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تسجيل مستخدم جديدSearches for Sterile Neutrinos with the IceCube Detector
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The IceCube neutrino telescope at the South Pole has measured the atmospheric muon neutrino spectrum as a function of zenith angle and energy in the approximate 320 GeV to 20 TeV range, to search for the oscillation signatures of light sterile neutrinos. No evidence for anomalous $ u_mu$ or $bar{ u}_mu$ disappearance is observed in either of two independently developed analyses, each using one year of atmospheric neutrino data. New exclusion limits are placed on the parameter space of the 3+1 model, in which muon antineutrinos would experience a strong MSW-resonant oscillation. The exclusion limits extend to $mathrm{sin}^2 2theta_{24} leq$ 0.02 at $Delta m^2 sim$ 0.3 $mathrm{eV}^2$ at the 90% confidence level. The allowed region from global analysis of appearance experiments, including LSND and MiniBooNE, is excluded at approximately the 99% confidence level for the global best fit value of $|$U$_{e4}|^2$.
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