Short-wavelength, direct-drive laser fusion experiments at the Laboratory for Laser Energetics

Conference · Sun Jan 01 04:00:00 EST 1984

OSTI ID:5595456

McCrory, R L; Barnouin, O; Craxton, R S; Delettrez, J; Epstein, R; Forsley, L; Goldman, L M; Hutchison, R J; Keck, R L; Kim, H

Measurements are reported of absorption, hot electron generation, preheat, thermal transport and irradiation uniformity in direct-drive, spherical target experiments conducted with six 351-nm wavelength beams of the OMEGA symmetric irradiation facility. On-target energy in excess of 400 J, pulses of 650 ps duration and uniform irradiation at an intensity in the range of 10/sup 13/ to 10/sup 15/ W/cm/sup 2/ characterize the laser conditions for these experiments. Absorption varied from 100%, for Ti targets at an intensity of 10/sup 13/ W/cm/sup 2/, to 60% at an intensity of 2 x 10/sup 15/ W/cm/sup 2/. The suprathermal electron fraction was found to be less than 3 x 10/sup -3/ of the absorbed energy in these experiments. Higher ablation pressures were measured than in comparable 1054-nm experiments. At a laser intensity of 10/sup 15/ W/cm/sup 2/ an ablation pressure of 100 Mbar was deduced from plasma blowoff measurements. Measurement and calculation of the irradiation uniformity indicate that the 24 beam OMEGA, 351-nm laser should be capable of producing the required drive uniformity to compress targets to 200 times liquid DT density with less than 2000 joules of laser energy.

• Research Organization: Rochester Univ., NY (USA). Lab. for Laser Energetics
• DOE Contract Number: AC08-80DP40124
• OSTI ID: 5595456
• Report Number(s): DOE/DP/40124-70; IAEA-CN-44/D-1-1; CONF-840910-28; ON: DE85014411
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700208* -- Fusion Power Plant Technology-- Inertial Confinement Technology
ABSORPTION
CONFIGURATION
DEUTERIUM TRITIDE
ENERGY TRANSFER
IRRADIATION
LASER TARGETS
OMEGA FACILITY
SPHERICAL CONFIGURATION
SYMMETRY
TARGETS