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International Microgravity Plasma FacilityIMPFIMPF
International Microgravity Plasma Facility
John Goree The University of Iowa
International Microgravity Plasma FacilityIMPFIMPF
plasma = electrons + ions Plasma
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What is a dusty plasma?
D
• Debye shielding
small particle of solid matter
• becomes negatively charged
• absorbs electrons and ions
International Microgravity Plasma FacilityIMPFIMPF
Other names for Dusty Plasmas
• Complex plasmas (analogy to complex fluids)
• Fine-particle plasmas
International Microgravity Plasma FacilityIMPFIMPF
Solar system• Rings of Saturn• Comet tails
Basic physics• Coulomb crystals• Waves
Manufacturing• Particle contamination
(Si wafer processing)
• Nanomaterial synthesis
Who cares about dusty plasmas?
International Microgravity Plasma FacilityIMPFIMPF9 0 9 1 9 2 9 3 9 4 9 5 9 6 9 7 9 8 9 9 *
*1999 publications are morenumerous than shown here.At the time this figure was prepareddata was available onlyfor Jan - Oct. 1999
0
80
160 9 months data in 1999
Rapid Growth of this Scientific Field:Dusty plasma publications
in APS & AIP journals
International Microgravity Plasma FacilityIMPFIMPF
polymer microspheres
8 m diameter
Particles used in Basic Physics Experiments
separation a 0.5 mm
charge Q - 104 e
International Microgravity Plasma FacilityIMPFIMPF
Forces Acting on a Particle
Coulomb
QE
Other forces:• Gas drag• Ion drag• Thermophoresis• Radiation Pressure
Gravity
mg
International Microgravity Plasma FacilityIMPFIMPF
Electrostatic trapping of particles
Equipotentialcontours
electrode
electrode
positive
potential
electrode
electrode
With gravity, particles sediment to high-field region 2-D layer
Without gravity, particles fill 3-D volume
QE
mg
International Microgravity Plasma FacilityIMPFIMPF
Gravity severe sedimentation
on Earth, 2-D experiments only
Microgravity enables 3-D experiments
Need for microgravity
International Microgravity Plasma FacilityIMPFIMPF
• International Advisory Board formed
2000
• Pre-Development Phase B started
• DLR funds Phase A feasibility study
History of IMPF
1999
• Proposal to ESA by PI Greg Morfill
result: one of six rated excellent
International Microgravity Plasma FacilityIMPFIMPF
13 members 13 members
9 countries9 countries
7 meetings 5/99 - 5/017 meetings 5/99 - 5/01
International Advisory Board for IMPF
International Microgravity Plasma FacilityIMPFIMPF
Predecessor microgravity experiments
2000 - Mir Russian “High Energy Density Research Center”
1996-1998 Sounding rockets Morfill et al., PRL 1999
International Microgravity Plasma FacilityIMPFIMPF
Predecessor microgravity experiments
PKE - Plasma Kristall Experiment
1999 - Parabolic flight tests
2000-01 - ISS• Feb. 2001 - launch• 2001 - the 1st physical sciences
experiment on ISS
PKE flight hardware with 1st & 3rd ISS crews
International Microgravity Plasma FacilityIMPFIMPF
PKE vacuum chamber
insulator
ground
plasm a&
particles
ground
ground
rf electrode
fieldof
view
dust dispenser
Cameras for imaging
particles
Laser sheets for illuminating particles
International Microgravity Plasma FacilityIMPFIMPF
PKE
Purpose:
Study 3D dusty plasmas:
– fundamental structure
– dynamics of melting and freezing phase transitions
Who:
Germany:
PI G. Morfill (Max-Planck Institute)
Russia:
High-Energy Density Research Center, Moscow
NASA-funded co-I: John Goree (U. of Iowa)
International Microgravity Plasma FacilityIMPFIMPF
PKE timeline
2/26/01 Launched (Progress)
3/01 – 5/01 First experiments (40 hours)
10/01 Next series of experiments
International Microgravity Plasma FacilityIMPFIMPF
PKE Results
particles
Crystal beginning to anneal
void
International Microgravity Plasma FacilityIMPFIMPF
PKE - Results
Coalescence of two suspensions
(A sequence of video frames is shown here, as the plasma power was decreased)
International Microgravity Plasma FacilityIMPFIMPF
Scope of IMPF Science Projects
Basic science:
• Melting
• Self-organization
• Waves
• Shocks
• Defect dynamics
• Few-body systems
• much more ...
Applications:
• Particle coating
• Nanoscale mfg.
• Particle growth
International Microgravity Plasma FacilityIMPFIMPF
International AO
• Released Oct. 2000 by NASA, ESA, NASDA, CSA
• For Physical Sciences PI’s to use ISS instruments belonging to other countries
• 117 proposals were received (U.S. + Europe + Japan + Canada)
• The top 3 proposals (according to scientific merit in the peer review process) were from IMPF users
International Microgravity Plasma FacilityIMPFIMPF
www.microgravity.netwww.microgravity.net