Inclusive (p, α) and (p,³He) cross sections induced by 100 MeV protons on ⁴⁰Ca

Abstract

Alpha clusteri ng in nuclei is studied with quasi - free knockout reactions. A beam of 100 MeV polarized protons was used in the quasi-free knockout reaction 40 ~a( p,p' a)36 Arat iThemba LABS. While the scattered protons were detected in the K600 magnetic spectrometer, the alpha particles were measured with a detector telescope consisting of three silicon surface barrier detectors. Both coinc idence and pre-scaled singles events were recorded to extract cross sections as well as analysing powers. The inclusive spectra of 40 Ca(p, a) and 4° Ca(p,3 He) were extracted from the prescaled-s ingles data. The prescaled single events were analyzed in order to test the efficiency of the silicon detector telescope and to obtain the double differential cross sections of the emitted 3He and 4 He particles.