MicroBooNE and the $\nu_e$ Interpretation of the MiniBooNE Low-Energy Excess

TL;DR

This paper evaluates MicroBooNE's recent results in the context of the MiniBooNE low-energy excess, highlighting that current data do not fully exclude sterile neutrino explanations or a $ u_e$ interpretation, emphasizing the need for further analysis.

Contribution

The paper provides a quantitative assessment showing MicroBooNE results do not comprehensively test the MiniBooNE anomaly parameter space or the $ u_e$ interpretation in a model-independent manner.

Findings

MicroBooNE results do not fully exclude sterile neutrino models.

Current data do not comprehensively test the MiniBooNE anomaly.

Analysis code is publicly available for further research.

Abstract

A new generation of neutrino experiments is testing the $4.8\sigma$ anomalous excess of electron-like events observed in MiniBooNE. This is of huge importance for particle physics, astrophysics, and cosmology, not only because of the potential discovery of physics beyond the Standard Model, but also because the lessons we will learn about neutrino-nucleus interactions will be crucial for the worldwide neutrino program. MicroBooNE has recently released results that appear to disfavor several explanations of the MiniBooNE anomaly. Here, we show quantitatively that MicroBooNE results, while a promising start, unquestionably do not probe the full parameter space of sterile neutrino models hinted at by MiniBooNE and other data, nor do they probe the $\nu_e$ interpretation of the MiniBooNE excess in a model-independent way. Our analysis code is fully available in https://github.com/Harvard-Neutrino/MicroBooNE-analysis-2021.