LIGHT SCATTERING BY MULTI-LAYERED PARTICLES
                       WITH THE AXIAL SYMMETRY

                          V.G. Farafonov
    St.Petersburg State University of aerocosmic instrumentation,
                      St.Petersburg, Russia


                             Abstract

A new recursive algorithm of solution of the problem of
scattering of an arbitrary polarized plane wave by multi-layered
dielectric particles with the axial symmetry is constructed.
The approach used is that suggested and realized earlier for
homogeneous axisymmetric particles. Its main features are:
1) presentation of the fields as sums of two components where
the first one does not depend on the azimuthal angle and averaging
the second one gives zero;
2) solution of the axisymmetric problem using the scalar potentials
connected with the azimuthal components of electromagnetic fields;
3) solution of the nonaxisymmetric problem with the usage of a
superposition of Debay? potentials and vertical components of
magnetic or electric Hertz vector.
Important for the considered solution is the formulation of the
light scattering problem as surface integral equations for the
scalar potentials which are represented by expansions in term of
spherical wave functions. Simple structure infinite systems of
algebraic linear equations are obtained for unknown expansion
coefficients. The size of truncated? systems for multi-layered
particles coincides with that of analogical homogeneous particles.
In the case of multi-layered spherical particles the considered
algorithm provides solution in explicit way, where the dependence
on the radial spherical functions for layers is given by logarithmic
derivative (i.e. the ratio of a derivative to the function).