Transcript No Slide Title

International Microgravity Plasma Facility
John Goree
IMPF
The University of Iowa
International Microgravity Plasma Facility
What is a dusty plasma?
-
plasma = electrons + ions
Plasma
-
small particle
of solid matter
• absorbs
electrons and
ions
+
+
+
-
+
+
-
• becomes
negatively
charged
-
+
-
+
+
D
-
• Debye
shielding
IMPF
International Microgravity Plasma Facility
+
-
Other names for Dusty Plasmas
• Complex plasmas
(analogy to complex fluids)
• Fine-particle plasmas
IMPF
International Microgravity Plasma Facility
Who cares about dusty plasmas?
Solar system
• Rings of Saturn
• Comet tails
Manufacturing
• Particle contamination
(Si wafer processing)
• Nanomaterial synthesis
Basic physics
• Coulomb crystals
• Waves
IMPF
International Microgravity Plasma Facility
Rapid Growth of this Scientific Field:
Dusty plasma publications
in APS & AIP journals
160
data
*1999 publications 9
aremonths
more
numerous than shown here.
in 1999
At the time this figure was prepared
data was available only
for Jan - Oct. 1999
80
0
IMPF
90
91 92
93
94
95
96
97
9 8 99*
International Microgravity Plasma Facility
Particles
used in Basic Physics Experiments
polymer microspheres
 8 mm diameter
separation a  0.5 mm
charge
IMPF
Q  - 104 e
International Microgravity Plasma Facility
Forces Acting on a Particle
Coulomb
Gravity
QE
mg
Other forces:
• Gas drag
• Ion drag
• Thermophoresis
• Radiation Pressure
IMPF
International Microgravity Plasma Facility
Electrostatic trapping of particles
electrode
electrode
positive
potential
QE
mg
electrode
electrode
IMPF
Equipotential
contours
Without gravity,
particles fill
3-D volume
With gravity,
particles
sediment to
high-field
region
 2-D layer
International Microgravity Plasma Facility
Need for microgravity
Gravity
 severe sedimentation
 on Earth, 2-D experiments only
Microgravity enables 3-D experiments
IMPF
International Microgravity Plasma Facility
History of IMPF
1999
• Proposal to ESA by PI Greg Morfill
result: one of six rated excellent
• International Advisory Board
formed
• DLR funds Phase A feasibility
study
2000
• Pre-Development Phase B
started
IMPF
International Microgravity Plasma Facility
International Advisory Board for IMPF
13 members
9 countries
7 meetings 5/99 - 5/01
IMPF
International Microgravity Plasma Facility
Predecessor microgravity experiments
1996-1998 Sounding rockets Morfill et al., PRL 1999
2000 - Mir
Russian
“High Energy Density
Research Center”
IMPF
International Microgravity Plasma Facility
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
IMPF
International Microgravity Plasma Facility
PKE vacuum chamber
ground
plasma
&
particles
ground
field
of
view
insulator
rf
electrode
dust dispenser
Laser
sheets for
illuminating
particles
IMPF
Cameras
for imaging
particles
International Microgravity Plasma Facility
PKE
Who:
Germany:
PI G. Morfill (MaxPlanck Institute)
Russia:
Purpose:
Study 3D dusty plasmas:
– fundamental structure
– dynamics of melting and
freezing phase transitions
High-Energy Density
Research Center,
Moscow
NASA-funded co-I:
John Goree (U. of Iowa)
IMPF
International Microgravity Plasma Facility
PKE timeline
2/26/01
Launched (Progress)
3/01 – 5/01
First experiments
(40 hours)
10/01
Next series of
experiments
IMPF
International Microgravity Plasma Facility
PKE Results
particles
void
IMPF
Crystal beginning to anneal
International Microgravity Plasma Facility
PKE - Results
Coalescence of
two suspensions
(A sequence of
video frames is
shown here, as
the plasma
power was
decreased)
IMPF
International Microgravity Plasma Facility
Scope of IMPF Science Projects
Basic
science:
Applications:
•• Melting
Particle coating
•• Self-organization
Nanoscale mfg.
•• Waves
Particle growth
• Shocks
• Defect dynamics
• Few-body systems
• much more ...
IMPF
International Microgravity Plasma Facility
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
IMPF
International Microgravity Plasma Facility
www.microgravity.net
IMPF
International Microgravity Plasma Facility