Radiative strength of neutron-rich strontium isotopes*

Our understanding of neutron-induced reactions on nuclei far from stability has far reaching implications for cosmogenic nucleosynthesis and fundamental nuclear physics. Direct measurement of the radiative-capture cross section is experimentally inaccessible for these short-lived nuclei; however, indirect methods such as the β-Oslo Method enable the experimental constraint of key nuclear properties that are inputs for reaction-theory calculations.

An experiment to determine the γ-ray strength function (γSF) and nuclear level density (NLD) for ^93,94,95Sr isotopes using high-intensity Californium Rare Isotope Breeder Upgrade (CARIBU) beams is being performed at Argonne National Laboratory (ANL). The γSF and NLD, properties extracted from the measured γ-ray spectra using the β-Oslo Method, contribute the greatest uncertainty in Hauser-Feshbach calculations of neutron-capture reaction rates for short-lived neutron-rich nuclei. The experimental techniques and preliminary results of this work will be presented. Furthermore, the results of this work will shed light on nuclear structure properties for Sr isotopes, leading to significantly improved predictive reaction modeling.