  The positron-hydrogen atom scattering system is considered within the S-wave
model. Convergence in the elastic scattering, excitation, ionization, and
positronium formation channels is studied as a function of the number and type
of states used to expand the total wave function. It is found that all
unphysical resonances disappear only if near-complete pseudostate expansions
are applied to both the atomic and positronium centers.
