Page 223 - International Space Station Benefits for Humanity, 3rd edition.

or the potential at the central electrode—the shape
and structure of the cluster turned out to be different.
Space Experiment CC In several series of recent experiments, the cluster
was destroyed by feeding a sufficiently large potential
demonstrated, for the first time, to the central electrode to overcome the magnetic
that it is possible to form stable, confinement forces of the particles and the auto-
adhesive bonding forces between the particles upon
spatially ordered structures of their contact. Contact between particles could occur if
several thousand charged particles the magnetic field was switched on before the potential
at the central electrode. In this case, assumptions were
in a magnetic trap in microgravity made about the structure of the central electrode based
to visually observe the processes on data regarding the nature of the cluster destruction,
occurring in them and to study, with a gradual increase in the potential of the central
electrode. According to these data, the cluster can
on their example, the properties consist mainly of filamentary chains located from the
of Coulomb systems. central electrode to the periphery and occupying about
10% of its volume, and its charge will be concentrated
on the outer shell.
Space Experiment CC demonstrated, for the first
time, that it is possible to form stable, spatially ordered
structures of several thousand charged particles in a
Unlike numerous experiments with dusty plasma, magnetic trap in microgravity to visually observe the
where negatively charged particles are held in processes occurring in them and to study, on their
electrostatic traps, charged diamagnetic particles example, the properties of Coulomb systems.
are retained in the CC by magnetic forces in a cusp Students and postgraduates of the Joint Institute
magnetic trap. The main idea of the experiment is that for High Temperatures of the Russian Academy of
the forces of interaction between particles and the Sciences (JIHT RAS) and Moscow Institute of Physics
forces holding them in a trap must be of a different and Technology (MIPT) were involved in all stages of
nature so that the change in some does not affect preparation and implementation of the experiment,
the others. The cusp magnetic trap is created by two as well as analysis of the data. The results obtained
coaxial electromagnets with oppositely circulating during Space Experiment CC formed the basis of
currents in their coils. With equal currents in the coils, two Ph.D. theses.
a “magnetic well” for diamagnetic particles appears
between them. Graphite particles with the highest
diamagnetic susceptibility from all known materials
are used in the experiment. The charging of particles
was carried out through the particle contact with a
central wire electrode located along the symmetry
axis of the system. In this case, the charge of particles
could be of any sign, unlike the case of dusty plasma,
where it is always negative. Unlike plasma-dusty
structures, the proposed method makes it possible
to form stable spatial structures of charged particles
in electric discharges, both in a non-ionized gas of
various densities and in a vacuum. When the current
was changed in one of the coils, a dynamic effect
was exerted on the cluster formed by the particles.
According to the response of the cluster to this
influence, some properties were determined, both Cosmonaut Gennady Ivanovich Padalka
in the cluster itself and in the cusp magnetic trap. performs the Space Experiment CC.
Depending on what was included earlier—the current Image credit: ROSCOSMOS
in the coils of the electromagnet (i.e., magnetic field)

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