Speakers
Description
Spectrally and temporally resolved x-ray emission of highly charged mid-Z ions is utilized for characterizing the electron temperature (Te) in the equatorial region of a laser-driven ignition-type NIF hohlraum. Line-intensity measurements are used to infer the ionization balance and electron temperature. Spectral analysis shows a peak electron temperature of Te = (2.7 ± 0.4) keV at the hohlraum equator between the high-density-carbon capsule ablator and the gold wall of the hohlraum. While we find agreement with post-shot simulations during the peak of the laser drive, some disagreement between the measured and simulated Te remains in the earlier part of the laser heating. We present a detailed error analysis of the spectroscopic measurements, the corresponding error in the electron temperature, and a discussion of the requirements for the spatial, temporal, and spectral resolution in order to constrain the radiation-hydrodynamic models currently used to simulate the plasma conditions. *This work was performed under the auspices of the U.S. Department of Energy by LLNL under Contract DE-AC52-07NA27344.
