Six-state algebraic close-coupling calculation of positron-hydrogen scattering at low energies

We did the Harris-Nesbet algebraic close-coupling calculation for positron-hydrogen scattering at low energies with the (1s,2s)H-(1s,2s)Ps, (1s,2s,2p)H-(1s,2s)Ps, and (1s,2s,2p)H-(1s,2s,2p)Ps coupling schemes. Cross sections of elastic scattering, positronium formation, and Ps(1s)-p elastic scattering were obtained for L=0,1,2,3,4,5,6 partial waves. The integrated cross sections for the relevant processes were then estimated. We compared our six-state close-coupling results with the ones calculated by solving the Lippmann-Schwinger coupled equations in momentum space. Many special features were seen in these cross sections.