A transliterated Russian word for an assembly for producing nuclear fusion. It consists essentially of a doughnut-shaped evacuated chamber called a torus, of 18-inch cross section, through which the plasma moves. Surrounding the torus is an electromagnetic field powerful enough to confine the energized plasma sufficiently to achieve the required density of 1014 particles/cc/sec and a temperature well above 44 million centigrade. Up to 74 million centigrade has been obtained experimentally, but 100 million centigrade will be necessary for power production. The vacuum chamber and the magnetic field simulate conditions on the sun, i.e., absence of air and immense gravitational forces. Several experimental tokamaks are in operation in the U.S., the largest being at Princeton, NJ. It is utilizing hydrogen and deuturium as a test plasma and thus can attain temperatures of only 100,000C. After further experimentation and modification, it should be capable of reaching the 100 million centigrade necessary for power production when tritium is used.See Fusion.
