Tau contribution and precision measurement of theta23 at a neutrino factory

Abstract

We discuss precision measurements of the leading atmospheric parameters at a standard neutrino factory. The oscillation of the muon and electron neutrinos (anti-neutrinos) to tau neutrinos (anti-neutrinos) adds to the muon events sample (both right sign and wrong sign) via leptonic decays of the taus produced through charge-current interactions in the detector. We focus on how this contribution affects a precision measurement of the atmospheric mixing parameters and the deviation of muon neutrino -- tau neutrino mixing from maximality.Comment: 4 pages, 5 figures, presented by NS at the 11th International Workshop on Neutrino Factories, Superbeams and Beta Beams (Nufact09), July 20-25, 2009, Illinois Institute of Technology, Chicago, US