Positron--hydrogen scattering for energies up to the n = 2 threshold of hydrogen

Some $s$-wave scattering parameters are calculated using a close-coupling wave function similar to that of Drachman's but with the explicit addition of the positronium channel and its polarization. The elastic phase shifts are in close agreement with those of Bhatia et al. and the inelastic $R$-matrix diagonal elements show a better phase-shift bound than previous calculations.