This volume of the LLE Review includes an article on the status of the optics on the OMEGA laser system after the first 18 months of operation. A vigorous program to monitor the performance of the optics has been followed since the inception of the OMEGA laser. The article presents results from these observations and defines the various types of possible damage. Many of the optics have not damaged, such as the frequency-conversion crystals, polarizers, calorimeters, and liquid crystal optics. The most significant damage has been sustained by the fused-silica spatial filter lenses. There has been no evidence of any propagation of damage downstream of damage optics. Other highlights of research presented here are: The development of a single-beam, ponderomotive optical trap for energetic free electrons. A description of the new diode-pumped Nd:YLF master oscillator for the OMEGA laser. Simulations of heat transfer from localized absorbing defects to the host coating material in HfO{sub 2}/SiO{sub 2} 351-nm high reflectors. An experimental study of target performance and mixing in titanium-doped target implosions on OMEGA. A theoretical calculation of the dephasing time of an electron accelerated by a laser pulse. Separate abstracts have been indexed into the energy database from articles in …

This volume of the LLE Review, covering the period October-December 1996, includes a review of 2-D SSD as implemented on the OMEGA laser system. A summary of the detailed mathematical formalism is shown, and the predicted level of uniformity achievable on OMEGA is given. The first experimental results on uniformity using narrow-band 2-D SSD are compared to theoretical calculations. Excellent agreement between experiment and theory is found, which gives confidence that broadband 2-D SSD with polarization wedges should achieve an rms nonuniformity in the 1%-2% level necessary for cryogenic implosion experiments.

This volume of the LLE Review, covering the period April-June 1997, includes an article discussing the results from recent experiments performed on OMEGA. These experiments used a new beam-smoothing device-distributed polarization rotators-in concert with existing techniques to improve the on-target uniformity of each beam. The result of this improved radiation uniformity was a substantive reduction in imprinting-the nonuniformity caused by the laser. A novel way to study the time dependence of this imprinting is also presented in this article.