Studying the β-decay of Exotic Bromine Nuclei

This work presents the extraction of β-decay feeding intensity from the decay of the neutron-rich isotope ⁸⁹Br to ⁸⁹Kr. Using the Californium Rare Isotope Breeder Upgrade (CARIBU) at Argonne National Lab, A=89 isobars were implanted on the tape-transport-system at the center of the Summing NaI(Tl) (SuN) detector. The data was processed to isolate the ⁸⁹Br to ⁸⁹Kr decay events, utilizing time-coincidence techniques and total absorption spectroscopy (TAS) to determine half-lives at certain γ-ray energies and excitation levels. Monte Carlo simulations of γ-ray cascades and radiation transport simulations were employed to extract the β-decay feeding intensity distribution. This measurement provides sensitive constraints to theoretical models used to predict β-decay properties far from stability for astrophysical applications.