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Appearance and disappearance signals at a beta-Beam and a Super-Beam facility

A. Donini·E. Fernandez-Martinez·S. Rigolin
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Abstract

In this letter we present the study of the eightfold degeneracy in the $(θ_{13},δ)$ measurement including both appearance and disappearance channels. We analyse, for definiteness, the case of a standard low-$γ$ $β$-Beam and a 4 MWatt SPL Super-Beam facility, both aiming at a UNO-like Mton water Cerenkov detector located at the Frejus laboratory, $L = 130$ km. In the $β$-Beam case, the \nue disappearance channel does not improve the $(θ_{13},δ)$ measurement when a realistic (i.e. $\ge$ 2%) systematic error is included. In the Super-Beam case, the \numu disappearance channel could, instead, be quite useful in reducing the impact of the eightfold degeneracy in the $(θ_{13},δ)$ measurement, especially once the error on the atmospheric mass difference is fully taken into account in the fit.

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A. Donini, E. Fernandez-Martinez, S. Rigolin. 2005-08-28. Appearance and disappearance signals at a beta-Beam and a Super-Beam facility. https://doi.org/10.1016/j.physletb.2005.06.072

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