The dilation aided single–line–of–sight x–ray camera for the National Ignition Facility: Characterization and fielding

Abstract

Crystal x-ray imaging is frequently used in inertial confinement fusion and laser-plasma interaction applications, as it has advantages compared to pinhole imaging, such as higher signal throughput, beer achievable spatial resolution and chromatic selection. However, currently used x-ray detectors are only able to obtain a single time resolved image per crystal. e dilation aided single-line-of-sight x-ray camera described here, designed for the National Ignition Facility (NIF) combines two recent diagnostic developments, the pulse dilation principle used in the dilation x-ray imager (DIXI) and a ns-scale multi-frame camera that uses a hold-andreadout circuit for each pixel (hCMOS). is enables multiple images to be taken from a single-line-of-sight with high spatial and temporal resolution. At the moment, the instrument can record two single-line-of-sight images with spatial and temporal resolution of 35 µm and down to 35 ps, respectively, with a planned upgrade doubling the number of images to four. Here we present the dilation aided single-line-of-sight camera for the NIF, including the x-ray characterization measurements obtained at the COMET laser and the results from the initial timing shot on the NIF.

Investigation of hard x-ray emissions from terawatt laser-irradiated foils at the Matter in Extreme Conditions instrument of the Linac Coherent Light Source

“…As described above, the low-temperature bremsstrahlung spectrum from thermal electrons not only coincides closely with the ∼9 keV quantum efficiency peak for the silicon detectors used at the LCLS, but also is emitted on the subpicosecond timescale of electron recirculation. This is faster than even the 5 ps gate time achieved using pulse-dilating fast x-ray framing cameras on the National Ignition Facility [37][38][39][40]. Temporal gating is expected to result in only a marginal improvement in signal discrimination.…”

X-ray framing imaging technique applied in laser fusion

“…深圳大学于2016年研制了 时间分辨率为75 ps的单分幅超快CMOS图像传感器 [59] . 35 μm [51,60] . 以hCMOS作为探测器件的新型门控X射线 分幅相机, 在国外已经应用于ICF成像, 如SLOS-CBI已 安装于NIF, SLOS-TRXI已安装于OMEGA, 未来将朝着 更多画幅数、更高时间分辨率和更大动态范围等方向 发展 [40,51,56,59,61] .…”