Global Analysis of the Source and Detector Nonstandard Interactions Using the Short Baseline Neutrino- and Antineutrino-Electron Scattering Data

TL;DR

This paper conducts a comprehensive analysis of nonstandard neutrino interactions at sources and detectors using short-baseline electron scattering data, improving bounds and refining the weak mixing angle measurement.

Contribution

It provides the first combined analysis of source and detector nonstandard interactions in short-baseline experiments, yielding new bounds and a more precise measurement of the weak mixing angle.

Findings

Stronger bounds on certain nonstandard parameters from combined analysis.

New limits on source and detector nonstandard interactions.

A 2% improved measurement of the weak mixing angle.

Abstract

We present a global analysis of the semileptonic and purely Leptonic nonuniversal and flavor-changing nonstandard neutrino interactions in all the known short-baseline neutrino- and antineutrino-electron scattering experiments. The nonstandard effects at the source and at the detector can be more transparent in these experiments because of the negligibly small ratio between the baselines and the neutrino energies, which is not enough for the neutrinos to oscillate, and thus can be sensitive to the new physics at the both ends. We use data from two electron-neutrino electron scattering experiments and six electron-antineutrino electron scattering experiments and combine them to find the best fits on the nonstandard parameters using the source-only, detector-only analyses, and then find the interplay between the two cases. The bounds obtained in some cases are stronger and new, in some cases comparable to the current ones, and in the other cases weaker. For instance, the bound obtained from the interplay between the source and detector nonstandard physics on the nonstandard parameter {\epsilon}_{ee}^{udL} at the source is much stronger and is comparable with the indirect bound, but the bounds on the parameters {\epsilon}_{{\mu}e}^{udL} and {\epsilon}_{{\tau}e}^{udL} are weaker in this study in comparison with the indirect bounds. We also find a global fit on the standard weak mixing angle sin{\theta}_{W}=0.249+-0.020 with 2% improvement in its precision in comparison with the previous studies.