Testing the optical components for the National Ignition Facility time-resolved soft x-ray opacity spectrometer...

Area of Science:

• Plasma physics
• X-ray spectroscopy
• Materials science under extreme conditions

Background:

• Opacity measurements are crucial for understanding high-energy-density physics.
• Current methods at the National Ignition Facility (NIF) are time-integrated.
• Development of time-resolved diagnostics is needed for dynamic opacity studies.

Purpose of the Study:

• To present the first tests of optics for the time-resolved opacity spectrometer (OpSpecTR).
• To evaluate a redesigned crystal geometry and a grazing angle x-ray mirror.
• To demonstrate the spectral coverage and performance of the OpSpecTR system.

Main Methods:

• Testing of an elliptical crystal and a grazing angle x-ray mirror using a Manson x-ray source.
• Characterization of mirror reflection size and reflectivity.
• Evaluation of spectral coverage with the integrated optical components.

Main Results:

• The redesigned elliptical crystal and x-ray mirror were successfully tested.
• The x-ray mirror functions as a low-pass energy filter, reducing higher energy x-ray contributions.
• The coupled optics demonstrate the intended spectral coverage for OpSpecTR.

Conclusions:

• The tested optics are suitable for the OpSpecTR system.
• The integration of the mirror and crystal enables time-resolved opacity measurements.
• This work paves the way for dynamic opacity studies at NIF.