Bulk Neutrinos as an Alternative Cause of the Gallium and Reactor Anti-neutrino Anomalies

TL;DR

This paper proposes that neutrino oscillations into sterile Kaluza-Klein modes in extra dimensions could explain the observed deficits in Gallium and reactor anti-neutrino experiments, fitting existing data without conflicting with other neutrino results.

Contribution

It introduces a novel model where neutrinos oscillate into sterile Kaluza-Klein modes in extra dimensions to explain neutrino anomalies, supported by data analysis.

Findings

Data from Gallium and short-baseline reactor experiments fit the model.

Compatible neutrino mass and extra dimension size ranges are identified.

Model remains consistent with other neutrino oscillation constraints.

Abstract

We consider an alternative explanation for the deficit of nu_e in Ga solar neutrino calibration experiments and of the anti nu_e in short baseline reactor experiments by a model where neutrinos can oscillate into sterile Kaluza-Klein modes that can propagate in compactified sub-micrometer flat extra dimensions. We have analyzed the results of the Gallium radioactive source experiments and 19 reactor experiments with baseline shorter than 100 m, and showed that these data can be fitted into this scenario. The values of the lightest neutrino mass and of the size of the largest extra dimension that are compatible with these experiments are mostly not excluded by other neutrino oscillation experiments.