High-resolution ( p,t ) reaction measurements as spectroscopic tests of ab-initio theory in the mid- pf shell

Abstract

Detailed spectroscopic measurements of excited states in 50 Cr and 62 Zn were performed using 24 MeV (p,t) transfer reactions on 52 Cr and 64 Zn, respectively. In total, forty-five states in 50 Cr and sixty-seven states in 62 Zn were observed up to excitation energies of 5.5 MeV, including several previously unobserved states. These experimental results are compared to ab-initio shell-model calculations using chiral effective field theory (χ-EFT) with the valence-space in-medium similarity renormalization group (VS-IMSRG) method. This comparison demonstrates good agreement in the level orderings with these new theoretical methods, albeit with a slight over binding in the calculations. This work is part of a continued push to benchmark ab-initio theoretical techniques to nuclear structure data in 0 + → 0 + superallowed Fermi β decay systems.