IGNITOR Physics Assessment and Confinement Projections

An independent assessment of the physics of Ignitor is presented. Ignitor is a physics demonstration experiment, with the main goal of achieving thermonuclear ignition, defined as the regime where fusion alpha heating compensates for all forms of energy losses. Simulations show that a pulse of α particle power up to 10-20 MW is produced for a period over a few seconds. Crucial issues are the production of peaked density profiles on a time-scale of several energy confinement times, the control of current penetration for the optimization of ohmic heating and sawtooth avoidance. The presence of a 10-20 MW Ion Cyclotron Radio frequency system and the operation of a high-speed pellet injector are considered essential to provide added flexibility in order to counter unexpected, adverse plasma behavior.