Sensitivity studies for the weak r-process: Beta-decay rates

The rapid neutron capture process (r-process) is a mechanism responsible for manufacturing the heaviest elements (A > 70) in very neutron-rich astrophysical environments. Binary neutron star mergers (NSMs) are favorable candidates for r-process production based on recent multimessenger observations, though it is still an open question whether NSMs are the only site of the r-process or one of many. The elemental abundances of metal-poor stars provide an independent probe of the r-process, and these show a robust pattern of heavier elements with greater dispersion in the weak r-process region (70 < A < 120). This suggests the weak r-process offers key evidence to understand the diversity of r-process sources. With the assistance of nuclear facilities such as FRIB, new experimental data can help constrain the conditions and environments associated with theoretical models that best fit the weak r-process region. Here we describe sensitivity studies of unmeasured beta-decay halflives under a variety of astrophysical conditions to understand which species are most crucial to measure in upcoming experimental campaigns.