DIII-D (fusion reactor)
|Major radius||1.67 m|
|Minor Radius||0.67 m|
|Magnetic field||2.2 T (toroidal)|
|Plasma current||3.0 MA|
|Location||General Atomics, San Diego, California, United States.|
DIII-D is a tokamak first operated in 1978 and developed in the 1980s by General Atomics (GA) in San Diego, USA, as part of the ongoing effort to achieve magnetically confined fusion. The mission of the DIII-D Research Program is to establish the scientific basis for the optimization of the tokamak approach to fusion energy production.
DIII-D was built on the basis of the earlier Doublet III, the third in a series of machines built at GA to experiment with tokamaks with non-circular plasma cross sections. This work demonstrated that certain shapes strongly suppressed a variety of instabilities in the plasma, which led to much higher performance. DIII-D is so-named because the plasma is shaped like the letter D, a shaping that is now widely used on modern designs, and has led to the class of machines known as "advanced tokamaks". Advanced tokamaks are characterized by operation at high plasma β through strong plasma shaping, active control of various plasma instabilities, and achievement of current and pressure profiles that produce high performance.
DIII-D also pioneered new technology including the use of beams of neutral particles to penetrate the confinement field of the device and heat the plasma within. It achieved several milestones including the highest plasma β parameter ever achieved at the time (early 1980s) and the highest neutron flux (fusion rate) ever achieved at the time (early 1990s). DIII-D continues to be operated by GA, focusing primarily on exploration of the advanced tokamak regime.
The DIII-D Program is a large international program, with more than 90 participating institutions. General Atomics operates the San Diego-based facility for the United States Department of Energy through the Office of Fusion Energy Sciences.
Research in DIII-D aims to elucidate the basic physics processes that govern the behavior of a hot magnetized plasma, and to develop a scientific basis for future “burning plasma” devices such as ITER, a Fusion Nuclear Science Facility and ultimately a fusion power plant. The operation of the DIII-D Tokamak consists of a complex set of systems involving high power, high vacuum, intense lasers, high power RF, high energy beams, cryogenic systems, plasma, and radiation producing equipment.
History of DIII-D at General Atomics
In May 1974, AEC selected General Atomics to build the Doublet III magnetic fusion experiment based on the success of earlier Doublet I and II magnetic confinement experiments. In Feb 1978, Doublet III fusion machine achieved its first plasma conditions at General Atomics. The machine was later upgraded and renamed DIII-D. 
- General Atomics - Magnetic Fusion Energy. "ga.com". Retrieved Nov 30, 2016.
- General Atomics - Nuclear Energy. "ga.com". Retrieved Nov 30, 2016.
- General Atomics History. May 1974 and Feb 1978."ga.com". Retrieved Nov 30, 2016. url=http://www.ga.com/Websites/ga/images/about/history/1974-may.jpg, url=http://www.ga.com/Websites/ga/images/about/history/1978-february.jpg