Are Kronberger 80 and/or Kronberger 82 regions PeVatron candidates for LHAASO J2108+5157?
Artikel i vetenskaplig tidskrift, 2025

High-energy gamma-rays have been detected in the region of LHAASO J2108+5157 by the Fermi-LAT, HAWC and LHAASO-KM2A observatories. Cygnus OB2 in Cygnus-X has been confirmed as the first strong stellar cluster PeVatron in our Galaxy. Thus, the star-forming regions Kronberger 80 and Kronberger 82, located in the field of LHAASO J2108+5157, are analyzed to evaluate their stellar population and potential as associated PeVatron candidates. A distance of 10 kpc is adopted for Kronberger 80, while $\sim$1.6 kpc is estimated for Kronberger 82. Based on stellar densities, we report that their cluster radii are ${2{<^>{\prime }_{.}}5}$ and ${2{<^>{\prime }_{.}}0}$, while infrared photometry reveals poor stellar content in massive O-type stars in both cases. From optical data, the estimations of cluster ages are 5-12.6 and $\lesssim$5 Myr, respectively. We conclude that, in contrast to the stellar content of Cygnus OB2, it is unlikely that Kronberger 80 and Kronberger 82 are PeVatrons associated with LHAASO J2108+5157. The presence of a PeVatron in this region remains a mystery, but we confirm that the two Kronberger regions are star-forming regions undergoing formation rather than evolution.

ISM: individual objects (LHAASO J2108+5157, Kronberger 80, Kronberger 82)

gamma rays: ISM

ISM: clouds

ISM: molecules

Författare

Akash Gupta

Universität zu Köln

Eduardo de la Fuente

Universidad de Guadalajara

University of Tokyo

Ram K. Yadav

Natl Astron Res Inst Thailand Publ Org

Alicia Porras

Instituto Nacional de Astrofísica, Óptica y Electrońica

Saurabh Sharma

Aryabhatta Research Institute of Observational Sciences

Sei Kato

University of Tokyo

Sorbonne Université

Daniel Tafoya

Chalmers, Rymd-, geo- och miljövetenskap, Onsala rymdobservatorium

Miguel A. Trinidad

Universidad de Guanajuato

Universidad de Guadalajara

Harold E. Viveros

Universidad de Guanajuato

Kazumasa Kawata

Sorbonne Université

Hiromasa Suzuki

Japan Aerospace Exploration Agency (JAXA)

Munehiro Ohnishi

Sorbonne Université

Ivan Toledano-Juarez

Universidad de Guadalajara

Takashi Sako

Sorbonne Université

Masato Takita

Sorbonne Université

Publication of the Astronomical Society of Japan

0004-6264 (ISSN) 2053051x (eISSN)

Vol. In Press

Ämneskategorier (SSIF 2025)

Astronomi, astrofysik och kosmologi

DOI

10.1093/pasj/psaf046

Mer information

Senast uppdaterat

2025-06-16