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تسجيل مستخدم جديدNew limit on high Galactic latitude PeV gamma-ray flux from Tibet AS-gamma data
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Tibet AS-gamma collaboration has recently reported detection of gamma-rays with energies up to Peta-electronvolt from parts of the Galactic plane. We notice that the analysis of gamma-ray flux by the Tibet AS-gamma experiment also implies an upper bound on the diffuse gamma-ray flux from high Galactic latitudes(|b|>20 degrees) in the energy range between 100 TeV and 1 PeV. This bound is up to an order-of-magnitude stronger than previously derived bounds from GRAPES3, KASCADE and CASA-MIA experiments. We discuss the new TibetAS-gamma limit on high Galactic latitude gamma-ray flux in the context of possible mechanisms of multi-messenger (gamma-ray and neutrino) emission from nearby cosmic ray sources, dark matter decays and large scale cosmic ray halo of the Milky Way.
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Tibet-AS$gamma$ collaboration has recently reported a measurement of diffuse $gamma$-ray flux from the outer Galactic disk in the energy range reaching PeV. We complement this measurement with the Fermi/LAT measurement of the diffuse flux from the sa
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