$g_{9/2}$ neutron strength in the $N=29$ isotones and the ${}^{52}$Cr($d,p$)${}^{53}$Cr reaction

Abstract

We performed a measurement of the ${}^{52}$Cr$(d,p{)}^{53}$Cr reaction at 16 MeV using the Florida State University Super-Enge Split-Pole Spectrograph (SE-SPS) and observed 26 states. While all of the states observed here had been seen in previous $(d,p)$ experiments, we changed five $L$ assignments from those reported previously and determined $L$ values for nine states that had not had such assignments made previously. The $g_{9/2}$ neutron strength observed in ${}^{53}$Cr in the present work and in the $N=29$ isotones ${}^{49}$Ca, ${}^{51}$Ti, and ${}^{55}$Fe via $(d,p)$ reactions is much smaller than the sum rule for this strength. Most of the observed $L=4$ strength in these nuclei is located in states near 4 MeV excitation energy. The remaining $g_{9/2}$ strength may be located in the continuum or may be fragmented among many bound states. A covariant density functional theory calculation provides support for the hypothesis that the $g_{9/2}$ neutron orbit is unbound in ${}^{53}$Cr. The ($\hat{I}\pm {,}^3$He) reaction may provide a more sensitive probe for the missing $g_{9/2}$ neutron strength. In addition, particle-${\hat{I}}^3$ coincidence experiments may help resolve some remaining questions in this nucleus.

15 pages, 5 figures. arXiv admin note: text overlap with arXiv:2212.04384