Exploration of burning plasmas in FIRE

The Fusion Ignition Research Experiment (FIRE) design study has been undertaken to define the lowest cost facility to attain, explore, understand and optimize magnetically-confined fusion-dominated plasmas. FIRE activities have focused on the physics and engineering assessment of a compact, high-field tokamak with the capability of achieving Q greater than 10 in the Elmy H-mode for a duration of about 2 plasma current redistribution times (τcr) during an initial burning plasma science phase. The configuration chosen for FIRE is similar to that of ARIES-RS, the U. S. Fusion Power Plant study utilizing an advanced tokamak reactor. The reference design point is: Ro=2.14m, a=0.595 m, Bt(Ro)=10T, Ip=7.7MA with a flat top time of 20 s (about 1.7 τcr) for 150 MW of fusion power. FIRE will utilize only metal plasma facing components; Be coated tiles for the first wall and W brush divertors to reduce tritium retention as required for fusion reactors. A longer term goal of FIRE is to explore advanced tokamak regimes with bootstrap fractions (fBS) about 70% at τcr about 3.5 at high fusion gain (Q greater than 5) for a duration of 1 to 3 τcr. (author)