In a recent paper [1], Talukder proposed a new empirical formula for electron-impact ionization cross sections of He-like ions that was claimed to excellently agree with the available experimental and theoretical data. Discussing this agreement, the author of reference [1] makes extensive comparison with our recommended formula of reference [2] (referred to as “BRY” in [1] although it would be ...

In this paper we study a partially ionized plasma that corresponds to an arc discharge at atmospheric pressure. We derive an inviscid hydrodynamic/diffusion limit, characterized by two temperatures, from a system of Boltzmann type transport equations modelling that plasma problem. The original property of this system is that impact ionization is a leading order collisional process. As a consequ...

Comparison of electronand photon-impact processes as a method for determination of photo-ionization cross sections is described, discussed and shown to have many attractive features. Keywords—Transition probability, cross section, photoionization, electron-ionization, multi-photon process.

By collision-energy/electron-energy-resolved 2D Penning ionization electron spectroscopy as well as by theoretical calculations of the collisional ionization dynamics, the outer shape of molecular orbitals for ionization to X(Σ) and A(Π) states of CO was sensitively probed, and the anisotropy of the interaction between He*(2S) and CO was determined. Ionization to the B(Σ) state of CO was assign...

Electron-impact ionization cross sections for helium are calculated using time-dependent close-coupling theory. In a frozen-core approximation, the wave function for the three-electron system is expanded in terms of two-electron wave functions which fully describe the ejected and scattered electrons at all times following the collision. The resulting close-coupled partial differential equations...

The nonlocal enhancement in the velocities of charge carriers to ionization is shown to outweigh the opposing effects of dead space, increasing the avalanche speed of short avalanche photodiodes (APDs) over the predictions of a conventional local model which ignores both of these effects. The trends in the measured gain–bandwidth product of two short InAlAs APDs reported in the literature suppo...

Two-electron sum-momentum distributions from nonsequential double ionization of He in an intense laser field are analyzed. The results of a S-matrix calculation show that the inelastic scattering of the first electron with the residual ion is best considered as a ~internal! laser-induced impact ionization. The parallel component of the sum momentum is found to be largest when the prescattering ...

Laser-induced electron recollisions are fundamental to many strong field phenomena in atoms and molecules. Using the recently developed quantitative rescattering theory, we demonstrate that the nonsequential double ionization NSDI of atoms by lasers can be obtained quantitatively in terms of inelastic collisions of the target ions with the free returning electrons where the latter are explicitl...

C. William McCurdy, Daniel A. Horner, and Thomas N. Rescigno Lawrence Berkeley National Laboratory, Computing Sciences, Berkeley, California 94720 Department of Applied Science, University of California–Davis, Livermore, California 94551 Department of Chemistry, University of California, Berkeley, California 94720 Lawrence Livermore National Laboratory, Physics and Advanced Technologies, Liverm...

We consider a modiied time-dependent van Roosbroeck system with saturating velocities and a source term subject to assumptions designed to permit a standard generation term corresponding to impact ionization. This is then a nonlinear parabolic system with a right hand side of the form S = S(:; u;ru;E), coupled with the map L : u 7 ! E deened by the Poisson equation at each t. The analysis leads...