Determination of Beta Decay Ground State Feeding of Nuclei of Importance for Reactor Applications

Abstract

In $\beta$-decay studies the determination of the decay probability to the ground state of the daughter nucleus often suffers from large systematic errors. The difficulty of the measurement is related to the absence of associated delayed $\gamma$-ray emission. In this work we revisit the $4\pi \gamma -\beta$ method proposed by Greenwood and collaborators in the 1990s, which has the potential to overcome some of the experimental difficulties. Our interest is driven by the need to determine accurately the $\beta$-intensity distributions of fission products that contribute significantly to the reactor decay heat and to the antineutrinos emitted by reactors. A number of such decays have large ground state branches. The method is relevant for nuclear structure studies as well. Pertinent formulae are revised and extended to the special case of $\beta$-delayed neutron emitters, and the robustness of the method is demonstrated with synthetic data. We apply it to a number of measured decays that serve as test cases and discuss the features of the method. Finally, we obtain ground state feeding intensities with reduced uncertainty for four relevant decays that will allow future improvements in antineutrino spectrum and decay heat calculations using the summation method.

References in corpus (19)

• Observation of Reactor Electron Antineutrino Disappearance in the RENO Experiment
• The Reactor Antineutrino Anomaly
• Indication for the disappearance of reactor electron antineutrinos in the Double Chooz experiment
• Improved Predictions of Reactor Antineutrino Spectra
• On the determination of anti-neutrino spectra from nuclear reactors
• Measurement of the Reactor Antineutrino Flux and Spectrum at Daya Bay
• Updated Summation Model: An Improved Agreement with the Daya Bay Antineutrino Fluxes
• The Possible Origin and Implications of the Shoulder in Reactor Neutrino Spectra
• Total Absorption Spectroscopy Study of ${}^{92}$Rb Decay: A Major Contributor to Reactor Antineutrino Spectrum Shape
• Neutrino Oscillation Studies with Reactors
• Total Absorption Gamma-Ray Spectroscopy of 87Br, 88Br and 94Rb Beta-Delayed Neutron Emitters
• Total Absorption Spectroscopy Study of the Beta Decay of ${}^{86}$Br and ${}^{91}$Rb
• Revealing Fine Structure in the Antineutrino Spectra From a Nuclear Reactor
• Characterization and performance of the DTAS detector
• Total absorption $\gamma$-ray spectroscopy of niobium isomers
• A GEANT4 Monte-Carlo Simulation Code for precision beta spectroscopy
• Study of the $\beta$-decay of ${}^{100}$Tc with Total Absorption $\gamma$-Ray Spectroscopy
• Total absorption $\gamma$-ray spectroscopy of the $\beta$-delayed neutron emitters ${}^{137}$I and ${}^{95}$Rb
• Characterization of a cylindrical plastic β-detector with Monte Carlo simulations of optical photons

Cited by in corpus (3)

• Reactor antineutrino flux and anomaly
• Mapping reactor neutrino spectra from TAO to JUNO
• Study of beta spectrum shapes relevant to the prediction of reactor antineutrino spectra