2021/01/31 by Anil Kumar, Praveen C. Srivastava, Jouni Suhonen
Physics and Astronomy · #Computation #Coupling (piping) #Electron #Matrix (chemical analysis) #Measure (data warehouse) #Neutrino Physics Research #Nuclear physics research studies #Quantum Chromodynamics and Particle Interactions #Space (punctuation) #Spectral line #nucl-th
paper · pdf · doi:10.1140/epja/s10050-021-00540-6
published as Eur. Phys. J. A 57, 225 (2021) · 18 pages, 10 figures and 6 tables. Accepted for publication in the European Physical Journal A
arxiv created 2021/06/29 · openalex publication_date 2021/07/01 · openalex created_date 2021/07/05 · arxiv updated 2021/07/13 · openalex updated_date 2026/08/05
In this work, we present a theoretical study of the electron spectral shapes for the second-forbidden nonunique β--decay transitions 59\textrmFe(3/2-)→ 59\textrmCo(7/2-) and 60\textrmFe(0+)→ 60\textrmCo(2+) in the framework of the nuclear shell model. We have computed the involved wave functions by carrying out a complete 0ℏω calculation in the full fp model space using the KB3G and GXPF1A effective interactions. When compared with the available data, these interactions predict the low-energy spectra and electromagnetic properties of the involved nuclei quite successfully. This success paves the way for the computations of the β-decay properties, and comparison with the available data. We have computed the electron spectral shapes of the mentioned decay transitions as functions of the value of the weak axial coupling g\rm A. By comparing these computed shapes with the measured spectral shapes allows then to extract the effective value of g\rm A for these decay transitions. This procedure, coined the spectrum-shape method (SSM) in several earlier studies, complements the method of determining the value of g\rm A by reproducing the (partial) half-lives of decay transitions. Here we have enhanced the original SSM by constraining the value of the relativistic vector matrix element, VM(0)KK-11, using the conserved vector-current hypothesis (CVC) as a starting point. We hope that this finding would be a strong incentive to measure the spectral shapes in the future.