Hidden Interactions of Sterile Neutrinos As a Probe For New Physics

TL;DR

This paper investigates hidden interactions of sterile neutrinos mediated by a MeV-scale gauge boson, using MINOS data to constrain new physics scenarios and exclude certain parameter regions, including solutions to the muon g-2 anomaly and cosmological conflicts.

Contribution

The study introduces constraints on sterile neutrino hidden interactions with a MeV-scale gauge boson using MINOS data, providing new limits on model parameters and ruling out some proposed solutions to existing anomalies.

Findings

Excluded interaction strength G_X/G_F > 92.4 at 2σ confidence level.

Ruled out the parameter space for the (g-2)_μ discrepancy for M_X < 100 MeV.

Excluded sterile neutrino secret interactions with g'_s > 1.6×10^{-2} for certain couplings.

Abstract

Recent results from neutrino experiments show evidence for light sterile neutrinos which do not have any Standard Model interactions. In this work we study the hidden interaction of sterile neutrinos with an "MeV scale" gauge boson (the $\nu_s$HI model) with mass $M_X$ and leptonic coupling $g^\prime_l$. By performing an analysis on the $\nu_s$HI model using the data of the MINOS neutrino experiment we find that the values above $G_X/G_F=92.4$ are excluded by more than $2\sigma$ C.L., where $G_F$ is the Fermi constant and $G_X$ is the field strength of the $\nu_s$HI model. Using this model we can also probe other new physics scenarios. We find that the region allowed by the $(g-2)_\mu$ discrepancy is entirely ruled out for $M_X\lesssim 100$ MeV. Finally, the secret interaction of sterile neutrinos has been to solve a conflict between the sterile neutrinos and cosmology. It is shown here that such an interaction is excluded by MINOS for $g^\prime_s> 1.6\times10^{-2}$. This exclusion, however, does depend on the value of $g_l^{\prime}$.