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arXiv · 1203.6012

Neutrino mass hierarchy and octant determination with atmospheric neutrinos

Vernon Barger·Raj Gandhi·Pomita Ghoshal·Srubabati Goswami·Danny Marfatia·Suprabh Prakash·Sushant K. Raut·S. Uma Sankar
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Abstract

The recent discovery by the Daya-Bay and RENO experiments, that θ_{13} is nonzero and relatively large, significantly impacts existing experiments and the planning of future facilities. In many scenarios, the nonzero value of θ_{13} implies that θ_{23} is likely to be different from π/4. Additionally, large detectors will be sensitive to matter effects on the oscillations of atmospheric neutrinos, making it possible to determine the neutrino mass hierarchy and the octant of θ_{23}. We show that a 50 kT magnetized liquid argon neutrino detector can ascertain the mass hierarchy with a significance larger than 4 sigma with moderate exposure times, and the octant at the level of 2-3 sigma with greater exposure.

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Vernon Barger, Raj Gandhi, Pomita Ghoshal, Srubabati Goswami, Danny Marfatia, Suprabh Prakash, Sushant K. Raut, S. Uma Sankar. 2012-09-04. Neutrino mass hierarchy and octant determination with atmospheric neutrinos. https://doi.org/10.1103/physrevlett.109.091801

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