Nuclear level densities and ${\hat{I}}^3$-ray strength functions of ${}^{87}\mathrm{Kr}$ -- First application of the Oslo Method in inverse kinematics

Abstract

The ${\hat{I}}^3$-ray strength function (${\hat{I}}^3$SF) and nuclear level density (NLD) have been extracted for the first time from inverse kinematic reactions with the Oslo Method. This novel technique allows measurements of these properties across a wide range of previously inaccessible nuclei. Proton-${\hat{I}}^3$ coincidence events from the $\mathrm{d}{(}^{86}\mathrm{Kr},\mathrm{p}{\hat{I}}^3{)}^{87}\mathrm{Kr}$ reaction were measured at iThemba LABS and the ${\hat{I}}^3$SF and NLD in ${}^{87}\mathrm{Kr}$ obtained. The low-energy region of the ${\hat{I}}^3$SF is compared to Shell Model calculations which suggest this region to be dominated by M1 strength. The ${\hat{I}}^3$SF and NLD are used as input parameters to Hauser-Feshbach calculations to constrain $(\mathrm{n},{\hat{I}}^3)$ cross sections of nuclei using the TALYS reaction code. These results are compared to ${}^{86}\mathrm{Kr}(n,{\hat{I}}^3)$ data from direct measurements.

Submitted to EpJ A Letters