Quasi-Elastic Reactions with 600 MeV Protons

A measurement of the (p,2p) differential cross section dσ/dEdΩldΩ2 at 600 MeV on Deuterium and Helium-4 at the NASA Space Radiation Effects Laboratory is reported [1], [2]. Two coincident protons were detected with identical range telescopes. The energy sum of the outgoing protons was constrained to be equal to the incident energy minus the S-state proton separation energy, 2.2 and 20.4 MeV for D and He-4, respectively. By varying the detection angles symmetrically to the beam, events were selected with nuclear recoil momentum \(\vec q_r = \vec p_o - (\vec p_1 + \vec p_2 )\) along the beam line. Values of qr up to 370 MeV/c in D and 300 MeV/c in He-4 were observed.