SISSA Open Science

# Resolving parameter degeneracies in long-baseline experiments by atmospheric neutrino data

 dc.contributor.author Huber, Patrick en_US dc.contributor.author Maltoni, Michele en_US dc.contributor.author Schwetz, Thomas en_US dc.date.accessioned 2005 en_US dc.date.accessioned 2011-09-07T20:27:46Z dc.date.available 2005 en_US dc.date.available 2011-09-07T20:27:46Z dc.date.issued 2005 en_US dc.identifier.citation Phys. Rev. D 71 (2005) 053006 en_US dc.identifier.uri http://preprints.sissa.it/xmlui/handle/1963/1714 en_US dc.description.abstract In this work we show that the physics reach of a long-baseline (LBL) neutrino oscillation experiment based on a superbeam and a megaton water Cherenkov detector can be significantly increased if the LBL data are combined with data from atmospheric neutrinos (ATM) provided by the same detector. ATM data are sensitive to the octant of $\theta_{23}$ and to the type of the neutrino mass hierarchy, mainly through three-flavor effects in e-like events. This allows to resolve the so-called $\theta_{23}$- and sign($\Delta m^2_{31}$)-parameter degeneracies in LBL data. As a consequence it becomes possible to distinguish the normal from the inverted neutrino mass ordering at $2\sigma$ CL from a combined LBL+ATM analysis if $\sin^2 2\theta_{13} \gtrsim 0.02$. The potential to identify the true values of $\sin^2 2\theta_{13}$ and the CP-phase $\delta_{cp}$ is significantly increased through the lifting of the degeneracies. These claims are supported by a detailed simulation of the T2K (phase II) LBL experiment combined with a full three-flavor analysis of ATM data in the HyperKamiokande detector. en_US dc.format.extent 363537 bytes en_US dc.format.mimetype application/pdf en_US dc.language.iso en_US en_US dc.relation.ispartofseries SISSA;03/2005/EP en_US dc.relation.ispartofseries arXiv.org;hep-ph/0501037 en_US dc.relation.uri 10.1103/PhysRevD.71.053006 en_US dc.title Resolving parameter degeneracies in long-baseline experiments by atmospheric neutrino data en_US dc.type Preprint en_US dc.contributor.department Elementary Particle Theory en_US dc.contributor.area Physics en_US
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