Coupled-Discretized-Continuum-Channels Method for Deuteron Breakup Reactions Based on Three-Body Model: Justification of the Method for Truncation and Discretization of the p-n Continuum

Abstract

For the treatment of the deuteron breakup process, the p-n continuum states are truncated for linear and angular momenta as k≤kmax and l≤lmax, respectively, and a finite number of p-n breakup channels are introduced by discretizing the p-n continuum into momentum bins with a common width Δk. Validity and usefulness of this method are shown through crucial examinations on the d + 58Ni system at the deuteron incident energy of 80 MeV. The S-matrix elements converge smoothly and rapidly with respect to narrowing Δk in the cases both of the exact Hamiltonian and the adiabatic Hamiltonian. In the latter case, it is explicitly shown that the converged S-matrix elements agree with the exact ones. Sufficient convergence of the breakup S-matrix elements is seen at Δk = 1/8 fm-1 and that of the elastic ones at Δk = 1/4 fm-1. The S-matrix elements also converge quickly with respect to increasing kmax and lmax. Physically sufficient truncation is given by kmax∼1.0 fm-1 and lmax = 2.