On the Particle-Size Distribution Function of Cometary Dust

The Finson-Probstein (1968a) method of analysis of the distribution of light intensity in dust tails has so far been applied to only a handful of comets. Yet, the results already suggest a striking diversity in the properties of the particle-size related distribution function f(β), one of three parametric functions determined. Here β is the acceleration exerted on the particle by solar radiation pressure, measured in units of solar attraction. For a spherical particle β is a function of its radius a, density ρ, and the integrated efficiency factor for radiation pressure Qpr (i.e., the ratio of the particle's effective cross-section for radiation pressure to its geometric cross-section): where c0 = 0.585 × 10−4 g/cm2.