Study of $\mathbf{\beta }$ Decay Shape Factors in First-Forbidden Transitions with $\mathbf{\Delta }{\mathbf{I}}^{\mathbf{\pi }}=0^{-}$ for Reactor Antineutrino Spectra Predictions

Abstract

The electron spectra of the $\beta$ decays of ${}^{92}$Rb and ${}^{142}$Cs, key contributors to the reactor antineutrino spectrum, were measured at the IGISOL facility using radioactive beams of high isotopic purity. The shapes of the measured $\beta$ spectra were compared with various $\beta$ shape models, including first-forbidden correction factors for $\Delta I^{\pi }=0^{-}$ ground-state to ground-state transitions. Comparisons with previous experimental results are also provided. The shapes of the newly measured $\beta$ spectra are well reproduced employing feedings extracted from total absorption gamma spectroscopy measurements.

arXiv comment20 pages, 13 figures

References in corpus (22)

• The Reactor Antineutrino Anomaly
• Improved Predictions of Reactor Antineutrino Spectra
• Search for neutrino oscillations on a long base-line at the CHOOZ nuclear power station
• On the determination of anti-neutrino spectra from nuclear reactors
• Observation of Energy and Baseline Dependent Reactor Antineutrino Disappearance in the RENO Experiment
• Measurement of the Reactor Antineutrino Flux and Spectrum at Daya Bay
• Systematic Uncertainties in the Analysis of the Reactor Neutrino Anomaly
• New antineutrino energy spectra predictions from the summation of beta decay branches of the fission products
• Updated Summation Model: An Improved Agreement with the Daya Bay Antineutrino Fluxes
• Experimental Determination of the Antineutrino Spectrum of the Fission Products of ${}^{238}$U
• High precision analytical description of the allowed $\beta$ spectrum shape
• The Possible Origin and Implications of the Shoulder in Reactor Neutrino Spectra
• First-forbidden transitions in the reactor anomaly
• First-forbidden transitions in the reactor anomaly
• Neutrino Detectors as Tools for Nuclear Security
• Total Absorption Spectroscopy Study of ${}^{92}$Rb Decay: A Major Contributor to Reactor Antineutrino Spectrum Shape
• Reevaluating reactor antineutrino spectra with new measurements of the ratio between ${}^{235}$U and ${}^{239}$Pu $\beta$ spectra
• Stereo neutrino spectrum of 235U fission rejects sterile neutrino hypothesis
• Beta-decay studies for applied and basic nuclear physics
• Comprehensive Measurement of the Reactor Antineutrino Spectrum and Flux at Daya Bay
• First measurements with a new $\beta$-electron detector for spectral shape studies
• Study of beta spectrum shapes relevant to the prediction of reactor antineutrino spectra