Search for astrophysical electron antineutrinos in Super-Kamiokande with 0.01wt% gadolinium-loaded water

Abstract

We report the first search result for the flux of astrophysical electron antineutrinos for energies O(10) MeV in the gadolinium-loaded Super-Kamiokande (SK) detector. In June 2020, gadolinium was introduced to the ultra-pure water of the SK detector in order to detect neutrons more efficiently. In this new experimental phase, SK-Gd, we can search for electron antineutrinos via inverse beta decay with efficient background rejection and higher signal efficiency thanks to the high efficiency of the neutron tagging technique. In this paper, we report the result for the initial stage of SK-Gd with a $22.5\times 552$ $\mathrm{kton}\cdot \mathrm{day}$ exposure at 0.01% Gd mass concentration. No significant excess over the expected background in the observed events is found for the neutrino energies below 31.3 MeV. Thus, the flux upper limits are placed at the 90% confidence level. The limits and sensitivities are already comparable with the previous SK result with pure-water ($22.5\times 2970\mathrm{kton}\cdot \mathrm{day}$) owing to the enhanced neutron tagging.

References in corpus (16)

• Calculation of atmospheric neutrino flux using the interaction model calibrated with atmospheric muon data
• The Diffuse Supernova Neutrino Background
• The Diffuse Supernova Neutrino Background is detectable in Super-Kamiokande
• Improvement of low energy atmospheric neutrino flux calculation using the JAM nuclear interaction model
• The NEUT Neutrino Interaction Simulation
• Perturbative Lorentz and CPT violation for neutrino and antineutrino oscillations
• Diffuse Supernova Neutrino Background Search at Super-Kamiokande
• Diffuse neutrino flux from failed supernovae
• Testing MeV dark matter with neutrino detectors
• Spectrum of the Supernova Relic Neutrino Background and Metallicity Evolution of Galaxies
• Reference worldwide model for antineutrinos from reactors
• Limits on astrophysical antineutrinos with the KamLAND experiment
• Impact of binary interactions on the diffuse supernova neutrino background
• Impact of late-time neutrino emission on the diffuse supernova neutrino background
• Exploring the Fate of Stellar Core Collapse with Supernova Relic Neutrinos
• Search for solar electron anti-neutrinos due to spin-flavor precession in the Sun with Super-Kamiokande-IV

Cited by in corpus (22)

• Second gadolinium loading to Super-Kamiokande
• Solar fusion III: New data and theory for hydrogen-burning stars
• Neutrinos from explosive transients at the dawn of multi-messenger astronomy
• Combined Pre-Supernova Alert System with Kamland and Super-Kamiokande
• Diffuse Neutrino Flux Based on the Rates of Core-collapse Supernovae and Black Hole Formation Deduced from a Novel Galactic Chemical Evolution Model
• Probing self-interacting sterile neutrino dark matter with the diffuse supernova neutrino background
• Diffuse supernova neutrino background with up-to-date star formation rate measurements and long-term multidimensional supernova simulations
• Neutrinos from Earth-Bound Dark Matter Annihilation
• Stellar Neutrino Emission Across The Mass-Metallicity Plane
• Nuclear deexcitation simulator for neutrino interactions and nucleon decays of ${}^{12}\text{C}$ and ${}^{16}\text{O}$ based on TALYS
• Detectability of Late-time Supernova Neutrinos with Fallback Accretion onto Protoneutron star
• Distinctive nuclear signatures of low-energy atmospheric neutrinos
• Implementation and investigation of electron-nucleus scattering in the \textsc{NEUT} neutrino event generator
• Diffuse Neutrino Background from Magnetorotational Stellar Core Collapses
• First Detailed Calculation of Atmospheric Neutrino Foregrounds to the Diffuse Supernova Neutrino Background in Super-Kamiokande
• Impacts of Black-Hole-Forming Supernova Explosions on the Diffuse Neutrino Background
• Measurement of $\gamma$-rays generated by neutron interaction with ${}^{16}$O at 30 MeV and 250 MeV
• Towards Multi Energy Neutrino Astronomy: Diagnosing Enhanced Circumstellar Material around Stripped-Envelope Supernovae
• Modification on thermal motion in Geant4 for neutron capture simulation in Gadolinium loaded water
• Water-based Quantum Dots Liquid Scintillator for Particle Physics
• Benchmarks and applications of the nuclear deexcitation event generator NucDeEx
• Neutron multiplicity measurement in muon capture on oxygen nuclei in the Gd-loaded Super-Kamiokande detector