(Color) The Omega halfraum experimental arrangement and a typical streaked image of the interferometer fringe pattern. Shock breakout at the Al/vacuum interface is in upper half of the streak. Shock breakout at the Al/quartz interface followed by reflection from the shock front within the quartz is in the lower half of the streak.
(Color) Velocity-time unfolds of dual interferometer fringe patterns with two different velocity per fringe optical delay settings.
(Color) (a) The upper image is an interferometer streak in which the transit times for shock propagation across the aluminum step and the quartz sample are clearly discernible. (b) The lower image is a SOP streak (of the same experiment) in which the shock thermal luminescence can be used to verify the shock transit times. In both images, the time fiducials are at intervals.
(Color) (a) Dante temperature history unfolds for experiments with Hohlraum temperatures covering the range of . (b) Interferometer measurements of the quartz shock velocities for these same experiments.
(Color) (a) The empirical scaling has been applied to the velocity-time plots shown in Fig. 4(b) and then overlaid on the Dante plots of Fig. 4(a). The time shift correction has been applied to the velocity interferometer-determined temperatures and then overlaid on the Dante plots. The additional plot covering the midrange temperatures is from an experiment in which only the quartz component was used (i.e., no aluminum step).
(Color) As the Hohlraum temperature is increased (via increasing the laser input power and intensity), the problem of preheat ahead of the shock increases. This results in a loss of optical transparency in the quartz and, hence, a “blanking” of the data in the interferometer streaked image. Interestingly, it appears that the optical transparency of the quartz recovers after the end of the laser pulse (especially in the upper image).
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