Stokes vector for small rough particles: Regression analysis

The Stokes parameters and the linear polarization Pl of small rough particles composed of ice and silicate are studied with statistical methods. The probability density function of Pl and a regression analysis for the first two Stokes parameter Is2 and Qs2 are presented for three typical scattering angles θs=60°, 90° and 150°. The width of the probability density function of Pl given by its standard deviation increases with the roughness of the particles. A linear relationship between Is2 and Qs2 is found by the regression analysis. The slope of the linear model reflects the correlation between Is2 and Qs2 that, for a specific composition of the particles, depends on the roughness of the particles and the scattering angles. The value of the constant of the linear regression is characteristic of the composition of the particles and is not sensitive to the roughness of the particles and the scattering angles. The scattering angle θs=150° is the most appropriate angle for a study of rough particles of different composition.