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Abstract Complex plasma is a state of soft matter where micrometer-sized particles are immersed in a weakly ionized gas. The particles acquire negative charges of the order of several thousand elementary charges in the plasma, and they can form gaseous, liquid and crystalline states. Direct optical observation of individual particles allows to study their dynamics on the kinetic level even in large many-particle systems. Gravity is the dominant force in ground-based experiments, restricting the research to vertically compressed, inhomogeneous clouds, or two-dimensional systems, and masking dynamical processes mediated by weaker forces. An environment with reduced gravity, such as provided on the International Space Station (ISS), is therefore essential to overcome this limitations. We will present the research goals for the next generation complex plasma facility COMPACT to be operated onboard the ISS. COMPACT is envisaged as an international multi-purpose and multi-user facility that gives access to the full three-dimensional kinetic properties of the particles.
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“Zyflex”: Next generation plasma chamber for complex plasma research in space
In this paper, we give a detailed description of a novel plasma chamber—the Zyflex chamber—that has been specifically designed for complex/dusty plasma research under reduced gravitational influence as realized during parabolic flight or aboard the International Space Station. The cylindrical, radio-frequency driven discharge device includes a variety of innovations that, for example, allow us to flexibly adjust plasma parameters and its volume via enhanced plasma generation control and a movable, multi-segmented electrode system. The new complex/dusty plasma research tool also supports, due to its overall increased size compared to former space based complex plasma experiments such as PKE-Nefedov or PK-3 Plus, much larger particle systems. Additionally, it can be operated at much lower neutral gas pressures, thus reducing the damping of particle motion considerably. Beyond the technical description and particle-in-cell simulation based characterization of the plasma vessel, we show sample results from experiments performed with this device in the laboratory as well as during parabolic flights, both of which clearly demonstrate the new quality of complex/dusty plasma research that becomes accessible with this new plasma device.
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- Award ID(s):
- 1655280
- PAR ID:
- 10592736
- Publisher / Repository:
- American Institute of Physics
- Date Published:
- Journal Name:
- Review of Scientific Instruments
- Volume:
- 92
- Issue:
- 10
- ISSN:
- 0034-6748
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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