The DIM imaging streak camera. The x-ray signal enters the instrument through the photocathode slit, where it is converted to secondary electrons. The electron signal is extracted from the photocathode by applying a voltage gradient across the photocathode and mesh: the electrons are then focused and deflected on to the MCP.
DISC EMI shield consisting of: (a) an Al shield holder, with vacuum pump-out holes used to maintain vacuum inside of the streak tube.8 (b) A 750 LPI Ni mesh, which transmits 55% of incident x-ray photons, is supported by a stainless steel holder.
A sample streaked radiography image of an imploding convergent ablator capsule, recorded with DISC 3. A time history of the final phase of the imploding capsule shell is shown, the implosion phase occurs at early times (bottom) and capsule self-emission at a later time (top). A set of six UV pulses, separated by ∼300 ps, are shown on the left.
(a) Line spread function (in spatial direction) and Gaussian fit. (b) Contrast transfer function.
(a) Sample dynamic range image; a lineout is taken across the central slit region, within the central dashed box and the lineout is fitted with a Gaussian. The resulting FWHM is plotted as a function of average number of counts in the 50% transmission region shown in the left and right solid boxes. (b) Resulting plot generated from data collected with DISC3 on the 5 ns sweep speed and medium gain, the dashed line marks the onset of saturation, where the FWHM broadens by 20%.
A demonstration of the warp correction transformation. The image is generated using a spatially and temporally calibrated pulse train. The recorded raw pulse locations are shown in red squares, and the corrected pulse locations are shown in blue circles. The warp transformation applies a shift to the raw image to bring the pulses to their expected calibrated locations in space and time (approximated by grid).
Percent degradation in the yield signal from a 2000 Å thick CsI cathode as a function of air exposure time.
Summary of DISC calibration tests for DISC 1, 2, and 3. The temporal resolution values correspond to a medium intensifier gain setting, a 250 μm slit width, and 2 ns sweep speed. The dynamic range values are provided for the 5 ns sweep.
Summary of DISC measured sweep window lengths.
Detector efficiency of DISC when using an Au and CsI photocathode at 8.5 keV. Detector efficiency is defined as photons detected per incident photon and incident sensitivity is defined as counts per incident photon, respectively.
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