Resolution of complex γ spectra from triple-coincidence data: Ba–Mo split in 252Cf spontaneous fission

Using triple-coincidence events of prompt fission γ rays from spontaneous fission of 252Cf, we made a new analysis of the yield matrix of coincident pairs of barium (Z=56) and molybdenum (Z=42) fission fragments. Branching from γ-bands (K=2) and octupole-bands (K=0) were also measured. From this reanalysis the previously proposed “extra-hot-fission mode” (8–10 neutrons evaporated) is much weaker than first reported. In this paper, we discuss in detail the methodology, including background subtraction for triple-coincidence data. The importance of minimal compression spectra allowing least-squares peak-fitting analysis is emphasized.