A search for flavor-changing non-standard neutrino interactions using $\hat{I}{½}_e$ appearance in MINOS

Abstract

We report new constraints on flavor-changing non-standard neutrino interactions from the MINOS long-baseline experiment using $\hat{I}{½}_e$ and $\bar{\hat{I}}{½}_e$ appearance candidate events from predominantly $\hat{I}{½}_{\hat{I}}¼$ and $\bar{\hat{I}}{½}_{\hat{I}}¼$ beams. We used a statistical selection algorithm to separate $\hat{I}{½}_e$ candidates from background events, enabling an analysis of the combined MINOS neutrino and antineutrino data. We observe no deviations from standard neutrino mixing, and thus place constraints on the non-standard interaction matter effect, $|{\epsilon }_{e\ddot{I}„}|$, and phase, $(\hat{I}{´}_{CP}+\hat{I}{´}_{e\ddot{I}„})$, using a thirty-bin likelihood fit.

5 pages, 3 figures v2: References added, caption and probability calculation clarified. Result unchanged