AAAR 35th Annual Conference October 17 - October 21, 2016 Oregon Convention Center Portland, Oregon, USA
Abstract View
A General Description of the Angular Distribution of Light Scattered by Particles of Arbitrary Shape
CHRIS SORENSEN, Yuli Heinson, Justin Maughan, William Heinson, Amit Chakrabarti, Kansas State University
Abstract Number: 113 Working Group: Aerosols, Clouds, and Climate
Abstract We present a general description of the angular distribution of light scattered (the phase function) by particles of arbitrary shape. This description includes particles found in the atmosphere such as mineral dusts, ice crystals, soot and spherical drops. Our method analyzes the scattered light as a function of the scattering wave vector q=2ksin(theta⁄2) where k = 2pi/lambda on a log-log plot, as opposed to plotting versus linear scattering angle theta. This Q-space analysis uncovers patterns common to all particles: a q-independent forward scattering lobe is followed by a Guinier regime, a power law regime with quantifiable exponents, and sometimes an enhanced back scattering regime. We show that the internal coupling parameter ρ$^'=2kR|(m$^2-1)⁄(m$^2+2)|unifies the description. We also show that approximately half of the scattered light occurs in the forward scattering lobe for which theta ≤ lambda/D, where D is the particle size. Finally, the effects of the imaginary part of the refractive index are included in this universal description.