Positron impact ionization of atomic hydrogen

Triple differential cross sections (TDCS) for the asymmetric geometry have been calculated in a positron-H-atom collision process at intermediate and high incident positron energies. Since the velocity of the ejected electron is small compared with the outgoing positron, direct ionization may be considered to be the only mechanism for ionization. In other words, the probability of ionization through the process of positronium formations to the continuum may be neglected. The TDCS have been computed for different incident positron energies as well as ejected electron energies with different fixed scattering angles of the outgoing positron. In the absence of experimental data, present results are compared with other theoretical predictions and good agreement is noted. (author)