First application of the Oslo method in inverse kinematics

The $$\gamma $$-ray strength function ($$\gamma $$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–$$\gamma $$ coincidence events from the $$\mathrm {d}(^{86}\mathrm {Kr}, \mathrm {p}\gamma )^{87}\mathrm {Kr}$$ reaction were measured at iThemba LABS and the $$\gamma $$SF and NLD in $$^{87}\mathrm {Kr}$$ was obtained. The low-energy region of the $$\gamma $$SF is compared to shell-model calculations, which suggest this region to be dominated by M1 strength. The $$\gamma $$SF and NLD are used as input parameters to Hauser–Feshbach calculations to constrain $$(\mathrm {n},\gamma )$$ cross sections of nuclei using the TALYS reaction code. These results are compared to $$^{86}\mathrm {Kr}(n,\gamma )$$ data from direct measurements.