Incident-energy dependence of the analyzing power in the ⁵⁸Ni(p,³He)⁵⁶Co reaction between 80 and 120 MeV

¹ Department of Physics, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa
² iThemba Laboratory for Accelerator Based Sciences, P. O. Box 722, Somerset West 7129, South Africa
³ School of Physics, University of the Witwatersrand, Johannesburg 2050, South Africa

Abstract

This project looks at the angular distributions of the differential cross sections and analyzing powers of a few low lying states of ⁵⁶Co in the reaction ⁵⁸Ni(p,³He)⁵⁶Co at three different incident energies between ⁸⁰and 120 MeV. The measurements are compared with zero-range distorted-wave Born approximation (DWBA) calculations in which we assume a simple direct two-nucleon pickup process. Earlier inclusive (p,³He) reaction studies on similar targets were successfully treated in terms of a statistical pre-equilibrium multistep formalism, in which the final stage of the reaction involved a deuteron pickup, described by means of the DWBA. The analyzing power was shown to be rather sensitive to the contributions of the different order steps. However some features observed in the analyzing powers of these inclusive studies, though reproduced by the theory, are not fully understood.We therefore investigate the ability of the DWBA model to describe the (p,³He) pickup reaction to discrete states at different incident energies using a high resolution spectrometer.