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

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Particle-γ coincidence experiments were performed at the Oslo Cyclotron Laboratory with the 181 Ta(d, X) and 181 Ta(3 He, X) reactions to measure the nuclear level densities (NLDs) and γ-ray strength functions (γ SFs) of 180,181,182 Ta using the Oslo method. The back-shifted Fermi-gas, constant temperature plus Fermi gas, and Hartree-Fock-Bogoliubov plus combinatorial models were used for the absolute normalizations of the experimental NLDs at the neutron separation energies. The NLDs and γ SFs are used to calculate the corresponding 181 Ta(n, γ) cross sections and these are compared to results from other techniques. The energy region of the scissors resonance strength is investigated and from the data and comparison to prior work it is concluded that the scissors strength splits into two distinct parts. This splitting may allow for the determination of triaxiality and a γ deformation of 14.9 • ± 1.8 • was determined for 181 Ta.

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