On the theoretical and experimental cross sections for low-energy positron-rare-gas scattering

Abstract

It is argued that the momentum transfer cross sections for positron-neon scattering of McEachran et al. (1979) and for positron-argon scattering of Montgomery and LaBahr (1970) are too low in the Ramsauer minimum energy region on the grounds of positron lifetime studies. It is then shown that at these energies the corresponding theoretical elastic cross sections, which agree with the experimental total cross sections of Kauppila et al. (1976, 1977) are also too low. This conclusion supports the suggestion of Humberston (1978) that the experiment of Kauppila et al. neglects small-angle scattering.