Gamma-Particle Coincidence Studies of ⁹³Sr(d,p)⁹⁴Sr via the Surrogate Reaction Method

Neutron-capture cross sections play a vital role in our understanding of heavy element nucleosynthesis, particularly in astrophysical processes such as the i-process (intermediate) and r-process (rapid). Element formation occurs in these neutron-rich environments and involves short-lived isotopes for which capture cross sections cannot be measured via direct techniques. Reactions rates in these regions instead rely on theoretical calculations that can have uncertainties up to a few orders of magnitude. Previous measurements of the β-decay of ⁹⁴Rb compared the neutron-to gamma-ray-branching ratio of state decays above the neutron separation energy in ⁹⁴Sr and found an enhancement in the γ-ray branch which would in turn lead to an unexpectedly large ⁹³Sr(n,γ) cross section. Such an enhancement could have a strong impact on our understanding of nucleosynthesis processes for nuclei in this region. In order to investigate this potential enhancement of the ⁹³Sr(n,γ) cross section, an experiment was performed at TRIUMF using an 8 MeV/u ⁹³Sr beam impinging on a CD₂ target. The (d,pγ) coincidence data were obtained using the SHARC and TIGRESS arrays. Experimental details from the measurement of ⁹³Sr(d,p)⁹⁴Sr will be presented along with preliminary gamma-particle coincidence analysis using the Surrogate Reaction Method.