A Study of Homogeneous Condensation-Freezing Nucleation of Small Water Droplets in an Expansion Cloud Chamber

Abstract

Observations of the homogeneous nucleation of water vapor in an expansion cloud chamber have been carried out for the temperature range -50 to +17*C in the carries gases argon and helium. We have found that the onset of the ice phase in freshly nucleated drops alwyas occurs in the form of a tw0-stage process, condensation followed by homogeneous freezing at temperatures near -40*C. Ice particles appear as brilliant spherical particles in the cloud of liquid drops wit=ch scatter much less light...