Constraints on general neutrino interactions with exotic fermion from neutrino-electron scattering experiments

TL;DR

This paper analyzes constraints on general neutrino interactions with exotic fermions using neutrino-electron scattering data, providing bounds on various interaction types and discussing implications for dark matter detection.

Contribution

It offers a comprehensive analysis of neutrino-exotic fermion interactions across multiple experiments, including flavor dependence and implications for dark matter detection.

Findings

Borexino sets strongest bounds for electromagnetic dipole interactions at low mass.

CHARM-II dominates bounds for scalar, pseudoscalar, vector, axialvector, tensor interactions.

Vector interaction coefficients compatible with XENON1T data are allowed by neutrino experiments.

Abstract

The couplings between the neutrinos and exotic fermion can be probed in both neutrino scattering experiments and dark matter direct detection experiments. We present a detailed analysis of the general neutrino interactions with an exotic fermion and electrons at neutrino-electron scattering experiments. We obtain the constraints on the coupling coefficients of the scalar, pseudoscalar, vector, axialvector, tensor and electromagnetic dipole interactions from the CHARM-II, TEXONO and Borexino experiments. For the flavor-universal interactions, we find that the Borexino experiment sets the strongest bounds in the low mass region for the electromagnetic dipole interactions, and the CHARM-II experiment dominates the bounds for other scenarios. If the interactions are flavor dependent, the bounds from the CHARM-II or TEXONO experiment can be avoided, and there are correlations between the flavored coupling coefficients for the Borexino experiment. We also discuss the detection of sub-MeV DM absorbed by bound electron targets and illustrate that the vector coefficients preferred by XENON1T data is allowed by the neutrino experiments.