In this Letter, we presented experimental inclusive and exclusive cross sections for the 80Zn(p,2p)79Cureaction and compared them to theoretical single-particle cross sections that were calculated within the distorted-wave impulse approximation (DWIA) . For the ground state, the low-lying pp3/2 state and the knockout of a f7/2 proton, these numbers were to be multiplied by the corresponding spectroscopic factors from the Monte Carlo shell model  to yield the total theoretical cross section. By considering the treatment of two identical protons, the total ( p, p) cross section spp is defined by a differential cross section dspp/dO integrated over the solid angle O and divided by two. The riple differential cross section (TDX) d3sp2p/dE1dO1dO2, where E1 ( O1) is the energy (solid angle) of one outgoing proton and O2 is the solid angle of the other proton, corresponds to dspp/dO specified by the kinematics of the incoming proton and the outgoing protons, taking into account distortion effects, momentum distribution of the nucleon inside a target, and a phase space factor. The ( p,2p) cross section sp2p is then defined by the TDX integrated over E1, O1, and O2, divided by two. Since we counted the number of events in which two protons are detected to evaluate sp2p, the theoretical values that we reported in this Letter should accordingly be divided by two for all single-particle configurations.The DWIA transition matrix was furthermore evaluated with a better numerical accuracy. For the ground state, the low-lying pp3/2 state, and the knockout of a f7/2 proton, the single-particle cross sections become 1.0, 1.3, and 1.1 mb, respectively. They depend only weakly on the excitation energy. Multiplied by the theoretical spectroscopic factors, a total cross section of 9.3 mb can be obtained compared to the measurement of 7.9(4) mb. The result does not affect the conclusions of this Letter, but it shows that there is good agreement between experiment and theory since the amount of correlations that are incorporated in the shell-model calculation and that reduce the theoretical cross section are better taken care of than we found initially.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)