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تسجيل مستخدم جديدEvidence of theta(13)>0 from global neutrino data analysis
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The neutrino mixing angle theta(13) is at the focus of current neutrino research. From a global analysis of the available oscillation data in a 3-neutrino framework, we previously reported [Phys. Rev. Lett. 101, 141801 (2008)] hints in favor of theta(13)>0 at the 90 % C.L. Such hints are consistent with the recent indications of nu(mu)-->nu(e) appearance in the T2K and MINOS long-baseline accelerator experiments. Our global analysis of all the available data currently provides >3 sigma evidence for nonzero theta(13), with 1-sigma ranges sin^2 theta(13) = 0.021+-0.007 or 0.025+-0.007, depending on reactor neutrino flux systematics. Updated ranges are also reported for the other 3-neutrino oscillation parameters (delta m^2, sin^2 theta(12)) and (Delta m^2, sin^2 theta(23)).
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At the previous Venice meeting NO-VE 2008, we discussed possible hints in favor of a nonzero value for the unknown neutrino mixing angle theta(13), emerging from the combination of solar and long-baseline reactor data, as well as from the combination
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