1999

LLE CEA Collaboration
LLE began a long-standing collaboration with the Military Applications Division of the French Atomic Energy Commission (La Direction des applications militaires du Commissariat à l’énergie atomique et aux énergies alternatives, CEA). Their collaboration has produced scientific results ranging from improved understanding of laser–plasma interaction to high-resolution neutron imaging diagnostic development.

Cryogenic Target Handling System
LLE integrated the OMEGA Cryogenic Target Handling System into the OMEGA facility.

Target Designs for the National Ignition Facility (NIF)
LLE developed moderate-gain, direct-drive designs for the NIF.

Moving Cryostat
The moving cryostat maintains a target at a constant temperature to layer the DT ice and transports the target to the center of the target chamber. The cryostat base is shown. At the bottom is the cryo cooler. Above the cooler are the four-axis positioner and two thermal shrouds that are maintained at 45 K and 16 K. The target assembly is at the top. The target is mounted on spider silk in a C-shaped beryllium support.

NIF Deformable Mirror
The NIF deformable mirror will allow wavefront correction of the NIF beam when the 39 posts on the back of the mirror are bonded to actuators on a reaction block. LLE will be coating the substrates with a low-stress, dielectric high reflector and assembling the deformable mirrors for Lawrence Livermore National Laboratory (LLNL).

Two-Dimensional Smoothing by SSD
A two-dimensional smoothing by spectral dispersion (2D SSD) system was installed on OMEGA, capable of producing phase-modulated spectra that can be frequency tripled to 1-THz bandwidth in the ultraviolet. This 2D SSD system incorporated a high-frequency bulk-phase modulator operating at 0.4 GHz to produce 11 Å of bandwidth in the infrared.

Efficient frequency tripling of this broadband signal requires dual-tripler frequency-conversion crystals that are currently installed on only 13 beams. The high-frequency bulk-phase modulator can also be operated at 3 Å with a higher dispersion grating to produce three SSD color cycles, which significantly improves beam smoothing at lower bandwidths on all 60 OMEGA beams.