In this paper we study nonstandard neutrino interactions as an example of physics beyond the standard model using atmospheric neutrino data collected during the Super-Kamiokande I (1996-2001) and II (2003-2005) periods. We focus on flavor-changing-neutral-currents (FCNC), which allow neutrino flavor transitions via neutral current interactions, and effects which violate lepton nonuniversality and give rise to different neutral-current interaction- amplitudes for different neutrino flavors. We obtain a limit on the FCNC coupling parameter, ε μτ, |ε μτ|< 1.1×10 -2 at 90% C.L. and various constraints on other FCNC parameters as a function of the nonuniversality coupling, ε ee. We find no evidence of nonstandard neutrino interactions in the Super-Kamiokande atmospheric data.
|Journal||Physical Review D - Particles, Fields, Gravitation and Cosmology|
|Publication status||Published - 2011 Dec 14|