On the Integral Characteristics of Single Scattering on Nonspherical Particles

Expressions are obtained for the integral characteristics of single scattering of polarized radiation on particles of arbitrary shape. Polarized radiation is described by Stokes parameters. The two known scattering characteristics are examined—the full scattering cross section and the scattering matrix normalization constant. A dimensionless scattering integral is analyzed that takes into account possible scattering of incident radiation in all directions and determines the two considered integral characteristics. The integral is expressed via the scattering matrix elements and Stokes parameters of incident radiation. In the case of a nonspherical particle, the matrix elements depend on the direction of radiation incident on the particle. In this connection, the total scattering is affected by the structure of the incident beam. The practically important cases of particle illumination by parallel and convergent beams are considered. Expressions are obtained for the integral characteristics, averaged over the directions of incident radiation. Simple relations between the two scattering characteristics under different particle illumination are derived.