The NIF x-ray spectrometer calibration campaign at Omega

Area of Science:

• Plasma Physics
• X-ray Spectroscopy
• Nuclear Fusion

Background:

• Accurate x-ray diagnostics are crucial for inertial confinement fusion (ICF) experiments.
• The National Ignition Facility X-ray Spectrometer (NXS) requires precise calibration for reliable data acquisition.

Purpose of the Study:

• To calibrate the National Ignition Facility X-ray Spectrometer (NXS) in the 2-18 keV energy range.
• To validate the performance of designed laser-driven x-ray sources for spectrometer calibration.
• To compare experimental measurements with radiation hydrodynamics simulations.

Main Methods:

• Conducted a calibration campaign at the Omega laser facility.
• Designed and utilized millimeter-scale, spherically symmetric, laser-driven x-ray sources emitting K-shell and L-shell radiation from mid-Z elements.
• Measured absolute spectral brightness using two calibrated spectrometers.
• Employed radiation hydrodynamics simulations to model source performance.

Main Results:

• Successfully calibrated the NXS across the 2-18 keV energy spectrum.
• Achieved good agreement between measured spectral brightness and predictions from radiation hydrodynamics simulations.
• Demonstrated the effectiveness of the designed laser-driven x-ray sources for NXS calibration.

Conclusions:

• The calibration campaign successfully validated the performance of the NXS.
• Radiation hydrodynamics simulations accurately predicted the behavior of the laser-driven x-ray sources.
• The NXS is ready for deployment and accurate measurements in future ICF experiments.