OBSERVATION OF MULTI-SHELL STRUCTURE OF DUSTY CLOUD BY THE TAPD METHOD IN PLASMAS UNDER MICROGRAVITY CONDITION

摘要

We have observed a fine-particle (dust) cloud with multi-shell structure in the microgravity experiment which has been carried out by a parabolic flight of aircraft. The particle positions are controlled by the time-averaged particle driving (TAPD) method. After reaching the microgravity dust particles of 10 micron meters are injected between the RF electrodes. We have observed for the first time a generation of dust clouds between the radio frequency (RF) discharge electrodes without forming a void inside. From a careful observation the dust cloud contains a multi-shell structure like an onion. Therefore, the TAPD method is quite useful for the control of dusty cloud in the plasma center under microgravity condition.