Determining Yields of Fragment Pairs from Californium-252 SF Decays

We analyzed data from the spontaneous fission of californium-252 (Cf-252) to determine yields for the fission partner element pairs tellurium(Z=52)/palladium(Z=46) and strontium(Z=38)/neodymium(Z=60). Previously, the case of barium(Z=56)/molybdenum(Z=42) was shown to have unusually high 8, 9, and 10 neutron emissions, (S.-C. Wu et al.) compared to other element partners seen in the spontaneous fission of Cf-252. With updated level schemes and a larger coincidence dataset, we tested the uniqueness of this case (A.H. Thibeault et al.) by analyzing the neutron channels of the two aforementioned element pairs. Via coincidence counting on γ-γ-γ gates, we measured ground state energy transitions of the studied isotopes to determine the relative yields of all visible isotope partner pairs. We placed the yields in a matrix that quantifies how often two specific isotopes of daughter elements appear in the spontaneous fission of Cf-252. We see that, in our studied elements, the higher neutron channel numbers have negligible yields, confirming the uniqueness of the Ba--Mo case, which may indicate a highly energetic, hyperdeformed Ba-144 nucleus at scission.