CLOSE-COUPLING CALCULATIONS OF POSITRON-HYDROGEN SCATTERING AT LOW ENERGIES

Calculations of low energy positron-hydrogen scattering using the clos e coupling approach are reported at low energies. Calculations are per formed with six and twelve state basis sets which include physical sta tes and pseudostates for both atomic hydrogen and positronium. For ene rgies below the positronium formation threshold, phaseshifts are repor ted for J = 0, 1, 2, 3 and 4 and found to agree with previous variatio nal calculations to better than 0.01 rad. Total elastic and positroniu m formation cross sections are reported at four energies in the Ore ga p. The J = 0, 1 and 2 partial cross sections from the present calculat ions agree with earlier partial cross sections computed using variatio nal techniques.