Binary encounter calculations on electron impact double ionization of noble gas atoms

Abstract

Electron impact double ionization cross sections of noble gas atoms have been calculated in the binary encounter approximation by using Gryzinski's double binary encounter model. The correct expression for σΔE including exchange and interference as given by Vriens has been used. Hartree–Fock and hydrogenic velocity distribution functions have been used in considering the ejection of the first and the second atomic electron, respectively. Contribution of ionization from inner-shell has also been taken into account. Calculated values of cross sections are found to be in agreement with the experimental observations.

Single and double ionization of neon 2s- and 2p-subshells by proton and electron impact

“…Gryzinski [-14] has presented a mathematical formu-lation of impact induced single and double ionization of also heavy atoms based on the classical binary encounter theory, which successfully reproduces the cross sections for single and double ionization of He by electron impact and which gives also satisfactory agreement with experimental data for K-shell double ionization of heavier elements like Mg, Cr and Fe by electron impact [15,16]. A more refined version of this classical model has been applied recently by Kumar and Roy [17,18] to double ionization of rare gas atoms by electron impact. A comparison of our data with the predictions of Gryzinski's classical model will be given.…”

Single and double ionization of gallium by electron impact

“…The method of calculating electron impact double ionization cross sections of atoms in double binary encounter model has been discussed in detail in earlier publications [21,25,28]. However, a brief account of the expressions used in the calculations seems to be desirable.…”

Pulse-periodic CF4laser with circulation of the working gas

“…The expressions for electron impact double ionisation cross sections have been derived in detail by Roy and Rai (1973) (see also Kumar and Roy 1978). The final form of this expression is as follows:…”

“…Mittleman (1966) has suggested a quantal calculation for evaluating double ionisation cross sections of atoms. Mittleman's model is not entirely correct and is expected to make significant contributions only at high impact energies (see Rai 1973, Kumar andRoy 1978). Another quantal calculation reported by Tweed (1973) has been carried out only for He, Li+ and H-.…”

“…A simplified double binary encounter model suggested by Gryzinski (1965) has been quite successful in predicting the electron and proton impact double ionisation cross section for a number of atoms and ions. The success of the method given by Roy and Rai (1973) in the case of He and Li+ and subsequent work by Kumar and Roy (1978) for other noble gas atoms has been quite encouraging and it is desirable to apply this method in the case of other complex atoms, e.g. alkaline earths.…”