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Title: A Search for Correlated Low-energy Electron Antineutrinos in KamLAND with Gamma-Ray Bursts
Abstract We present the results of a time-coincident event search for low-energy electron antineutrinos in the KamLAND detector with gamma-ray bursts (GRBs) from the Gamma-ray Coordinates Network and Fermi Gamma-ray Burst Monitor. Using a variable coincidence time window of ±500 s plus the duration of each GRB, no statistically significant excess above the background is observed. We place the world’s most stringent 90% confidence level upper limit on the electron antineutrino fluence below 17.5 MeV. Assuming a Fermi–Dirac neutrino energy spectrum from the GRB source, we use the available redshift data to constrain the electron antineutrino luminosity and effective temperature.
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Award ID(s):
2012964 2110720
Publication Date:
Journal Name:
The Astrophysical Journal
Page Range or eLocation-ID:
Sponsoring Org:
National Science Foundation
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