INSTITUTO DE INVESTIGACIONES FISICAS DE MAR DEL PLATA
Unidad Ejecutora - UE
Dynamics of collisions with positrons
J. FIOL; P. A. MACRI; R. O. BARRACHINA
Nuclear Instruments and Methods in Physics Research Section B
Lugar: Amsterdam; Año: 2008
The measurement of ionization by positron impact reveals that the maximum of the electron capture to the continuum cusp is shifted from its theoretical position. In this work the hypothesis that the observed effect is the result of an anisotropic momentum distribution in the projectile-electron reference system is considered. By elaborating on the ansatz that the cusp asymmetry is qualitatively similar for positron impact than the for for ion-atom collisions, we obtain fully differential cross sections that show the same features than those experimentally observed. The present estimation for the position of the maximum agrees well with cross section measurements performed in coincident electron-positron detection experiments.