Direct-Drive Cryogenic Target Implosion Performance on OMEGA
OAK-B135 Layered and characterized cryogenic D2 capsules have been imploded using high-contrast pulse shapes on the 60-beam OMEGA laser at the Laboratory for Laser Energetics [T. R. Boehly et al., Opt. Commun. 133, 495 (1997)]. These experiments measure the sensitivity of the direct-drive implosion performance to parameters such as the inner-ice-surface roughness, the adiabat of the fuel during the implosion, and the laser power balance. The goal is to demonstrate a high neutron-averaged fuel rR with low angular variance using a scaled, a {approx} 3 ignition pulse shape driving a scaled all-DT ignition capsule. Results are reported with improvements in target layering and characterization and in laser pointing and target positioning on the OMEGA laser over previous experiments [T. C. Sangster et al., Phys. Plasmas 10, 1937 (2003)]. These capsules have been imploded using up to 23 kJ of 351-nm laser light with an on-target energy imbalance of less than 2% rms, full beam smoothing (1-THz bandwidth, two-dimensional smoothing by spectral dispersion, and polarization smoothing), and new, optimized, distributed phase plates. Pulse shapes include high-adiabat ({approx}25) square pulses and low-adiabat (<5) shaped pulses. The data from neutron and charged-particle diagnostics, as well as static and time-resolved x-ray images of the imploding core, are compared with one- and two-dimensional numerical simulations. Scaling of target performance to a weighted quadrature of inner-ice roughness at the end of the acceleration phase is investigated.
- Research Organization:
- Laboratory for Laser Energetics (US)
- Sponsoring Organization:
- (US)
- DOE Contract Number:
- FC03-92SF19460
- OSTI ID:
- 823149
- Report Number(s):
- DOE/SF-19460-531; 1441; 2003-129; TRN: US0401667
- Journal Information:
- Physics of Plasmas, Vol. 11, Issue 5; Other Information: Submitted to Physics of Plasmas: Volume 11; No.5; PBD: 27 Apr 2004
- Country of Publication:
- United States
- Language:
- English
Similar Records
Direct-drive, cryogenic target implosions on OMEGA
Improved Performance of Direct-Drive Inertial Confinement Fusion Target Designs with Adiabat Shaping Using an Intensity Picket