Speaker
Hubertus M. Thomas
Description
See the full Abstract at http://ocs.ciemat.es/EPS2018ABS/pdf/I5.014.pdf
Complex plasma research on the International Space Station (overview and
novel directions)
H.M. Thomas1, M. Schwabe1, M.Y. Pustylnik1, C. Knapek1, S.A. Khrapak1, V.I. Molotkov2,
A.M. Lipaev2, O.F. Petrov2 and V.E. Fortov2
1
Institut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt (DLR), 82234
Weßling, Germany
2
RAS – Joint Institute for High Temperatures, Izhorskaya 13/19, Moscow, 127412, Russia
Complex plasmas are plasmas containing solid particles typically in the micrometer range.
These microparticles are highly charged and become an additional, dominating component of
the plasma. Complex plasmas are ideal model systems to study strong coupling phenomena
in classical condensed matter. They offer the unique opportunity to go beyond the limits of
continuous media down to the fundamental length scale of classical systems - the
interparticle distance - and thus to investigate all relevant dynamic and structural processes
using the fully resolved motion of individual particles, from the onset of cooperative
phenomena to large strongly coupled systems.
Unlike “regular” plasma species the charged microparticles are strongly affected by gravity.
An electric field in the sheath or a temperature gradient are usually employed to compensate
for gravity, which provides favourable conditions to study 2D or stressed 3D systems on
ground. However, in order to perform precision measurements with large isotropic 3D
systems in the bulk plasma, microgravity conditions are absolutely necessary.
Since 2001 this research under microgravity conditions has continuously been performed on
the International Space Station ISS within the Russian/German(European)
Plasmakristall(PK)-Program. In long-term research laboratories PKE-Nefedov (2001-2005),
PK-3 Plus (2006-2013) and PK-4 (2014-ongoing), fundamental processes in liquid or
crystalline complex plasmas as well as generally in plasma physics were addressed.
Highlights are: refinement of theory of ion drag, electrorheological plasmas, lane formation
or phase separation in binary mixtures, crystallisation and melting, wave propagation, shear
flow and transition to turbulent motion.
In this presentation we will review important results from microgravity experiments and will
discuss the perspectives for future research.
Acknowledgements: The projects on the ISS were funded by DLR, BMWi, ESA, State of
Bavaria, MPG, JIHT-RAS, and ROSCOSMOS.
