Analytical Cross Section Approximation for Electron Impact Ionization of Alkali and Other Metals, Inert Gases and Hydrogen Atoms

Rusudan I Golyatina,Sergey A Maiorov

doi:10.3390/atoms9040090

Abstract

The paper presents an analysis of data on the cross sections of electron impact ionization of atoms of alkali metals, hydrogen, noble gases, some transition metals and Al, Fe, Ni, W, Au, Hg, U. For the selected sets of experimental and theoretical data, an optimal analytical formula is found and approximation coefficients are calculated. The obtained semi-empirical formula reproduces the values of the ionization cross sections in a wide range of energies with an accuracy of the order of error of the available theoretical and experimental data.

Highlights

IntroductionThe values of electron-atomic collision cross sections are used in various applications of gas-discharge plasma
Prokhorov General Physics Institute of the Russian Academy of Sciences, 38, Vavilov Str., Joint Institute for High Temperatures of the Russian Academy of Sciences, 13, Izhorskaya Str., Bd. 2, 125412 Moscow, Russia
We started a critical analysis and evaluation of the cross sections for electron scattering by noble gas atoms in a wide energy range in [7,8,9,10], where we found approximations for the cross sections of elastic and inelastic collisions of electrons with rare gas atoms

Summary

Introduction

The values of electron-atomic collision cross sections are used in various applications of gas-discharge plasma. From a large number of experimental and calculated data on ionization cross-sections, by comparative analysis, we selected the data for approximation by our analytical dependence. Ionization by electron impact from the ground state of the atom is, perhaps, the most frequent method for the formation and maintenance of a gas-discharge plasma. With a large excess of the electron energy above the ionization threshold, both experimental methods and theory provide good accuracy in measuring cross sections. As before, when choosing data for approximating ionization cross sections, we limited ourselves to considering ionization from the ground state, which is sufficient for modeling applied problems of gas-discharge plasma

Approximation of the Ionization Cross Section

Results

Discussion