the force contribution from radiation pressure. This is given as: The direction of the force vector, is that of the incident radiation of photon flux . The radius of the dust particle is . For the drag force there are two major components of interest, those from positive ions-dust particle interactions, and neutral-dust particle interactions. Ion-dust interactions are further divided into three different interactions, through regular collisions, through Debye sheath modifications, and through coulomb collisions. The thermophoretic force is the force that arises from the net temperature gradient that may be present in a plasma, and the subsequent pressure imbalance; causing more net momentum to be imparted from collisions from a specific direction. Then depending in the size of the particle, there are four categories: Very small particles, where dominates over . Small grains, where q/m ≈ , and plasma still plays a major role in the dynamics. Large grains, where the electromagnetic term is negligible, and the particles are referred to as grains. Their motion is determined by gravity and viscosity. Large solid bodies. In centimeter and meter-sized bodies, viscosity may cause significant perturbations that can change an orbit. In kilometer-sized (or more) bodies, gravity and inertia dominate the motion. Laboratory dusty plasmas Dusty plasmas are often studied in laboratory setups. The dust particles can be grown inside the plasma, or microparticles can be inserted. Usually, a low temperature plasma with a low degree of ionization is used. The microparticles then become the dominant component regarding the energy and momentum transport, and they can essentially be regarded as single-species system. This system can exist in all three classical phases, solid, liquid and gaseous, and can be used to study effects such as crystallization, wave and shock propagation, defect propagation, etc. When particles of micrometer-size are used, it is possible to observe the individual particles. Their movement is slow enough to be able to be observed with ordinary cameras, and the kinetics of the system can be studied. However, for micrometer-sized particles, gravity is a dominant force that disturbs the system. Thus, experiments are sometimes performed under microgravity conditions during parabolic flights or on board a space station. See also Padma Kant Shukla—coauthor of Introduction to Dusty Plasma Physics Heremba Bailung Notes External links Forschungsgruppe komplexe Plasmen - DLR Oberpfaffenhofen References Dusty Plasmas: Physics, Chemistry and Technological Impacts in Plasma Processing, John Wiley & Sons Ltd. Merlino, Robert L., "Experimental