Electromagnetic scattering by arbitrarily oriented ice cylinders.

The scattering of electromagnetic waves by arbitrarily oriented, infinitely long circular cylinders is solved by following the procedures outlined by van de Hulst. The far-field intensities for two cases of a linearly polarized incident wave are derived. The scattering coefficients involve the Bessel functions of the first kind, the Hankel functions of the second kind, and their first derivatives. Calculations are made for ice cylinders at three wavelengths: 0.7 micro, 3 micro, and 10 micro. The numerical results of intensity coefficients are presented as functions of the observation angle ø. A significant cross-polarized component for the scattered field, which vanishes only at normal incidence, is obtained. It is also shown that the numerous interference maxima and minima of the intensity coefficients due to single-particle effects depend on the size parameter x as well as on the oblique incident angle alpha. Since cylinder-type particles are often observed in ice clouds, the light-scattering calculations performed for a cir ular cylinder in this paper should be of use in the study of cloud microstructure.