Diffusion of particles having an equal fall velocity which are released from a cross-wind line source in diabatic atmospheres is studied. The wind profile and eddy diffusivity assumed in this investigation are those proposed by Yamamoto and Shimanuki as a revision of the KEYPS formula. The solution of the resulting diffusion equation is obtained numerically for various combinations of the source height, thermal stability and terminal velocity of the articles. In addition the deposition rate of particles on the ground is estimated as a function of the downwind distance, source height and stability.
Diffusion of particles having different sizes is then estimated.