Soft x-ray power diagnostics are essential for measuring the total x-ray flux, radiation temperature, conversion efficiency, and albedo that define the energetics in indirect and direct drive, as well as other types of high temperature laser plasma experiments. A key diagnostic for absolute radiation flux and radiation temperature in hohlraum experiments is the Dante broadband soft x-ray spectrometer. For the extended range of x-ray fluxes predicted for National Ignition Facility (NIF) compared to Omega or Nova hohlraums, the Dante spectrometer for NIF will include more high energy (<2 keV) edge filter band-pass channels and access to an increased dynamic range using grids and signal division. This will allow measurements of radiation fluxes of between 0.01 to 100 TW/sr, for hohlraum radiation temperatures between 50 eV and 1 keV. The NIF Dante will include a central four-channel imaging line-of-sight to verify the source size, alignment as well as checking for any radiation contributions from unconverted laser light plasmas.

The diagnostic instrument manipulator ͑DIM͒ provides a diagnostic platform to insert and retract a variety of instruments into and out of the National Ignition Facility target chamber. The DIM is a two-stage telescoping system, designed to fit on any of the DIM designated diagnostic ports on the target chamber, and will provide precision radial positioning, pointing, and alignment-to-target capability. The DIM provides a standard set of utilities, and cables to support the operation of instruments that require insertion into the target chamber. The DIM provides for positioning of diagnostic packages, and enables exchange of manipulator diagnostics between fusion laboratories. Principal design requirements for the DIM are presented. A half-length prototype of the DIM was designed and fabricated by Atomic Weapons Establishment in England and is being tested at Lawrence Livermore National Laboratory. The results of this testing are presented.

Two static x-ray imagers (SXI) will be used to monitor beam pointing on all target shots in the National Ignition Facility. These pinhole-based instruments will provide time integrated two-dimensional images of target x-ray emissions in the energy range between 2 and 3 keV. These instruments are not DIM based and will view along dedicated lines of sight from near the top and bottom ports of the target chamber. Beams that miss or clip the hohlraum laser-entrance holes will produce x-ray emission on the ends of the hohlraum, indicating improper beam pointing and/or target positioning. The SXIs will also be used to quantify beam focusing and pointing by producing x-ray images of dedicated test targets irradiated by focused beams at precalculated positions. A proposed design is presented, along with supporting data from NOVA target experiments.

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