β-decay properties of the ^72,74Co isotopes

It is known that the majority of the heavy elements (Z>26) are formed in neutron capture processes, and the rapid neutron capture (r-) process is responsible for producing approximately half. To fully understand heavy-element nucleosynthesis through the r process, accurate knowledge of nuclear properties is needed. Frequently, nuclear input is not well constrained, and in lieu of data, extrapolations and theoretical models have to be used. Predictions can diverge over orders of magnitude for basic properties far from stability. One of the most important inputs to the r process is β-decay properties. Theory relies on data to constrain their models and make more reliable predictions for experimentally inaccessible nuclei. Measuring β-decay strength functions is a sensitive benchmark to such theoretical models. I will discuss preliminary results on the total absorption spectroscopy of the neutron-rich ^72,74Co isotopes, which is compared to theoretical calculations for the Gamow-Teller strength, B(GT). The measurements were performed at the National Superconducting Cyclotron Laboratory using the SuN detector.