(left) XRSA cassette shown being inserted through a mock-up of the DIM side-access panel, showing the space-envelope constraints that allow changes of cassettes between NIF shots. (right) The XRSA cassette in the space envelope of the DIM.
Exploded view of one of the eight samples holders or “paddles” in the XRSA cassette. The sample is held in a receptacle in the back side of the paddle-shaped part in the middle of the figure. Filter frames with both single and triple-exposure apertures are shown, although only one type of filter frame was fielded in front of a sample on any shot.
Rear view of the spacer with the line contact that separates the sample from the filters and keeps the sample in minimal contact with the sample-holder structure. The diameter of the round end of the paddle is 63 mm; the diameter of the sample receptacle is 40 mm.
(left) Exploded view of a square sample holder and (right) front view of an assembled paddle with the sample surface and the inner edge of the spacer visible in the square aperture.
Layout of an assembled cassette with sample positions having the various required apertures.
(left) Front and (right) rear views of the XRSA cassette, populated with samples and ready for the filter frames and collimators (Sec. II B) to be attached.
Drawing of an assembled XRSA cassette with filter frames and collimators attached. The cassette is mounted on the rails that connect the cassette to the DIM cart. Also shown is the removable pointer that is used to position the assembly before a shot (see Sec. II D).
Filter materials installed in filter frames and ready for assembly onto the face of the XRSA cassette.
Assembled and aligned (Sec. II C) XRSA cassettes ready for mounting on the DIM rails.
(a) XRSA cassette with laser pointer attached to extension arms, (b) adjustment of the collar on the back of the cassette to change the tilt of the paddles, and (c) laser beam aligned to the tooling ball on the end of the pointer.
OPAS image of XRSA cassette mounting nut, which measures 27.22 mm corner to corner. The circle reticule is set on the operator’s screen at . The DIM alignment is then moved until the nut’s image best matches the circle template.
(left) CIVS reference image taken with the polar CIVS wide-field camera during XRSA-cassette alignment procedures. (right) Chamber view of XRSA cassettes aligned moments before a shot. The samples are in DIMS at (bottom) and (90,315) (left), and the TARPOS with the laser target enters the chamber from a port at (90,239) (top).
(left) A photograph of a thick Kapton film used as a rear filter in the XRSA cassette, and (right, top) a photomicrograph at and (bottom) magnification of some of the observed particulate debris.
Postshot view of samples in the cassette showing the square and round samples. For this shot, the round sample positions had a mixture of single and triple exposure regions for various samples.
(left) Preshot picture of a test specimen and (right) postshot exposed sample from shot N091111-001-999 (cassette serial number 14150030 in DIM 9-45, position 3), which was positioned at a sample-to-TCC stand-off distance of 38 cm.
Table of important dimensions for components of the XRSA cassette. Masses are determined without samples in the receptacles.
NIF shot numbers and the sample-to-source stand-off distances (SODs) for XRSA cassettes operated in NIF’s two equatorial DIMs located at target-chamber coordinates (90,45) and (90,315).
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