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arXiv · 0806.2649

Hints of theta_13>0 from global neutrino data analysis

G. L. Fogli·E. Lisi·A. Marrone·A. Palazzo·A. M. Rotunno
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Abstract

Nailing down the unknown neutrino mixing angle theta_13 is one of the most important goals in current lepton physics. In this context, we perform a global analysis of neutrino oscillation data, focusing on theta_13, and including recent results [Neutrino 2008, Proceedings of the XXIII International Conference on Neutrino Physics and Astrophysics, Christchurch, New Zealand, 2008 (unpublished)]. We discuss two converging hints of theta_13>0, each at the level of ~1sigma: an older one coming from atmospheric neutrino data, and a newer one coming from the combination of solar and long-baseline reactor neutrino data. Their combination provides the global estimate sin^2(theta_13) = 0.016 +- 0.010 (1sigma), implying a preference for θ_13>0 with non-negligible statistical significance (~90% C.L.). We discuss possible refinements of the experimental data analyses, which might sharpen such intriguing indication.

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G. L. Fogli, E. Lisi, A. Marrone, A. Palazzo, A. M. Rotunno. 2008-10-03. Hints of theta_13>0 from global neutrino data analysis. https://doi.org/10.1103/physrevlett.101.141801

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