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arXiv · 0711.2018

Sterile neutrinos after the first MiniBooNE results

Abstract

In view of the recent results from the MiniBooNE experiment we revisit the global neutrino oscillation fit to short-baseline neutrino data by adding one, two or three sterile neutrinos with eV-scale masses to the three Standard Model neutrinos. We find that four-neutrino oscillations of the (3+1) type, which have been only marginally allowed before the recent MiniBooNE results, become even more disfavored with the new data. In the framework of so-called (3+2) five-neutrino mass schemes the MiniBooNE results can be nicely reconciled with the LSND appearance evidence thanks to the possibility of CP violation available in such oscillation schemes; however, the tension between appearance and disappearance experiments represents a serious problem in (3+2) schemes, so that these models are ultimately not viable. This tension remains also when a third sterile neutrino is added, and we do not find a significant improvement of the global fit in a (3+3) scheme.

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Michele Maltoni. 2007-12-04. Sterile neutrinos after the first MiniBooNE results. https://doi.org/10.1088/1742-6596/110/8/082011

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