Momentum-space treatment of the Coulomb interaction in three-nucleon reactions with two protons

Abstract

The Coulomb interaction between two protons is included in the calculation of proton-deuteron elastic scattering, radiative proton-deuteron capture, and two-body electromagnetic disintegration of 3He. The hadron dynamics is based on the purely nucleonic charge-dependent (CD) Bonn potential and its realistic extension CD Bonn +Δ to a coupled-channel two-baryon potential, allowing for single virtual Δ-isobar excitation. Calculations are done using integral equations in momentum space. The screening and renormalization approach is employed for including the Coulomb interaction. Convergence of the procedure is found at moderate screening radii. The reliability of the method is demonstrated. The Coulomb effect on observables is seen at low energies for the entire kinematic regime. In proton-deuteron elastic scattering at higher energies the Coulomb effect is confined to forward scattering angles; the Δ-isobar effect found previously remains unchanged by the Coulomb effect. In electromagnetic reactions the Coulomb effect competes with other effects in a complicated way.