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arXiv · 2212.01088

Upper limits on the isotropic diffuse flux of cosmic PeV photons from Carpet-2 observations

D. D. Dzhappuev·Yu. Z. Afashokov·I. M. Dzaparova·T. A. Dzhatdoev·E. A. Gorbacheva·I. S. Karpikov·M. M. Khadzhiev·N. F. Klimenko·A. U. Kudzhaev·A. N. Kurenya·A. S. Lidvansky·O. I. Mikhailova·V. B. Petkov·E. I. Podlesnyi·N. A. Pozdnukhov·V. S. Romanenko·G. I. Rubtsov·S. V. Troitsky·I. B. Unatlokov·I. A. Vaiman·A. F. Yanin·K. V. Zhuravleva
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Abstract

Isotropic diffuse gamma-ray flux in the PeV energy band is an important tool for multimessenger tests of models of the origin of high-energy astrophysical neutrinos and for new-physics searches. So far, this flux has not yet been observed. Carpet-2 is an air-shower experiment capable of detecting astrophysical gamma rays with energies above 0.1 PeV. Here we report the upper limits on the isotropic gamma-ray flux from Carpet-2 data obtained in 1999-2011 and 2018-2022. These results, obtained with the new statistical method based on the shape of the muon-number distribution, summarize Carpet-2 observations as the upgraded installation, Carpet-3, starts its operation.

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D. D. Dzhappuev, Yu. Z. Afashokov, I. M. Dzaparova, T. A. Dzhatdoev, E. A. Gorbacheva, I. S. Karpikov, M. M. Khadzhiev, N. F. Klimenko, A. U. Kudzhaev, A. N. Kurenya, A. S. Lidvansky, O. I. Mikhailova, V. B. Petkov, E. I. Podlesnyi, N. A. Pozdnukhov, V. S. Romanenko, G. I. Rubtsov, S. V. Troitsky, I. B. Unatlokov, I. A. Vaiman, A. F. Yanin, K. V. Zhuravleva. 2022-12-02. Upper limits on the isotropic diffuse flux of cosmic PeV photons from Carpet-2 observations. https://doi.org/10.1134/s0021364022603244

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