Developing time-resolved x-ray diffraction diagnostics at the National Ignition Facility (invited)

Area of Science:

• Materials Science
• High-Energy-Density Physics
• X-ray Science

Background:

• Measuring phase transition timescales under dynamic compression is crucial for materials science.
• Existing methods face challenges in harsh experimental environments and signal-to-noise ratios.

Purpose of the Study:

• To design and develop advanced x-ray imaging diagnostics for in situ measurements of dynamic compression experiments.
• To overcome environmental challenges and improve x-ray diffraction data quality.

Main Methods:

• Development of staged diagnostics, starting with a demonstration platform (Gated Diffraction Development Diagnostic).
• Implementation of a flexible instrument (Flexible Imaging Diffraction Diagnostic for Laser Experiments) with multiple ns-gated hybrid CMOS sensors.
• Protection of sensors from debris, electromagnetic pulses, and laser light in a harsh environment.

Main Results:

• Successful protection of sensors and acquisition of acceptable diffraction data in the demonstration phase.
• Development of a more ambitious instrument capable of fielding up to eight sensors in a flexible geometry.
• Identification and progress in addressing challenges related to complexity and data quality at the National Ignition Facility (NIF).

Conclusions:

• Staged development approach effectively assessed risks and addressed challenges in designing complex x-ray diagnostics.
• The Flexible Imaging Diffraction Diagnostic for Laser Experiments offers enhanced capabilities for studying dynamic compression.
• Ongoing work focuses on reducing x-ray background and quantifying measurement uncertainties to improve data quality.