P. Navratil et al., LARGE-BASIS SHELL-MODEL CALCULATION OF THE C-10-]B-10 FERMI MATRIX ELEMENT, Physical review. C. Nuclear physics, 56(5), 1997, pp. 2542-2548
We use a 4 (H) over bar Omega shell-model calculation with a two-body
effective interaction derived microscopically from the Reid93 potentia
l to calculate the isospin-mixing correction for the C-10-->B-10 super
allowed Fermi transition. The effective interaction takes into account
the Coulomb potential as well as the charge dependence of T=1 partial
waves. Our results suggest the isospin-mixing correction delta(c) app
roximate to 0.1%, which is compatible with previous calculations. The
correction obtained in those calculations, performed in a Oh Omega spa
ce, was dominated by deviation from unity of the radial overlap betwee
n the converted proton and the corresponding neutron. In the present c
alculation this effect is accommodated by the large model space. The o
btained delta(c) correction is about a factor of 4 too small to obtain
unitarity of the Cabibbo-Kobayashi-Maskawa matrix with the present ex
perimental data.