ELSEPA - Dirac Partial-Wave Calculation of Elastic Scattering of Electrons and Positrons by Atoms, Positive Ions and Molecules
Francesc Salvat, Aleksander Jablonski, Cedric J. Powell
The FORTRAN 77 code system ELSEPA for the calculation of elastic scattering of electrons and positrons by atoms, postive ions and molecules is presented. These codes perform relativistic (Dirac) partial wave calculations for scattering by a local central interaction potential V (r). For atoms and ions, the static-field approximation is adopted, with the potential set equal to the electrostatic interaction energy between the projectile and the target, plus an approximate local exchange interaction when the projectile is an electron. For projectiles with low and intermediate kinetic energies (up to 250 KeV), the potential may optionally include an imaginary absorptive part (to account for the depletion of the projectile wave function caused by open inelastic channels) and a semiempirical correlation-polarization potential (to describe the effect of the target charge polarizability). Molecular cross sections are calculated by means of a single-scattering independent-atom approximation, in which the electron density of a bound atom is approximated by that of the free neutral atom. Elastic scattering by individual atoms in solids is described by means of a muffin-tin model potential. Partial-wave calculations are feasible on modest personal computers for energies up to about 5 MeV.
, Jablonski, A.
and Powell, C.
ELSEPA - Dirac Partial-Wave Calculation of Elastic Scattering of Electrons and Positrons by Atoms, Positive Ions and Molecules, Computer Physics Communications
(Accessed December 10, 2023)