a subluminous peculiar Type I supernova consistent with a thermonuclear explosion involving a thick He shell. With a redshift of 0.04, the i -band peak absolute magnitude is derived to be around −17.5. The object is located far away from its host, an early-type galaxy, suggesting it originated from an old stellar population. The spectra collected after the peak are unusually red, show strong UV line blanketing and weak O i λ 7773 absorption lines, and do not evolve significantly over 30 days. An absorption line around 9700–10500 Å is detected in the near-infrared spectrum and is likely from the unburnt He in the ejecta. The spectroscopic evolution is consistent with the thermonuclear explosion models for a sub-Chandrasekhar-mass white dwarf with a thick He shell, while the photometric evolution is not well described by existing models. |
| Document Type: |
article in journal/newspaper |
| Language: |
English |
| DOI: |
10.3847/1538-4357/ac75eb |
| Availability: |
https://doi.org/10.3847/1538-4357/ac75eb; https://ora.ox.ac.uk/objects/uuid:53a76ab5-76f4-407a-885d-6732766a5ec2 |
| Rights: |
info:eu-repo/semantics/openAccess ; CC Attribution (CC BY) |
| Accession Number: |
edsbas.88CA914F |
| Database: |
BASE |