Constraining the TeV gamma-ray emission of SN 2024bch, a possible type IIn-L from a red supergiant progenitor Multiwavelength observations and analysis of the progenitor

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61989592%3A15310%2F25%3A73632894" target="_blank" >RIV/61989592:15310/25:73632894 - isvavai.cz</a>

Result on the web

<a href="https://www.aanda.org/articles/aa/pdf/2025/10/aa54721-25.pdf" target="_blank" >https://www.aanda.org/articles/aa/pdf/2025/10/aa54721-25.pdf</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1051/0004-6361/202554721" target="_blank" >10.1051/0004-6361/202554721</a>

Result language

angličtina

Original language name

Constraining the TeV gamma-ray emission of SN 2024bch, a possible type IIn-L from a red supergiant progenitor Multiwavelength observations and analysis of the progenitor

Original language description

We present very high-energy optical photometry and spectroscopic observations of SN 2024bch in the nearby galaxy NGC 3206 (∼20 Mpc). We used gamma-ray observations performed with the first Large-Sized Telescope (LST-1) of the Cherenkov Telescope Array Observatory (CTAO) and optical observations with the Liverpool Telescope (LT) combined with data from public repositories to evaluate the general properties of the event and the progenitor star. No significant emission above the LST-1 energy threshold for this observation (∼100 GeV) was detected in the direction of SN 2024bch, and we computed an integral upper limit on the photon flux of Fγ(&gt;100 GeV) ≤ 3.61 × 10−12 cm−2 s−1 based on six nonconsecutive nights of observations with the LST-1, between 16 and 38 days after the explosion. Employing a general model for the gamma-ray flux emission, we found an upper limit on the mass-loss-rate to wind-velocity ratio of M· /uw ≤ 10−4 Myr kms , although gamma-gamma absorption could potentially have skewed this estimation, effectively weakening our constraint. From spectro-photometric observations we found progenitor parameters of Mpr = 11 – 20 M and Rpr = 531 ± 125 R . Finally, using archival images from the Hubble Space Telescope, we constrained the luminosity of the progenitor star to log (Lpr/L ) ≤ 4.82 and its effective temperature to Tpr ≤ 4000 K. Our results suggest that SN 2024bch is a type IIn-L supernova that originated from a progenitor star consistent with a red supergiant. We show how the correct estimation of the mass-loss history of a supernova will play a major role in future multiwavelength observations.

Czech name

—

Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

10303 - Particles and field physics

Project

Result was created during the realization of more than one project. More information in the Projects tab.

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Publication year

2025

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Astronomy and Astrophysics

ISSN

0004-6361

e-ISSN

1432-0746

Volume of the periodical

702

Issue of the periodical within the volume

OCT

Country of publishing house

FR - FRANCE

Number of pages

12

Pages from-to

"A125-1"-"A125-12"

UT code for WoS article

001638041700001

EID of the result in the Scopus database

2-s2.0-105021474070