Small Tight Aspect Ratio Tokamak
The Small Tight Aspect Ratio Tokamak, or START was a nuclear fusion experiment that used magnetic confinement to hold plasma. START was the first full-sized machine to use the spherical tokamak design, which aimed to greatly reduce the aspect ratio of the traditional tokamak design.
| Small Tight Aspect Ratio Tokamak | |
|---|---|
| Device type | Spherical tokamak |
| Location | United Kingdom |
| Affiliation | Culham Centre for Fusion Energy |
| History | |
| Year(s) of operation | 1990–1998 |
| Succeeded by | Mega Ampere Spherical Tokamak (MAST) |
The experiment began at the Culham Science Centre in the United Kingdom in 1990 and was retired in 1998. It was built as a low cost design, largely using parts already available to the START team. The START experiment revolutionized the tokamak by changing the previous toroidal shape into a tighter, almost spherical, doughnut shape. The new shape increased efficiency by reducing the cost over the conventional design, while the field required to maintain a stable plasma was a factor of 10 less.