High spin states in 63Cu

Abstract

High-spin states in 63Cu were investigated through in-beam $\gamma$ -ray spectroscopic techniques using the 52Cr(18O, $\alpha$ p2n) fusion-evaporation reaction at a beam energy of 72.5 MeV. The $\gamma$ -rays emitted by the excited nucleus were recorded in the coincidence mode using fourteen Compton suppressed Ge clover detectors of the Indian National Gamma-ray Array (INGA). Based on the $\gamma$ - $\gamma$ coincidence data, twenty-one new $\gamma$ -ray transitions have been observed and placed --thereby extending the level scheme of 63Cu up to spin $25/2\hbar$ and excitation energy $\sim 8.36$ MeV. Shell model calculations are performed in the $f_{5/2}pg_{9/2}$ model space with a 56Ni core using two effective interactions, viz. JUN45 and jj44b to interpret the observed excited states of this nucleus. A reasonable agreement is found between the experimental finding and the shell-model calculations --which implies that the excitations within the $f_{5/2}p_{3/2}p_{1/2}$ orbitals are more dominant in defining the observed level structure than the excitation across the magic shell gap $N = Z = 28$ .