On mechanisms of the direct knock-out reaction of proton pairs from the carbon nucleus by 660 MeV protons

A three-arm spark spectrometer has been used to measure differential cross sections, energy spectra of secondary protons and momentum spectra of residual nuclei for the reaction (p,3p) on the 12C nucleus at 660 MeV in three experimental geometries. Preliminary data were obtained in the fourth geometry at 350 MeV. In all geometries the contribution of mechanism with production of a π0-meson, followed by its capture by the nuclear proton is practically excluded. 8 refs.; 5 figs.; 1 tab