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arXiv · 0909.1535

Confusing non-zero theta_13 with non-standard interactions in the solar neutrino sector

A. Palazzo·J. W. F. Valle
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Abstract

Solar and KamLAND data are in slight tension when interpreted in the standard two-flavor oscillations framework and this may be alleviated allowing for a non-zero value of the mixing angle theta_13. Here we show that, likewise, non-standard flavor-changing interactions (FCI), possibly intervening in the propagation of solar neutrinos, are equally able to alleviate this tension and therefore constitute a potential source of confusion in the determination of theta_13. By performing a full three-flavor analysis of solar and KamLAND data in presence of FCI we provide a quantitative description of the degeneracy existing between theta_13 and the vectorial coupling eps_eτ^dV characterizing the non-standard transitions between nu_e and nu_tau in the forward scattering process with d-type quarks. We find that couplings with magnitude eps_eτ^dV ~ 10%, compatible with the existing bounds, can mimic the non-zero values of theta_13 indicated by the latest analyses.

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A. Palazzo, J. W. F. Valle. 2009-12-01. Confusing non-zero theta_13 with non-standard interactions in the solar neutrino sector. https://doi.org/10.1103/physrevd.80.091301

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