P+D-]P+P+N REACTION AT 6.5[=EP[=13-MEV

The D(p,2p) n reaction was studied in a kinematically complete experiment at proton bombarding energies of 6.5-13.0 MeV. Silicon surface-barrier detectors were used to record coincident proton-energy spectra at the two sets of angles θ1=30, θ2=30 and θ1=30, θ2=θp, where θ1 and θ2 are on opposite sides of the beam axis and θp is the proton angle corresponding to an n-p system with low relative energy recoiling at θ1=30. The spectra at θ1=30, θ2=30 were dominated by the direct knockout or quasifree mechanism and the spectra at θ1=30, θ2=θp were dominated by the two-step sequential decay mechanism p+D→p+d*→p+p+n, where d* is a short-lived particle composed of a neutron and a proton in a S01 configuration. The Kuckes-Wilson-Cooper form of the spectator-model calculation gives a good qualitative fit to the knockout data. A least-squares fit of three forms of the density-of-states function to the Ep=11 MeV, θ1=30, θp=77 data gave the best result with the renormalized density-of-states function. Including the statistically most significant, independently measured spectra at bombarding energies of 9, 11, 12, and 13 MeV, a neutron-proton singlet scattering length of -23.9±0.8 fm is obtained. © 1969 The American Physical Society.