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arXiv · 2605.17636

Diffuse gamma-ray emission in the vicinity of open cluster Berkeley 87

Ziwei Ou·Xiaolong Yang
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Abstract

Young massive stellar clusters have been recognized as a significant population of cosmic ray accelerators and gamma-ray sources. We report the detection of extended gamma-ray emission toward the young massive star cluster Berkeley 87 using 18 years of Fermi-LAT data. The hadronic scenario is favored given the dense gas and the cluster's strong stellar winds. The cluster can supply sufficient energy to power the observed gamma-ray emission. A nearby pulsar, PSR J2021+3651, associated with the Dragonfly pulsar wind nebula and the 4HWC source 4HWC J2021+3650, lies in the same field of view. We also discuss the maximum accelerated proton energy and electron energy density of this pulsar.

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Ziwei Ou, Xiaolong Yang. 2026-09-22. Diffuse gamma-ray emission in the vicinity of open cluster Berkeley 87. https://doi.org/10.1093/mnras%2Fstag1680

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