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تسجيل مستخدم جديدUpper limits for neutrino oscillations muon-antineutrino to electron-antineutrino from muon decay at rest
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The KARMEN experiment at the spallation neutron source ISIS used umub from mup--decay at rest in the search for neutrino oscillations umubnueb in the appearance mode, with p( ueb,e+)n as detection reaction of ueb. In total, 15 candidates fulfill all conditions for the ueb signature, in agreement with the background expectation of 15.8+-0.5 events, yielding no indication for oscillations. A single event based likelihood analysis leads to upper limits on the oscillation parameters: sin^2(2theta)<1.7x10e-3 for Dm^2>100 eV^2 and Dm^2<0.055 eV^2 for sin^2(2theta)=1 at 90% confidence. Thus, KARMEN does not confirm the LSND experiment and restricts significantly its favored parameter region for umubnueb.
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