DISTINGUISHING BETWEEN SPHERICAL AND NONSPHERICAL PARTICLES BY MEASURING THE VARIABILITY IN AZIMUTHAL LIGHT-SCATTERING

Azimuthal variabilities in scattering of monochromatic, circularly pol arized light by individual spherical and nonspherical particles were m easured using the DAWN-A (Wyatt et at. Appl. Opt. 27:2405-2421, 1988) differential light scattering detector, Measured aerosols included pol ystyrene latex spheres (PSL), quartz, and sodium chloride particles of 0.576, 0.731, 0.966, and 1.250 mu m diameter. Signals from eight dete ctors at different azimuthal angles at a polar angle of 55 degrees sho wed that variabilities for nonspherical particles significantly exceed ed values for the spherical PSL. The probability that a quartz or sodi um chloride particle would be incorrectly identified as a sphere are l ess than about 5% for all sizes investigated.