Schematic of the experimental setup. The Hohlraum axis is tilted 19° to the SXI image. (a) Sketch of Hohlraum showing laser beams (on outside) and HYDRA (Ref. 3) simulation of electron temperature (on inside). The places where the beams hit the wall at early time are identified. Not shown is the trajectory of the laser beams inside the Hohlraum. One outer beam is shown as dashes to illustrate that a high-Z bubble is formed where the outer beams hit the wall. (b) Typical SXI image: the red arrow connects the feature in the SXI image to the high-Z bubble. The white arrow connects an inner beam feature in the SXI image to the spots where the inner beams hit the Hohlraum wall.
SXI CCD vs x-ray energy: (a) quantum efficiency (QE), (b) CCD response: counts or DN per photon per pixel, and (c) response of the 3–5 keV channel.
Identification of features in the SXI image.
Lineouts: (a) horizontal lineout (black) and radial distribution function (red) used to obtain the size of the LEH. (b) Vertical lineout (black) from the 2D image in Fig. 5(b) and from the simulation (blue) in Fig. 5(c). The fluence in the outer beams is the average counts in the region between the dashed red lines (which show the full width at 70% maximum in the outer beam feature.)
Comparison to modeling: (a) SXI data image, (b) 2D version of data (with 0 mm wall motion on left half and 0.3 mm wall motion on right half), and (c) 2D LASNEX (Ref. 7) simulation. The vertical lineouts from (b) and (c) are plotted in Fig. 4(b). The white dashed circles show the original size of the LEH. The yellow dashed circles show the clear aperture (final size of the LEH). The simulation show similar counts in features [Fig. 4(b)] but the clear aperture is smaller. Note that the far inner beams are distinct in the data but are mixed with the near beam feature in the simulation.
Evidence of energy transfer from outer beams to inner beams with increasing . (a) The average counts in the outer beams decrease and increases. (b) The symmetry of capsule goes from prolate to round as increases.
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