Structure of ${}^{38}$Cl and the quest for a comprehensive shell model interaction

Abstract

The higher-spin structure of ${}^{38}$Cl ($N=21$) was investigated following the ${}^{26}$Mg(${}^{14}$C, $pn$) reaction at 30 and 37 MeV beam energies. The outgoing protons were detected in an $E-\Delta E$ Si telescope placed at 0${}^{\circ }$ close to the target with a Ta beam stopper between the target and telescope. Multiple $\gamma$ rays were detected in time coincidence with the protons using an enhanced version of the FSU $\gamma$ detection array. The level scheme was extended up to 8420 keV with a likely spin of 10 $\hslash$. A new multishell interaction was developed guided by the experimental information. This FSU interaction was built by fitting to the energies of 270 experimental states from ${}^{13}$C to ${}^{51}$Ti. Calculations using the FSU interaction reproduce observed properties of ${}^{38}$Cl rather well, including the spectroscopic factors. The interaction has been successfully used to interpret the $1p1h$ and $2p2h$ configurations in some nearby nuclei as well.

Comments: Published in https://doi.org/10.1103/PhysRevC.100.034308