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تسجيل مستخدم جديدSearch for Very High Energy Gamma Rays from the Northern $textit{Fermi}$ Bubble Region with HAWC
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We present a search of very high energy gamma-ray emission from the Northern $textit{Fermi}$ Bubble region using data collected with the High Altitude Water Cherenkov (HAWC) gamma-ray observatory. The size of the data set is 290 days. No significant excess is observed in the Northern $textit{Fermi}$ Bubble region, hence upper limits above $1,text{TeV}$ are calculated. The upper limits are between $3times 10^{-7},text{GeV}, text{cm}^{-2}, text{s}^{-1},text{sr}^{-1}$ and $4times 10^{-8},text{GeV},text{cm}^{-2},text{s}^{-1},text{sr}^{-1}$. The upper limits disfavor a proton injection spectrum that extends beyond $100,text{TeV}$ without being suppressed. They also disfavor a hadronic injection spectrum derived from neutrino measurements.
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