Target diagram. In this view the backlighter plate would sit directly behind target, below the plane.. When the VISAR (velocity interferometer system for any reflector) diagnostic was used (see the text for reference), additional arms were added to hold a quartz window and a mirror for the VISAR laser, and shielding was added behind the drive disk and to the left of the arms to reduce preheating of the gas in the arms. When a point backlighter was used, its line of sight was in the same direction as the VISAR line of sight.
(Color online) Radiography image from an area backlighter, at , from an experiment with a polyimide drive disk attached to a polyimide tube of i.d., irradiated with SSD at onto a laser spot. The illumination was by x rays from V produced by overlapping six laser beams. The grid with a fiducial feature establishing an absolute location is evident in the lower part of the figure. The wall of the tube can be seen near the upper edge.
(Color online) Radiography image from a point-projection backlighter, or a “backlit pinhole,” from an experiment with a drive disk attached to a polyimide tube of i.d., irradiated with SSD at onto an laser spot, again using a V backlighter. The same type of fixed spatial fiducial is present, as are the tube walls. The shock is tilted in the plane of the image, but some evidence of trailing xenon along the tube walls is present.
(a) Density vs position from two Hyades simulations, at , for experiments at a laser intensity of . The boundaries between the drive plasma, in this case Be, and the xenon are shown, labeled “contact surfaces.” The solid line shows the result for multigroup, diffusive radiation transport, whereas the dashed line shows the result for a nonradiative system. When radiation is suppressed (dashed line), a collapsed layer does not form. (b) Density and temperature vs position from the Hyades simulation with radiation transport at . The solid line is mass density, the dashed line is ion temperature, and the dash-dotted line is electron temperature. Note the difference in scales between (a) and (b).
(Color online) (a) Density profile at , from a 2D simulation of the experiment, using the FCI code. The shock is moving to the right. The color bar calibrates the density as a ratio to the initial gas density. (b) Simulated radiograph, using density data from (a). Poisson noise and a point-spread function from data are included.
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