Application of the binary-encounter theory to proton impact double ionisation of atoms

Anomalous Leakage Current of MOSFET's under BT Stress

“…The various terms used in the above expressions have been explained by Roy and Rai (1973) (see also Kumar and Roy 1978). The total electron impact direct double ionisation cross section (including the inner-shell contributions) can be written as Q"(T) = Qb( as, ns) + Qb( ns, ( n -1)p) + Qb( as, (PI -1)s)…”

“…Here Qb( as, ( n -1)p) stands for the direct double ionisation cross section in which one electron is ejected from the ns shell (valence shell) and other from the ( nl ) p shell. The factor ne( ne-1)/4.irT2 has been suitable modified while considering the last two modes of ionisation (see Kumar and Roy 1978).…”

“…For uAE we have used Vriens ' (1966) In the present work we have used the values of binding energy for different shells of the target and their ions as given by Lotz (1968) and the quantum mechanical values of radial distances of maximum electron density given by Desclaux (1977) as shell radii. To construct the momentum distribution function f ( t ) (see Kumar and Roy 1977) we have made use of the Hartree-Fock radial wavefunctions as given by Clementi and Roetti (1974).…”

“…Investigations of electron impact single and multiple (particularly double) ionisation of atoms and ions are of considerable importance due to their applications in various fields (see Roy and Rai 1973, Kumar and Roy 1978, Moores et a1 1980, Muller and Frodl 1980, Jakubowicz and Moores 1981, Crandall 1981, Younger 1981, Rogers et a1 1982, Chatterjee et a1 1982, Achenbach et al 1983. Experimentally the process of multiple ionisation (mainly double) of atoms and ions due to impact of electrons has been extensively studied in low-, intermediate-and high-energy regions (see Bleakney 1930, Tate and Smith 1934, Harrison 1956, Stanton and Monahan 1960, Stuber 1965, Fiquet-Fayard 1965, Rapp and Englander Golden 1965, Schram et a1 1964, Schram 1966, Ziesel 1967, Ziesel and Abouaf 1967, McFarland 1968, Peart and Dolder 1969, van der Wiel et a1 1969, Okuno et a1 1970, Okudaira 1970, Okuno 1971, Karstensen and Schneider 1978, Muller and Frodl 1980, Hughes and Feeney 1981, Dettmann and Karstensen 1982, Muller et a1 1983, Achenbach et a1 1983.…”

“…Roy and Rai (1973) developed a modified binary encounter model for calculations of electron impact double ionisation of atoms and ions and successfully applied it for He and Li+ targets. Later on the same method was applied for the investigation of the process X+e+X2'+3e ( X = N e , A r , K r , X e ) by Kumar and Roy (1978) and for M g + e -+ Mg2++3e by Chatterjee et a1 (1982). Encouraging results in these cases inspired us to use the above model, with required modifications for the computation of electron impact double ionisation cross sections for Ca and Sr.…”