Measured Light-Scattering Properties of Individual Aerosol Particles Compared to Mie Scattering Theory

Abstract
Monodispersed spherical aerosols of 0.26–2-μ diameter with approximate range of indexes of refraction of atmospheric aerosols have been produced in the laboratory by atomization of liquids with a vibrating capillary. Integrated light scattered 8 through 38 degrees from the direction of forward scattering has been measured with a photoelectric particle counter and compared to Mie theory calculations for particles with complex indexes of refraction 1.4033–0i, 1.592–0i, 1.67–0.26i, and 1.65–0.069i. The agreement is good. The calculations take into account the particle counter white light illumination with color temperature 3300 K, the optical system geometry, and the phototube spectral sensitivity. It is shown that for aerosol particles of unknown index of refraction the particle counter size resolution is poor for particle size greater than 0.5μ, but good for particles in the 0.26–0.5-μ size range.