DESIGN DESCRIPTIONS OF THE PROMETHEUS-L AND PROMETHEUS-H INERTIAL FUSION ENERGY DRIVERS

Two innovative drivers have been designed for a prototype 1000 MW ther monuclear power plant planned for operation early in the next century. The Prometheus-L driver is a 4 MJ KrF master oscillator power amplifi er laser system designed to operate at a 5.6 Hz repetition rate. Outpu t pulses from the KrF master oscillator are synchronized with the puls ed-power excitation of the KrF power amplifiers and the launching of t he inertial fusion energy (IFE) deuterium/tritium targets. The Prometh eus-L laser architecture features 960 5 kJ electric discharge KrF powe r amplifiers pumping 60 crossed stimulated rotational Raman scattering H-2 amplifiers serving as beam accumulators. Pulse compression of the 60 accumulator beams is accomplished in 60 chirped, self-seeded SF6 s timulated Brillouin scattering pulse compressors. Grazing incidence me tal focusing mirrors minimize back-streaming radiation damage from the target chamber. This architecture permits the laser driver to; delive r spectrally broad-band, temporally complex optical pulses in 60 beam lines to implode the direct-drive IFE targets within a 5 m radius targ et chamber. The Prometheus-H driver is a 7.8 MJ 4 GeV Pb++ heavy ion ( HI) inertial fusion energy system designed to operate at a 3.5 He repe tition rate. The HI driver design is based on a short, ramped gradient , 5 MeV accelerator, followed by a longer, 2 km constant gradient, sin gle beam linear accelerator operated in a 50 kHz burst mode to generat e sequentially 18 4 GeV beamlets. A two-sided irradiation geometry was developed for indirect-drive HI targets. Six beamlets are used for th e 45 ns precursor HI pulses stored in two superconducting storage ring s, 12 superconducting storage rings accumulate the 12 main beamlets, w ith a final buncher generating the 8 ns HI pulses which arrive at the target chamber simultaneously. Final focusing is accomplished with lar ge aperture triplet focusing magnets through Pb-vapor neutralization c ells lo reduce the effect of space charge, ballistically focusing onto two Pb stripping jets to create self-pinched Pb+82 beams which propag ate along two preformed channels through two small openings in the HI target chamber blanket.