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arXiv · 2401.13120

On the source contribution to the Galactic diffuse gamma rays above 398 TeV detected by the Tibet ASγ experiment

S. Kato·D. Chen·J. Huang·T. Kawashima·K. Kawata·A. Mizuno·M. Ohnishi·T. Sako·T. K. Sako·M. Takita·Y. Yokoe
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Abstract

Potential contribution from gamma-ray sources to the Galactic diffuse gamma rays observed above 100 TeV (sub-PeV energy range) by the Tibet ASγ experiment is an important key to interpreting recent multi-messenger observations. This paper reveals a surprising fact: none of the 23 Tibet ASγ diffuse gamma-ray events above 398TeV within the Galactic latitudinal range of |b| < 10 deg. come from the 43 sub-PeV gamma-ray sources reported in the 1LHAASO catalog, which proves that these sources are not the origins of the Tibet ASγ diffuse gamma-ray events. No positional overlap between the Tibet ASγ diffuse gamma-ray events and the sub-PeV LHAASO sources currently supports the diffusive nature of the Tibet ASγ diffuse gamma-ray events, although their potential origin in the gamma-ray sources yet unresolved in the sub-PeV energy range cannot be ruled out.

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S. Kato, D. Chen, J. Huang, T. Kawashima, K. Kawata, A. Mizuno, M. Ohnishi, T. Sako, T. K. Sako, M. Takita, Y. Yokoe. 2024-01-23. On the source contribution to the Galactic diffuse gamma rays above 398 TeV detected by the Tibet ASγ experiment. https://arxiv.org/abs/2401.13120

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