ATTENUATION CONSTANT OF A COHERENT FIELD IN A DENSE DISTRIBUTION OF PARTICLES

In a dense distribution of particles, the propagation characteristics of the coherent field are strongly affected by the pair-correlated distributions of scatterers. This paper presents an optical experimental study to show that, when the particle density is greater than about 0. 1%, the attenuation constant departs markedly from the formula based on an uncorrelated scatter assumption. It decreases sharply when ka less than 1, whereas it shows a slight increase when ka VM GT TH 1. Experimental data are shown for the volume densities ranging from 10** minus **3 to 40% and ka ranging from 0. 529 to 82. 793. Comparisons are given with some theoretical calculations.