Spin-oprbit Coupling Effects In Parameters That Describe Electron-photon Coincidence Experiments

Parameters are introduced to characterize the electron-photon coincidence rate for atoms where spin-orbit interaction is present in the radiating target state. It is shown that two of these parameters (called and) obey rigorous selection rules which require that they go to 2 at 0°and 180°electron scattering angles in the presence of spin-orbit coupling while their limit in the LS-coupled case is 0. Numerical results are presented. © 1980 The American Physical Society.45141164116

Electron-impact Excitation Of The Lowest Four Excited States Of Argon

First-order many-body theory has been used to calculate the differential and integral cross sections for electron-impact excitation of the argon atom to the 4 P03, 4 P23, 4 P13, and 4 P11 electronic states, for incident electron energies of 16, 20, 30, 50, and 80.4 eV. The resulting cross sections are in good agreement with recent results extracted from electron energy-loss measurements on argon. Detailed calculations show that spin-orbit coupling must be included in the P13 wave function in order to describe the electron-impact excitation of the state properly. © 1981 The American Physical Society.2352194221

Field-theoretical Approach To Vibrational Excitation In Atom-diatom Collinear Collisions

The field-theoretical atom-diatom scattering equations of Csanak have been tested numerically, assuming a collinear collision model, with an exponential repulsive interaction potential and with a harmonic oscillator approximation for the molecule. Dyson's equation, in its integral form, has been solved obtaining orbitals representing the elastic scattering of an atom off the target and these Dyson's orbitals have been used to evaluate a matrix element containing a transition potential. This has been obtained by approximating Bethe-Salpeter's equation and yields directly the transition amplitudes for inelastic scattering. The results for single and multiple-jumps compare favourably with the exact values of Secrest and Johnson, and refinements of the model are suggested for further improvements. © 1976.143353363Csanak, Taylor, Ficocelli Varracchio, (1974) J. Chem. Phys., 61, p. 263Roman, (1969) Introduction to Quantum Field Theory, , Wiley, New YorkSecrest, Johnson, Exact Quantum-Mechanical Calculation of a Collinear Collision of a Particle with a Harmonic Oscillator (1969) The Journal of Chemical Physics, 45, p. 4556Ficocelli Varracchio, Atom-diatom inelastic scattering: a comparison of the many-body and distorted wave theories (1975) Molecular Physics, 30, p. 1117Ficocelli Varracchio, (1975) Abstracts of papers IX Intern. Conf. Physics of Electronic and Atomic Collisions, p. 553. , University of Washington Press, SeattleAbramowitz, Stegun, (1972) Handbook of Mathematical Functions, p. 374. , Dover, New YorkMarriott, (1958) Proc. Phys. Soc. (London), 72, p. 121Thomas, (1973) J. Comput. Phys., 13, p. 348Thiele, Weare, (1968) J. Chem. Phys., 48, p. 2324Koppel, Lin, (1973) J. Chem. Phys., 58, p. 1869Jackson, Mott, Energy Exchange between Inert Gas Atoms and a Solid Surface (1932) Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences, 137 A, p. 703Rapp, Kassal, Exact Quantum-Mechanical Calculation of Vibrational Energy Transfer to an Oscillator by Collision with a Particle (1968) The Journal of Chemical Physics, 48, p. 5287Morse, Feshbach, (1953) Methods of Theoretical Physics, , McGraw—Hill, New Yor