Low spin structure of theN=Zodd-odd nucleus2346V23

Abstract

Low spin states in the odd-odd nucleus ${}^{54}\mathrm{Co}$ were investigated with the ${}^{54}\mathrm{Fe}(p,n\ensuremath{\gamma}{)}^{54}\mathrm{Co}$ fusion evaporation reaction at the FN-TANDEM accelerator in Cologne. $\ensuremath{\gamma}\ensuremath{\gamma}$-coincidences, $\ensuremath{\gamma}\ensuremath{\gamma}$-angular correlations, and Compton asymmetries were measured. 28 low spin states were observed. 19 for the first time, eight new spin assignments and six new parity assignments were made, and seven $\ensuremath{\gamma}$-branching ratios were measured for the first time. $M1$ and $E2$ transition strengths between low-lying states in ${}^{54}\mathrm{Co}$ were calculated in the shell-model framework. The experimental branching ratios and multipole mixing ratios indicate the existence of very strong isovector $M1$ transitions.