Mirror energy differences between 43Ti and 43Sc: A direct insight into the nuclear wave functions

The structure of the 2243Ti21 nucleus has been explored employing correlations between delayed and prompt γ rays, leading to a substantial extension of its positive-parity yrast band up to 25/2+. New states were were identified using the isomer-tagging technique together with γ−γ coincidences and were compared to the analogue states in the mirror nucleus 2143Sc22. The Mirror Energy Differences (MED) between analogue states have been extracted and compared to the predictions from the Large-Scale Shell-Model calculations in two main shells. For the positive-parity states which involve particle-hole excitations from the sd to the fp shell, a striking correlation between the measured MED and the type of nucleons excited across the shell gap is observed. This is reinforced by the systematic behavior of non-natural parity MED for nuclei across the entire f 7/2 shell, which puts in evidence that experimental MED serve as direct, sensitive probes of the underlying microscopic structure of nuclear wave function.