Experimental measurements of velocity dissipation and neutral-drag effects during the formation of a dusty plasma.

Stereoscopic particle image velocimety is used to make measurements of the formation of a dust cloud of 1.2 microm alumina particles in an argon dc glow discharge plasma. These measurements show a clear redistribution of particle velocities during the cloud formation process. Furthermore, these measurements suggest that the particle cloud reaches an equilibrium on a time scale over 100 times slower than expected due to neutral-drag effects.