Differential ionization studies by positron impact

K-shell ionization of atoms by electron and positron impact.

Energy-sharing asymmetries in ionization by positron impact.

The triply differential cross section of molecular hydrogen for ionization by 50 eV positrons has been determined, for the first time, for both the ejected electron in coincidence with the remnant ion and for the scattered projectile. Asymmetries in the energy sharing between the two light particles in the final state are observed, with the electron spectrum being shifted to significantly lower...

Ionization of K-shell electrons by electron or positron impact

The single ionization of inner-shell electrons by electron or positron impact are the fundamental processes, which still attract considerable interest in collision theory, experimental studies, and various applications. To predict the ionization cross sections, one usually employs either sophisticated numerical approaches or empirical and semiempirical formulas. Significant efforts have been al...

Impact parametermethod calculations for fully differential ionization cross sections

In this work our previous fully differential ionization cross section calculations using the semiclassical, impact parameter method are improved by a new method suitable to calculate impact parameter values corresponding to different momentum transfers. This goal is achieved by two successive steps. First, using the transverse momentum balance different projectile scattering angles are calculat...

Excitation of molecular vibrations by positron impact.

Absolute cross sections for the vibrational excitation of CO, CO2, and H2 by positron impact are presented for incident positron energies from 0.5 eV to several electron volts. The measurements use a novel technique that exploits the adiabatic motion of a positron beam in a strong magnetic field. This work is the first systematic experimental study of vibrational excitation by positron impact, ...