A multi-frame soft x-ray pinhole imaging diagnostic for single-shot applications

Area of Science:

• Plasma physics
• Fusion energy research
• X-ray imaging diagnostics

Background:

• High energy density physics experiments require detailed plasma dynamics and symmetry information.
• Existing diagnostic hardware is often destroyed during implosion phases in magnetized target fusion.
• Field Reversed Configuration (FRC) plasmas are key to fusion energy research.

Purpose of the Study:

• To design and implement a robust in-vacuum diagnostic system for capturing multi-frame soft x-ray images of FRC plasmas during compression.
• To overcome the challenge of hardware destruction in high-energy implosion experiments.
• To provide critical data for understanding plasma behavior in fusion devices.

Main Methods:

• Designed a simple in-vacuum pinhole nosecone attachment for Conflat windows.
• Coated the attachment with P-47 phosphor (3.2 mg/cm²) and a 50-nm aluminum reflective overcoat.
• Lens-coupled the system to a multi-frame Hadland Ultra intensified digital camera.
• Compared visible and soft x-ray axial images of translating plasmas.

Main Results:

• Successfully obtained multi-frame soft x-ray images of FRC plasmas during compression.
• The diagnostic system proved resilient to the harsh experimental environment.
• Acquired valuable dynamics and symmetry information from the plasma implosion.
• Enabled comparison of imaging data between FRX-L and FRCHX machines.

Conclusions:

• The developed in-vacuum diagnostic system is effective for imaging FRC plasmas in high energy density fusion experiments.
• This method provides a viable solution for obtaining diagnostic data without hardware destruction.
• The obtained images offer crucial insights into plasma dynamics and symmetry, advancing fusion energy research.