Positron-atom scattering using a modified Kohn variational technique
- 11 January 1976
- journal article
- Published by IOP Publishing in Journal of Physics B: Atomic and Molecular Physics
- Vol. 9 (1) , 67-74
- https://doi.org/10.1088/0022-3700/9/1/008
Abstract
An analysis of the zero-energy positron-hydrogen and positron-helium systems using various approximations to the target ground-state wavefunction is presented. A modification of the normal Kohn variational method is used in which a quantity, aQ, which becomes the Kohn scattering length if the target wavefunction is exact, is related to the trial wavefunction Psi t through an integral expression. By comparing the results obtained with the definitive values for the positron-hydrogen system, it is conjectured that if the values of aQ display a local minimum when all the nonlinear parameters of Psi t are varied, then this local minimum of aQ is an upper bound on the exact scattering length. Using this criterion to analyse the positron-helium results, it is concluded that this method may be considered as an alternative to the 'method of models' procedure, since both methods give similar results.Keywords
This publication has 14 references indexed in Scilit:
- Calculation of electron or positron-atom scattering lengths using approximate target wavefunctionsJournal of Physics B: Atomic and Molecular Physics, 1975
- Electron and positron scattering by helium and neonJournal of Physics B: Atomic and Molecular Physics, 1975
- Evaluation of some integrals required in low-energy electron or positron-atom scatteringJournal of Computational Physics, 1975
- Positron-helium scattering lengthJournal of Physics B: Atomic and Molecular Physics, 1974
- Annihilation in positron-helium scatteringJournal of Physics B: Atomic and Molecular Physics, 1974
- Total cross sections for the scattering of positrons by heliumJournal of Physics B: Atomic and Molecular Physics, 1974
- The scattering of low energy positrons by heliumJournal of Physics B: Atomic and Molecular Physics, 1973
- The method of models in variational scattering calculationsJournal of Physics B: Atomic and Molecular Physics, 1972
- Positron-Atom Scattering by the Kohn and Harris MethodsPhysical Review A, 1971
- Atomic Integrals Containing r23λ r31μ r12vThe Journal of Chemical Physics, 1968