Abstract
We report a search for an anomalous excess of inclusive charged-current (CC) νe interactions using the Wire-Cell event reconstruction package in the MicroBooNE experiment, which is motivated by the previous observation of a low-energy excess (LEE) of electromagnetic events from the MiniBooNE experiment. With a single liquid argon time projection chamber detector, the measurements of νμ CC interactions as well as π0 interactions are used to constrain signal and background predictions of νe CC interactions. A data set collected from February 2016 to July 2018 corresponding to an exposure of 6.369×1020 protons on target from the Booster Neutrino Beam at FNAL is analyzed. With x representing an overall normalization factor and referred to as the LEE strength parameter, we select 56 fully contained νe CC candidates while expecting 69.6±8.0 (stat.) ±5.0 (sys.) and 103.8±9.0 (stat.) ±7.4 (sys.) candidates after constraints for the absence (eLEEx=0) of the median signal strength derived from the MiniBooNE observation and the presence (eLEEx=1) of that signal strength, respectively. Under a nested hypothesis test using both rate and shape information in all available channels, the best-fit x is determined to be 0 (eLEEx=0) with a 95.5% confidence level upper limit of x at 0.502. Under a simple-vs-simple hypotheses test, the eLEEx=1 hypothesis is rejected at 3.75σ, while the eLEEx=0 hypothesis is shown to be consistent with the observation at 0.45σ. In the context of the eLEE model, the estimated 68.3% confidence interval of the νe CC hypothesis to explain the LEE observed in the MiniBooNE experiment is disfavored at a significance level of more than 2.6σ (3.0σ) considering MiniBooNE's full (statistical) uncertainties.
| Original language | English (US) |
|---|---|
| Article number | 112005 |
| Journal | Physical Review D |
| Volume | 105 |
| Issue number | 11 |
| DOIs | |
| State | Published - Jun 1 2022 |
Bibliographical note
Funding Information:This document was prepared by the MicroBooNE Collaboration using the resources of the Fermi National Accelerator Laboratory (Fermilab), a U.S. Department of Energy, Office of Science, HEP User Facility. Fermilab is managed by Fermi Research Alliance, LLC (FRA), acting under Contract No. DE-AC02-07CH11359. MicroBooNE is supported by the following: the U.S. Department of Energy, Office of Science, Offices of High Energy Physics and Nuclear Physics; the U.S. National Science Foundation; the Swiss National Science Foundation; the Science and Technology Facilities Council (STFC), part of the United Kingdom Research and Innovation; the Royal Society (United Kingdom); and The European Union’s Horizon 2020 Marie Skłodowska-Curie Actions. Additional support for the laser calibration system and cosmic-ray tagger was provided by the Albert Einstein Center for Fundamental Physics, Bern, Switzerland. We also acknowledge the contributions of technical and scientific staff to the design, construction, and operation of the MicroBooNE detector as well as the contributions of past collaborators to the development of MicroBooNE analyses, without whom this work would not have been possible.
Publisher Copyright:
© 2022 authors. Published by the American Physical Society. Funded by SCOAP3.