Two-quasiparticle states in Bk250 studied by decay scheme and transfer reaction spectroscopy

Two-quasiparticle states in Bk250 were investigated with decay scheme studies and the single-neutron transfer reaction Bk249(d,p)Bk250. Mass-separated sources of Es254 were used for α singles and α-γ coincidence measurements. These studies, plus previous studies of 254Esm α decay and the Bk249(n,γ) reaction, provide spins and parities of the observed levels. The transfer reaction Bk249(d,p)Bk250 was used to deduce neutron single-particle components of the observed bands. Six pairs of singlet and triplet states, formed by the coupling of proton and neutron one-quasiparticle states, were identified. The splitting energies between the triplet and singlet states were found to be in agreement with previous calculations.