Isospin mixing inIn111and the inclusion of additional terms in the mixing formalism

Abstract

The extent of isospin mixing in $^{111}\mathrm{In}$ has been determined at 20.9 MeV on the basis of measured cross sections for the ($p, {p}^{\ensuremath{'}}$), ($p, \ensuremath{\alpha}$), ($\ensuremath{\alpha}, p$) and ($\ensuremath{\alpha}, {\ensuremath{\alpha}}^{\ensuremath{'}}$) reactions involving the formation of the $^{111}\mathrm{In}$ compound nucleus. The following values were obtained for the mixing fraction and the isospin mixing matrix element: $\ensuremath{\mu}=0.62\ifmmode\pm\else\textpm\fi{}0.14$ and $|{H}_{c}|=0.013\ifmmode\pm\else\textpm\fi{}0.004$ eV. These results are based on a reformulation of the isospin mixing theory in which additional terms are included. Previous data available for the $A\ensuremath{\sim}50\ensuremath{-}70$ region are reanalyzed using this formalism and the dependence of $|{H}_{c}|$ on energy, mass number, and the probability of proton emission from the ${T}_{<}(\mathrm{nonanalog})$ states of the compound nucleus is determined. $|{H}_{c}|$ varies inversely with the first two of these quantities and directly with the third.NUCLEAR REACTIONS $^{110}\mathrm{Cd}(p, {p}^{\ensuremath{'}})$ and ($p, \ensuremath{\alpha}$) ${E}_{p}=16.0$ $^{107}\mathrm{Ag}(\ensuremath{\alpha}, {\ensuremath{\alpha}}^{\ensuremath{'}})$ MeV; $^{107}\mathrm{Ag}(\ensuremath{\alpha}, {\ensuremath{\alpha}}^{\ensuremath{'}})$ and ($\ensuremath{\alpha}, p$), ${E}_{\ensuremath{\alpha}}=19.58$ MeV; measured differential cross sections at 30\ifmmode^\circ\else\textdegree\fi{}-150\ifmmode^\circ\else\textdegree\fi{}; deduced isospin mixing fraction and mixing matrix element. Theory of isospin mixing reformulated to include additional terms.