 |
| First
Achievement of Fusion Temperature
in a Laboratory (PLT) Princeton
Large Torus |
Plasma science (the study of ionized
gases) is critical to the development
of fusion energy (involving the fusion
of nuclei), which could be an abundant
and attractive energy source in the
future. Scientists at Princeton Plasma
Physics Laboratory achieved ion temperatures
in excess of 58,000,000 oC,
the minimum required for a self-sustaining
fusion reaction (a condition called
ignition), for the first time in 1978.
These experiments required a number
of advances, most importantly in the
development of a powerful new technique
for heating a magnetically confined
plasma-neutral beam heating. The use
of neutral beams to heat plasma dates
back to the early 1960s with work
performed at the Lawrence Livermore
and Oak Ridge national laboratories.
Neutral beam heating involves the
injection of high currents of energetic
neutral atoms into the plasma. The
neutral atoms cross the magnetic confinement
field and enter the plasma, where
they are ionized and confined by the
magnetic field. They then heat the
plasma through collisions with the
plasma ions and electrons. Oak Ridge
supplied the neutral beam heating
systems used in the Princeton experiments.
Scientific Impact:
Neutral beam heating paved the way
for major advances in the next generation
of plasma confinement devices, which
attained ion temperatures suitable
for practical fusion energy production
and multi-megawatt fusion power levels.
It is believed that practical fusion
power production will require plasma
temperatures in the range of 100,000,000
oC
to 200,000,000 oC.
Social Impact: This
advance helped lay the groundwork
for promoting fusion as an attractive
energy source. In addition to the
general public, beneficiaries may
include industries that use plasma
science and technology, including
makers of semiconductors and space
propulsion systems.
Reference: "Neutral-beam-heating
results from the Princeton Large Torus,"
H. Eubank, R. Goldston, V. Arunasalam,
M. Bitter, ..., Phys. Rev. Lett.
43, 270 (1979).
Technical Contact:
John Willis, Research Division, 301-903-4095
Press Contact: Jeff
Sherwood, DOE Office of Public Affairs,
202-586-5806
SC-Funding Office:
Office of Fusion Energy Sciences |
