Configuration Mixing Effects in Magnetic Moments and in Gamow-Teller Matrix Elements of Mirror Nuclei

Phenomenological analysis of Gamow-Teller transitions and magnetic moments is done for the ground states of the mirror nuclei, putting in evidence the linear quenching of the matrix elements $〈\Sigma i^A{\sigma }_{3i}〉$ and $〈\Sigma i^A{\sigma }_{3i}{\tau }_{3i}〉$. Configuration mixing techniques in the $j-j$ coupling scheme are discussed and used to explain the quenching and to fit the experimental data.