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UCLA Receives $4.8 Million Grant
to Support Research
in World's Best Plasma Physics Facility
In experiments that last a hundred-millionth of a second or just
slightly longer, UCLA physicists are learning the secrets of plasma - the
turbulent, hot, ionized, gas-like matter that may help us destroy toxic
waste and chemical and biological weapons, and perhaps help generate
unlimited energy through fusion.
UCLA's Basic Plasma Science Facility has been awarded a $4.8 million
grant by the U.S. Department of Energy and the National Science
Foundation to become the country's first national research facility for
scientists worldwide to study the mysterious properties of plasma.
Plasma is believed to make up more than 99 percent of the visible
universe, including the sun, the stars, galaxies and the vast majority
of the solar system. Plasma is a fourth state of matter, distinct from
solids, liquids and gases, in which electrons have been stripped away to
leave positively charged atoms or molecules.
"This is the best facility in the world for physicists to conduct
controlled experiments to understand the properties of plasma - research
that could have significant applications for this country," said Tony
Chan, dean of physical sciences in UCLA's College of Letters & Science.
"UCLA will be host to international physicists working at the forefront
of plasma physics."
The centerpiece of the facility is an enormous machine called the Large
Plasma Device (LAPD), which weighs more than 80 tons.
Physicist Walter Gekelman directs a UCLA project that explores the frontiers of plasma physics.
Walter Gekelman, UCLA professor of physics and director of the facility,
and five of his colleagues, built the machine - from the sophisticated
electronics and the plasma source to the plumbing and welding - over
three-and-a-half years. The machine is unique in the world, and allows
physicists to create and analyze plasma and plasma waves of superheated,
energized gas.
"Studying plasma waves in space is like finding one tooth of a dinosaur
and trying to determine what the whole dinosaur looked like," Gekelman
said. "In our machine, we can see the whole dinosaur.
"Much about plasmas and how they behave is very poorly understood," he
said. "Our machine will help us understand plasmas. We can make
measurements in tens of thousands of locations, using technology we have
developed over 30 years."
Experiments using LAPD last as little as a hundred-millionth of a
second, and always much less than a one-thousandth of a second, Gekelman
said. Plasmas in space support thousands of waves that may be 100,000
miles long, exist nowhere else in nature and dictate how the plasma
behaves.
"We can study these waves in tremendous detail, and are able to scale
them so they fit in our device," Gekelman said.
Gekelman and his research team will use the facility half the time for
research, and other physicists worldwide will propose experiments to use
the LAPD for the other half. The Westwood facility operates 24 hours a
day.
Plasmas could have many practical uses, including plasma torches that
cut through steel like butter (which Gekelman used in making LAPD),
weigh no more than a pencil and may eventually be used to destroy toxic
waste; devices that instantly destroy chemical and biological weapons
such as anthrax; improved computer chips; devices into which garbage can
be thrown and recycled; and perhaps for generating a clean and unlimited
supply of energy in the future through fusion - the energy source of the
sun.
"We are doing pure research on fundamental issues such as understanding
how heat and energy are transported through a plasma, and learning the
structure of plasmas, but the payoff could be tremendous," Gekelman
said. "Understanding these fundamental issues could help enormously with
designing and building better devices, including, perhaps, a better
fusion reactor. Until we understand the fundamental science of plasma
physics, it is like trying to cure a brain disease without knowing what
part of the brain is involved. Transport, for example, is one of the
factors preventing fusion from being a reality. If scientists understood
transport, we could design more efficient fusion devices."
Hydrogen bombs are plasma, and after the first hydrogen bomb was
exploded, scientists realized an unlimited supply of energy could be
tapped if we can control fusion, Gekelman noted. Efforts to do so in the
1950s failed, he said, because attempts to force enormous amounts of
energy and enormous magnetic fields into small regions of space achieved
not temperatures and conditions needed for fusion, but rather a violent,
unstable plasma. Plasmas stick to magnetic fields and ride them like a
cowboy on a bronco. The electrically charged plasma tore itself apart
before fusion could occur.
"The problem," Gekelman said, "was we didn't understand plasma physics,
and to a large extent, we still don't."
Plasmas are very odd. Remarkably, the temperature in a plasma within a
magnetic field can differ tremendously in different directions.
"Looking one way from one particular spot, it could be a million
degrees, while looking another way it could be only a thousand,"
Gekelman said. "An analogy would be your face is at a million degrees
and your shoulder is freezing."
As they move through oscillating plasma, superheated and energized
plasma waves can transform themselves and can change the properties of
the plasma.
The Earth is too cold for plasmas to exist here naturally. "Plasmas
start above the Earth's atmosphere; a few hundred miles up, it's all
plasma," Gekelman said. "From then on out, the whole solar system is
filled with plasma."
The Department of Energy and the National Science Foundation have
initially funded the facility for five years. The predecessor to this
machine was funded by the U.S. Navy. In addition to the $4.8 million to
fund the UCLA national user facility, Gekelman's research team has been
funded $600,000 annually from the Department of Energy and the U.S. Navy
to support their own research.
Gekelman, who has conducted research in plasma physics since earning his
Ph.D. in 1971, built several earlier, less sophisticated devices for
studying the behavior of plasmas.
Gekelman's team includes research scientists Jim Maggs, David Leneman
and Steve Vincena; technician Marvin Drandell; and Karen McBride,
associate director of the Basic Plasma Science Facility.
In addition to conducting research and teaching, Gekelman has built the
country's only plasma physics laboratory for high school students, with
funding from another DOE grant. Students and their teachers from some
two dozen Los Angeles-area high schools conduct plasma physics
experiments in this laboratory. Any high school can participate.
"The high school students use the same techniques we do, the same
software and much of the same equipment (but not the new LAPD)," said
Gekelman, who has worked with high school students in his lab for
several years.
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