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arXiv · 1612.06004

Shell-model calculation of isospin-symmetry breaking correction to superallowed Fermi beta-decay

L. Xayavong·N. A. Smirnova·M. Bender·K. Bennaceur
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Abstract

We investigate the radial-overlap part of the isospin-symmetry breaking correction to superallowed $0^+\to 0^+$-decay using the shell-model approach similar to that of Refs. [1, 2]. The 8 sd-shell emitters with masses between $A=22$ and $A=38$ have been re-examined. The Fermi matrix element is evaluated with realistic spherical single-particle wave functions, obtained from spherical Woods-Saxon (WS) or Hartree-Fock (HF) potentials, fine-tuned to reproduce the experimental data on charge radii and separation energies for nuclei of interest. The elaborated adjustment procedure removes any sensitivity of the correction to a specific parametrisation of the WS potential or to various versions of the Skyrme interaction. The present results are generally in good agreement with those reported in Refs. [3, 4]. At the same time, we find that the calculations with HF wave functions result in systematically lower values of the correction.

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L. Xayavong, N. A. Smirnova, M. Bender, K. Bennaceur. 2016-12-18. Shell-model calculation of isospin-symmetry breaking correction to superallowed Fermi beta-decay. https://arxiv.org/abs/1612.06004

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