Limits on Astrophysical Antineutrinos with the KamLAND Experiment
Name
Abe_2022_ApJ_925_14.pdf
Description
Published version
Size
1.19 MB
Format
Adobe PDF
Checksum (MD5)
8d5b688ad44e5ee43a130fda172d1d80
Author(s)
Axani, Spencer Nicholas
Winslow, Lindley
Fu, Z.
Ouellet, Jonathan L
Date Issued
January 1, 2022
Journal
The Astrophysical Journal
Publisher
American Astronomical Society
Citation
Winslow, Lindley. 2022. "Limits on Astrophysical Antineutrinos with the KamLAND Experiment." The Astrophysical Journal, 925 (1).
Version
Final published version
Abstract
We report on a search for electron antineutrinos (${\bar{\nu }}_{e}$) from astrophysical sources in the neutrino energy range 8.3–30.8 MeV with the KamLAND detector. In an exposure of 6.72 kton-year of the liquid scintillator, we observe 18 candidate events via the inverse beta decay reaction. Although there is a large background uncertainty from neutral current atmospheric neutrino interactions, we find no significant excess over background model predictions. Assuming several supernova relic neutrino spectra, we give upper flux limits of 60–110 cm−2 s−1 (90% confidence level, CL) in the analysis range and present a model-independent flux. We also set limits on the annihilation rates for light dark matter pairs to neutrino pairs. These data improve on the upper probability limit of 8B solar neutrinos converting into ${\bar{\nu }}_{e}$, ${P}_{{\nu }_{e}\to {\bar{\nu }}_{e}}\lt 3.5\times {10}^{-5}$ (90% CL) assuming an undistorted ${\bar{\nu }}_{e}$ shape. This corresponds to a solar ${\bar{\nu }}_{e}$ flux of 60 cm−2 s−1 (90% CL) in the analysis energy range.
MIT Department
Massachusetts Institute of Technology. Department of Physics
Terms of Use
Creative Commons Attribution 4.0 International License
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.3847/1538-4357/ac32c1
