Energy-Sharing Asymmetries in Ionization by 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...

Electron-impact ionization of helium for equal-energy-sharing kinematics

The close-coupling approach to electron-helium single ionization is analyzed and several ways of defining the scattering amplitudes are determined, for both equaland unequal-energy outgoing electrons. Nevertheless, the various definitions all lead to the same cross section. The convergent close-coupling sCCCd method with Laguerre sCCC-Ld and box-based sCCC-Bd target functions is applied to calc...

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

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...

Ionization by impact electrons in solids: Electron mean free path fitted over a wide energy range

We propose a simple formula for fitting the electron ionization mean free paths in solids both at high and at low electron energies. The free-electron-gas approximation used for predicting electron mean free paths is no longer valid at low impact energies E−EF 50 eV , as the band structure effects become significant at those energies. Therefore, we include the results of band structure calculat...