High resolution 148Nd(3He,nγ) two proton stripping reaction and the structure of the 02+ state in 150Sm

The challenge of achieving high resolution in binary reactions involving an outgoing high energy neutron is solved by detecting the γ-ray decay of populated excited states in an array of escape suppressed HPGe detectors in coincidence with fast neutrons detected in a wall of scintillator detectors 2m down beam of the target. The selectivity of the arrangement is of the order of 1 in 1000. The time-of-flight difference is sufficient to separate fast neutrons from direct reactions from a large background of statistical neutrons from fusion-evaporation reactions. Our interest is in the wavefunction of the 02+ state at 740 keV in the N=88 nucleus 150Sm which, with the 02+ state in 100Ru, are the only two excited states observed in 2β2ν double β-decay.