Discussion of two quadrature methods of evaluating beam-shape coefficients in generalized Lorenz–Mie theory

A comparison between two quadrature methods of evaluating beam-shape coefficients in generalized Lorenz-Mie theory, in the case of incident Gaussian beams, is carried out. It is shown that, when the electromagnetic description of the Gaussian beams does not perfectly satisfy Maxwell's equations, both quadrature methods are basically flawed. These flaws do not prevent an accurate evaluation of beam-shape coefficients when their nature is correctly identified, because they produce artifacts that can easily be identified and removed.