Fusion Science and Technology / Volume 43 / Number 1 / January 2003 / Pages 1-17
The design of a reduced size (R = 4.45 m, BT = 5.04 T) ignition tokamak (Q = ) with superconducting coils using a standard ELMing H-mode plasma appears to be feasible. This effective size (BT2/3R5/6) is smaller than current proposals for Q = 10 burning (D-T) plasma experiments. The good confinement required for ignition with this small effective size is obtained by operating along a gyroBohm scaling path starting from the existing tokamak database at high beta ( = 4.1%) so that the loss power from core transport exceeds the H-mode threshold power. Using a design that can achieve a high normalized current (Ip /aBT = 1.63) also helps to decrease the size of the machine. The design of this relatively compact ignition tokamak satisfies reasonable engineering constraints on the superconducting toroidal field coils and central solenoid, and allows for a sufficiently long burn time for the plasma current to relax to its final state.