Intruder states in A=53-57 nuclei and configurational purity in54Mn

Abstract

Calculations with an effective interaction largely determined by least-squares fits to energy levels of A=48-56 nuclei successfully reproduce the observed excitation energies of many 'intruder states' in this mass region. Detailed results are given for 54Mn, which appears to have low-lying intruder states of very pure configurational structure.