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arXiv · 1104.1927

Superallowed Fermi transitions in RPA with a relativistic point-coupling energy functional

Z. X. Li·J. M. Yao·H. Chen
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Abstract

The self-consistent random phase approximation (RPA) approach with the residual interaction derived from a relativistic point-coupling energy functional is applied to evaluate the isospin symmetry-breaking corrections {\delta}c for the 0+\to0+ superallowed Fermi transitions. With these {\delta}c values, together with the available experimental ft values and the improved radiative corrections, the unitarity of the Cabibbo-Kobayashi-Maskawa (CKM) matrix is examined. Even with the consideration of uncertainty, the sum of squared top-row elements has been shown to deviate from the unitarity condition by 0.1% for all the employed relativistic energy functionals.

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Z. X. Li, J. M. Yao, H. Chen. 2011-04-11. Superallowed Fermi transitions in RPA with a relativistic point-coupling energy functional. https://doi.org/10.1007/s11433-011-4320-2

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