Hypervelocity dust storm launched with a coaxial plasma gun

A dust storm consisting of carbon grains accelerated to speeds up to ∼3 km/s has been launched by a plasma jet produced in a coaxial gun. Diamond and graphite powders with grain radii of 0.5 to 30 microns have been used. A distinctive feature of this plasma accelerator is that it can use different types of gases and can operate with microparticles having any shape and a large range of sizes. Deuterium gas and carbon dust is chosen to be compatible with fusion plasmas as a diagnostic tool. The operating voltages of the coaxial gun are between 5 and 10 kV and the maximum measured discharge current is ∼250 kA. Imaging of the plasma jet exiting the gun with speeds of 25 to 60 km/s and accelerated by the J × B force shows a good collimation of the flow for about 1.5 m, before it diffuses into a large a vacuum tank.