Abstract
A single-layer suspension of microparticles was formed in a plasma under microgravity conditions. This single layer is confined at a void boundary by a balance of ion drag and electric forces, where the ion flow velocity is much slower than in the sheath of laboratory plasmas. Using a high-resolution camera that allows measurements of velocities at a low level, the microparticle kinetic temperature was found to be close to that of the neutral gas. The random motion transverse to the single layer was found to have oscillations of the form expected for harmonic oscillators driven by white noise. The driving of the oscillation is mostly attributed to the Brownian motion of neutral atoms, while the damping is mostly due to neutral gas friction. An observed resonance frequency of 25 s−1 allows us to quantify the electric and ion drag forces as being in the range of 0.2–0.4mpg, where mp is the microparticle mass and g is the acceleration of gravity on Earth’s surface. No signature of wave dispersion was detected for this experiment with neon at a pressure of 0.12 Torr.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
