Talbot-Lau x-ray deflectometer: Refraction-based HEDP imaging diagnostic.

Area of Science:

• Plasma Physics
• X-ray Optics
• High Energy Density Physics (HEDP)

Background:

• Talbot-Lau x-ray interferometry is a key technique for diagnosing electron density gradients.
• High Energy Density Physics (HEDP) experiments require advanced diagnostics to probe extreme conditions.
• Previous methods had limitations in spatial resolution and contrast for dense plasma characterization.

Purpose of the Study:

• To implement and evaluate Talbot-Lau X-ray Deflectometry (TXD) for HEDP applications.
• To optimize x-ray backlighter targets and diagnostic components for TXD.
• To demonstrate TXD's capability in imaging dense plasma phenomena.

Main Methods:

• Utilized Cu foils, wires, and sphere targets irradiated by high-power laser pulses (10-150 J, 8-30 ps).
• Employed pulsed-power generators (∼350 kA, 350 ns and ∼200 kA, 150 ns) to drive various x-pinch configurations.
• Assessed x-ray CCDs, image plates, and x-ray film for backlighter optimization, spatial resolution, and interferometer contrast.

Main Results:

• Successfully imaged a plasma ablation front at densities >10^23 cm^-3 for the first time using TXD.
• Evaluated different backlighter targets and detection methods to enhance spatial resolution and interferometer contrast.
• Characterized plasma conditions in both pulsed-power and high-intensity laser environments.

Conclusions:

• Talbot-Lau X-ray Deflectometry (TXD) proves to be a powerful and versatile diagnostic tool for HEDP.
• TXD enables accurate characterization of electron density gradients in dense plasmas.
• The optimized TXD system shows significant potential for future HEDP research.