propBG: A program for calculating the intensity and the far-field profile of harmonics emitted by a dilute gas irradiated by an intense Gaussian or Bessel-Gauss laser beam

Using the Green's function of the scalar wave equation, the program propBG computes and analyzes the far-field amplitude of the harmonics generated when a linearly polarized Gaussian or Bessel-Gauss beam of order zero passes through a dilute gaseous atomic target. The user must supply the relevant atomic data, namely the intensity-dependent atomic dipole moments, linear atomic susceptibilities (both at the fundamental and the harmonic frequencies), and photoionization rate. Target depletion and phase-mismatch due to photoionization are taken into account. (C) 2000 Elsevier Science B.V. All rights reserved.