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The optimization of a 10-kJ large aperture (1-X 1-m) electron-beam-pumped KrF laser is investigated theoretically. Model calculations in zero and one dimension have been performed over extensive ranges in a few parameters for optimization of output fluence. A practical procedure for one-dimensional modeling is given, and significant differences between calculations performed in zero and one dimension are discussed. Predictions are compared to preliminary experimental results. The model is then applied to a regime of much higher electron energy deposition and total gas pressure. Some aspects of the operation of such a laser are discussed. Applications to inertial confinement fusion are described.

Measurements were made of the intrinsic laser efficiency of the KrF excimer laser system as a function of increasing krypton buffer gas at pump rates up to 0.17 MW/cm3. The results show that the la...

Shifts of the line positions of the 2-0 band of HCl perturbed by noble gases, first measured in 1960 [1,2], were later augmented [3-10] by measurements of linewidths and shifts in the pure rotational and rotation-vibration spectra. To explain the experimental results, several theoretical calculations were performed [11-18] that used primarily the Anderson-Tsao-Curnutte (ATC) theory [19,20]. Whereas qualitative agreement with experiment was obtained, the quantitative agreement was poor.

Recently, the Raman effect has been shown to have a profound implication for high power lasers. The implications are both beneficial and deleterious.

The large aperture module (LAM) is the final amplifier of the Los Alamos Aurora krypton fluoride (KrF) laser system.1 Ah artist’s conception of the device is shown in Fig. 1. It consists of a laser chamber with a 1-× 1-m aperture and a 2-m active length which is directly pumped by opposing 1- × 2-m electron beams (up to 675 kV at 20 A/cm2). Each electron gun is driven by two 2.7-Ω water pulse forming lines (PFLs) connected in parallel. The PFLs are each 10.7 m long giving a 650-nsec pump pulse. Each pair of water lines is pulse charged by a Marx generator capable of producing up to 1.8 MV. A pair of Helmholz coils is provided to prevent beam pinching in the diodes and to ensure uniform pumping in the laser gas volume. The laser chamber can be filled with up to 1.5 atm of an Ar/ Kr/F2 lasing mixture.

A series of measurements will be reported in which the intrinsic energy efficiency of the KrF* laser was studied as a function of Kr concentration. A Marx Bank-driven 1-m e-gun device1 was used to produce a 600-nsec 11.4-A/cm2 excitation pulse In the laser cavity. The fluorine density used (0.3 % < [F2] < 0.4%) was chosen to keep the fuel burnup to

Recently, we performed room-temperature extraction1,2 measurements of e-beam-pumped KrF laser mixtures (Ar diluent) containing 4-99.8% Kr. The results demonstrate that Kr-rich mixtures have comparable efficiencies to conventional 4-6% Kr mixtures at high pressures (≥1.7 atm). Improving the performance of the Kr-rich mixtures may be possible by increasing the initial temperature of the medium to reduce Kr2F* formation as originally suggested by Shui.3 The formation of Kr2F reduces gain by quenching KrF* and by absorbing at the laser wavelength.