PK-4: Self-Ordering of Interacting Complex Plasma Particles in Microgravity

Baylor University, Waco TX

Investigators

Abstract

This project will utilize a facility called Plasma Krystal-4 (PK-4) on the International Space Station to conduct experiments in microgravity investigating the underlying physics behind self-ordering of interacting complex plasma dust particles. Complex plasma, also known as dusty plasma, consist of ions, electrons and charged nanometer to micron sized solid particles known as dust. Dusty plasmas have long been of interest in the astrophysics community. For example, the material from which stars and planets form, interstellar clouds, and even planetary rings all consist of dusty plasma. Dusty plasmas are also present on the Earth, particularly in industrial plasma applications, while the controlled formation of dust crystals in a laboratory setting provides a useful analog for both atomic and molecular systems, allowing fundamental progress in our understanding of the physics involved. As such, dusty plasma research enables the progress of science while allowing insight into practical issues of yield efficiency in semiconductor manufacturing. This award will also impact the STEM workforce through engagement of students who will develop computation and modeling skills, obtain practical experience with instrumentation, and improve their technical writing and presentation skills. A proper understanding of the physics underlying the field of dusty plasma research is complicated by the fact that the majority of research conducted occurs in a gravitational environment (i.e., on the Earth). This project directly addresses this issue, utilizing a multinational collaboration to compare studies on self-ordering of interacting complex plasma dust particles collected on the Earth to experimental results employing the PK-4 facility under microgravity. Data obtained will be compared with data from two different ground-based experiments as well as to results provided by numerical modeling of the plasma / dust environment using a comprehensive set of analysis techniques. This combination will be used to define the parameter space where particular wave modes can exist, and to develop comprehensive theories on interparticle potential and grain-plasma interactions, determining the microscopic and macroscopic properties of the complex plasma. The results obtained will directly impact research in astrophysics and planetary science (e.g., dust in protoplanetary disks, charged dust on the surface of airless bodies, such as the moon and asteroids, planetary ring systems), atmospheric physics (e.g., noctilucent clouds), fusion research (e.g., dust contamination), materials physics (e.g., soft matter, metastable states, complex fluids, granular matter), and advanced manufacturing (e.g., semiconductor, etching, and deposition systems). This award is made under a "NASA/NSF Partnership on Science of Dusty Plasmas: Utilizing the PK-4 Facility on board the International Space Station"; a complementary NASA award to support an undergraduate student is being made under the joint program.