Tokamak

The word “tokamak” is said to be a contraction of the Russian words for current (t o k), vessel (k a m e p), magnet (m a Γ h t), and coil (k a t y k a). Tokamaks are axisymmetric, with the plasma current itself giving rise to the poloidal field essential to the equilibrium of toroidal plasmas. In a tokamak, the toroidal field used to stabilize against MHD instabilities is strong enough to satisfy the Kruskal-Shafranov condition. This characteristic is quite different from that of reversed field pinch, with its relatively weak toroidal field. There are reviews and textbooks of tokamak experiments and theory [4.1],[4.2],[4.3] and diagnostics [4.4].