Heavy Ion Beam Transport in ICF Reaction Chambers

Abstract

An analysis has been performed to determine the technological requirements for transporting a beam of heavy ions across an inertial confinement fusion (ICF) reaction chamber. This is a crucial issue because excessive beam expansion will reduce the driver energy deposited on the target and degrade the performance of the reactor system. The physical mechanisms that dominate beam expansion for heavy-ion fusion applications include emittance growth, instabilities, parallel momentum spread, and space charge. These mechanisms place technological constraints on such system parameters as beam voltage, beam power, number of beams, beam mass and charge state, final transport length, beam port radius, target radius, beam emittance, momentum tilt, and background chamber gas density. The economic analysis of a heavy-ion ICF reactor system requires a thorough understanding of the trade-offs among these parameters imposed by the beam expansion mechanisms.