Limits on nu_e and anti-nu_e disappearance from Gallium and reactor experiments

TL;DR

This paper investigates potential electron neutrino disappearance signals from Gallium and reactor experiments, suggesting possible neutrino oscillations with specific mixing parameters, and finds compatible hints across multiple datasets.

Contribution

It provides a combined analysis of Gallium and reactor experiment data, indicating consistent hints of electron neutrino disappearance and oscillation parameters.

Findings

Gallium experiments suggest neutrino disappearance with specific mixing parameters.

Bugey reactor data show a hint of oscillations compatible with Gallium results.

Combined data analyses strengthen the evidence for neutrino oscillations in the studied parameter space.

Abstract

The deficit observed in the Gallium radioactive source experiments is interpreted as a possible indication of the disappearance of electron neutrinos. In the effective framework of two-neutrino mixing we obtain $\sin^{2}2\vartheta \gtrsim 0.03$ and $\Delta{m}^{2} \gtrsim 0.1 \text{eV}^{2}$. The compatibility of this result with the data of the Bugey and Chooz reactor short-baseline antineutrino disappearance experiments is studied. It is found that the Bugey data present a hint of neutrino oscillations with $0.02 \lesssim \sin^{2}2\vartheta \lesssim 0.08$ and $\Delta{m}^{2} \approx 1.8 \text{eV}^{2}$, which is compatible with the Gallium allowed region of the mixing parameters. This hint persists in the combined analyses of Bugey and Chooz data, of Gallium and Bugey data, and of Gallium, Bugey, and Chooz data.