An x-ray penumbral imager for measurements of electron-temperature profiles in inertial confinement fusion implosions at OMEGA

Rev Sci Instrum. 2021 Apr 1;92(4):043548. doi: 10.1063/5.0041038.

Abstract

Hot-spot shape and electron temperature (Te) are key performance metrics used to assess the efficiency of converting shell kinetic energy into hot-spot thermal energy in inertial confinement fusion implosions. X-ray penumbral imaging offers a means to diagnose hot-spot shape and Te, where the latter can be used as a surrogate measure of the ion temperature (Ti) in sufficiently equilibrated hot spots. We have implemented a new x-ray penumbral imager on OMEGA. We demonstrate minimal line-of-sight variations in the inferred Te for a set of implosions. Furthermore, we demonstrate spatially resolved Te measurements with an average uncertainty of 10% with 6 μm spatial resolution.