Extracting interaction parameters from near threshold positron experiments

P. A. MACRI; R. O. BARRACHINA

Nuclear Instruments and Methods in Physics Research Section B

Elsevier

Lugar: Amsterdam; Año: 2009 vol. 267 p. 254 - 256

0168-583X

We analyze different methods to extract, from experiments, positron-atom interaction parameters such as the scattering length and the effective range. The near-threshold distributions of positrons in positronium formation or elastic scattering have in common an s-wave evolution in an effective polarization potential. Di®erent generalizations of the effective range theory are used in the literature to fit the experimental data. In this work, we propose a different approach that provides a signifficant improvement over other methods on a much broader range of energies. We discuss the applicability of this method for extracting information on low-energy electron-atom interactions in the case of positronium formation and elastic collisions involving positrons.