Étude de la structure des noyaux légers par les réactions (p, 2p) à 155 MeV

Abstract

Resume We have studied summed energy spectra displayed by protons emitted in coincidence in (p, 2p) reactions induced by 155 MeV incident protons on the following target nuclei: Li 6 , Li 7 , B 10 , B 11 and C 12 . Two telescopes each with 2 plastic scintillators and 1 NaI total absorption scintillator were used to detect the product protons. The summed energy spectra exhibit generally 2 well defined peaks which define the binding energy. Angular correlation distributions were obtained for those events under each summed energy peak for which the 2 product protons are emitted in a plane symmetrically on each side of the incident beam and have approximately the same energy. Applying the Born approximation and neglecting nuclear absorption, we have deduced momentum density distributions for protons in the target nuclei. The high binding energy proton distribution presents a maximum for zero momentum, characteristic of an s state, the lower-binding energy proton distribution presents a minimum for zero momentum, characteristic of a p state, except in the case of Li 6 . Parameters of these distributions are given which permit comparison among the various target nuclei.