Progress in direct-drive inertial confinement fusion

David D. Meyerhofer
2004 Frontiers in Optics 2004/Laser Science XXII/Diffractive Optics and Micro-Optics/Optical Fabrication and Testing   unpublished
Significant progress in direct-drive inertial confinement fusion ͑ICF͒ research has been made since the completion of the 60-beam, 30-kJ UV OMEGA Laser System ͓Boehly, Opt. Commun. 133, 495 ͑1997͔͒ in 1995. A theory of ignition requirements, applicable to any ICF concept, has been developed. Detailed understanding of laser-plasma coupling, electron thermal transport, and hot-electron preheating has lead to the measurement of neutron-averaged areal densities of ϳ200 mg/ cm 2 in cryogenic target
more » ... n cryogenic target implosions. These correspond to an estimated peak fuel density in excess of 100 g / cm 3 and are in good agreement with hydrodynamic simulations. The implosions were performed using an 18-kJ drive pulse designed to put the converging fuel on an adiabat of two. The polar-drive concept will allow direct-drive-ignition research on the National Ignition Facility while it is configured for indirect drive. Advanced ICF ignition concepts-fast ignition ͓Tabak et al., Phys. Plasmas 1, 1626 ͑1994͔͒ and shock ignition ͓Betti et al., Phys. Rev. Lett. 98, 155001 ͑2007͔͒-have the potential to significantly reduce ignition driver energies and/or provide higher target gain.
doi:10.1364/fio.2004.ftun1 fatcat:sbifqvmldvd7hmd24qiotenafi