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arXiv · 2401.13120

On the source contribution to the Galactic diffuse gamma rays above 398 TeV detected by the Tibet AS{\gamma} 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 AS{\gamma} experiment is an important key to interpreting recent multi-messenger observations. This paper reveals a surprising fact: none of the 23 Tibet AS{\gamma} 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 AS{\gamma} diffuse gamma-ray events. No positional overlap between the Tibet AS{\gamma} diffuse gamma-ray events and the sub-PeV LHAASO sources currently supports the diffusive nature of the Tibet AS{\gamma} 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 AS{\gamma} experiment. https://arxiv.org/abs/2401.13120

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