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The goals of the recently activated Nova laser facility are to address critical issues for evaluating the feasibility of inertial confinement fusion, to implode DT to densities exceeding 200 g/cm3 and pressures greater than 1011 atm, and to perform a wide range of high energy density plasma physics experiments in the areas of XUV/x-ray lasers, hydrodynamics, and radiation generation and transport. An extremely flexible and sophisticated facility is required to successfully perform such a variety of tasks. The ten-arm Nova laser is capable of irradiating complex targets with laser wavelengths of 0.53 and 0.35 μm and pulse widths that range from 0.09 to >5 ns, and peak powers greater than several terrawatts per beam line. A sophisticated, variable impedance, transmission line driven Pockels cell allows for complex temporal shaping of the laser pulse. Synchronized oscillators allow for different pulses to be propagated down the beam lines for experiments that require long-pulse or short-pulse x-ray backlighting. The output of the laser can be directed into two independent target areas: a 4.4-m-diam vacuum vessel for experiments which require 10 beams, and a 1.8-m-diam chamber for two Nova arms. The facility has been designed to allow nearly simultaneous, independent experiments to be conducted in both target areas. A number of sophisticated optical, XUV, x-ray, and particle diagnostics measure target performance. An optical fiducial system allows cross correlation of all of the diagnostic systems to better than 50 ps. An overview of the facility, diagnostics, and data-acquisition system will be discussed.

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The National Ignition Facility (NIF) is the world's largest optical instrument, comprising 192 37 cm square beams, each generating up to 9.6 kJ of 351 nm laser light in a 20 ns beam precisely tailored in time and spectrum. The Facility houses a massive (10 m diameter) target chamber within which the beams converge onto an ∼1 cm size target for the purpose of creating the conditions needed for deuterium/tritium nuclear fusion in a laboratory setting. A formidable challenge was building NIF to the precise requirements for beam propagation, commissioning the beam lines, and engineering systems to reliably and safely align 192 beams within the confines of a multihour shot cycle. Designing the facility to minimize drift and vibration, placing the optical components in their design locations, commissioning beam alignment, and performing precise system alignment are the key alignment accomplishments over the decade of work described herein. The design and positioning phases placed more than 3000 large (2.5 m×2 m×1 m) line-replaceable optics assemblies to within ±1 mm of design requirement. The commissioning and alignment phases validated clear apertures (no clipping) for all beam lines, and demonstrated automated laser alignment within 10 min and alignment to target chamber center within 44 min. Pointing validation system shots to flat gold-plated x-ray emitting targets showed NIF met its design requirement of ±50 μm rms beam pointing to target chamber. Finally, this paper describes the major alignment challenges faced by the NIF Project from inception to present, and how these challenges were met and solved by the NIF design and commissioning teams.

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