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arXiv · 1101.0939

Microscopic calculations of isospin-breaking corrections to superallowed beta-decay

W. Satula·J. Dobaczewski·W. Nazarewicz·M. Rafalski
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Abstract

The superallowed beta-decay rates that provide stringent constraints on physics beyond the Standard Model of particle physics are affected by nuclear structure effects through isospin-breaking corrections. The self-consistent isospin- and angular-momentum-projected nuclear density functional theory is used for the first time to compute those corrections for a number of Fermi transitions in nuclei from A=10 to A=74. The resulting leading element of the CKM matrix, |V_{ud}|= 0.97447(23), agrees well with the recent result by Towner and Hardy [Phys. Rev. C {\bf 77}, 025501 (2008)].

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W. Satula, J. Dobaczewski, W. Nazarewicz, M. Rafalski. 2011-03-09. Microscopic calculations of isospin-breaking corrections to superallowed beta-decay. https://doi.org/10.1103/physrevlett.106.132502

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