A high-power CH3F laser for plasma diagnostics

A high-power, optically pumped, methyl fluoride laser operating at 496 μm has been developed for plasma diagnostic applications. An output power of 100 mW has been measured directly on a calorimeter. The high-pump power utilized in this experiment has also allowed the first observation of saturation in far-infrared output power resulting from severe vibrational bottlenecking. The effect of buffer gases in relieving this bottlenecking is described and compared to a simple rate-equation model     

Plasma diagnostic applications on the TEXT tokamak using a high power,twin frequency optically pumped far-infrared laser

A high-power, twin-frequency, optically-pumped, far-infrared (FIR) laser has been developed at UCLA for diagnostic application on the TEXT tokamak. The source is operated at 245 GHz (λ=1.22 mm) for heterodyne scattering measurements and 694 GHz (λ=432 μm) for high resolution interferometry. Future plans include a 30 channel interferometer/polarimeter operating at 694 GHz to accurately determine current profiles.     

High-resolution monochromatic x-ray imaging system based on spherically bent crystals

We have developed an improved x-ray imaging system based on spherically curved crystals. It is designed and used for diagnostics of targets ablatively accelerated by the Nike KrF laser. A spherically curved quartz crystal (d = .?, R = mm) has been used to produce monochromatic backlit images with the He-like Si resonance line (1865 eV) as the source of radiation. The spatial resolution of the x-ray optical system is 1.7 mum in selected places and 2-3 mum over a larger area. Time-resolved backlit monochromatic images of polystyrene planar targets driven by the Nike facility have been obtained with a spatial resolution of 2.5 mum in selected places and 5 mum over the focal spot of the Nike laser.     

The NIKE KrF laser fusion facility

NIKE is a second generation high power KrF laser now under construction at the Naval Research Laboratory. The project is a collaborative effort between NRL and Los Alamos National Laboratory. NIKE is designed to deliver more than 2 kJ of energy to target in a 600-m focal spot and a 4-ns pulse duration. Echelon free induced spatial incoherence (ISI) will be used to produce uniform target illumination. Flat targets will be ablatively accelerated to study both Rayleigh-Taylor and parametric instabilities. These results will have direct implications to direct-drive inertial confinement fusion for commercial energy applications. Reliable operation of a high power KrF laser is also an important goal of the NIKE laser, with the objective of 1000 target shots per year. This would be an important step in the development of the KrF laser as an ICF driver. NIKE is cheduled to begin target experiments in early 1994. If successful, these experiments will provide a technical basis to proceed with construction of an ignition facility.