Can the hint of $\delta_{CP}$ from T2K also indicate the hierarchy and octant ?

Monojit Ghosh; Srubabati Goswami; Sushant K. Raut

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arXiv · 1507.01794

Can the hint of $\delta_{CP}$ from T2K also indicate the hierarchy and octant ?

Monojit Ghosh·Srubabati Goswami·Sushant K. Raut

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Abstract

The T2K neutrino data has already given a hint for the best-fit value of the leptonic CP phase $\delta_{CP}$ as $-90^\circ$. In this paper we ask the question that if this hint is confirmed by the subsequent neutrino and anti-neutrino runs of T2K, then can it also give any information about the other two remaining unknown oscillation parameters - the neutrino mass hierarchy and octant of $\theta_{23}$. We find that if T2K runs in only neutrino mode with its full targeted exposure, then $\delta_{CP} = -90^\circ$ would indicate the true hierarchy as normal and the true octant as higher. On the other hand if T2K runs in equal neutrino and anti-neutrino mode then the true hierarchy can be confirmed as normal but the octant will remain undetermined. We have also studied the effect of anti-neutrino runs on CP sensitivity of T2K.

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Monojit Ghosh, Srubabati Goswami, Sushant K. Raut. 2015-07-07. Can the hint of $\delta_{CP}$ from T2K also indicate the hierarchy and octant ?. https://arxiv.org/abs/1507.01794

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