Novel energy resolving x-ray pinhole camera on Alcator C-Mod.

Area of Science:

• Plasma Physics
• Fusion Energy Research
• X-ray Diagnostics

Background:

• Alcator C-Mod tokamak requires advanced diagnostics for plasma characterization.
• Existing x-ray imaging systems have limitations in energy and spatial resolution.

Purpose of the Study:

• To introduce and characterize a new energy-resolving x-ray pinhole camera for Alcator C-Mod.
• To demonstrate the capabilities of a novel detector calibration technique.

Main Methods:

• Installation of an energy-resolving x-ray pinhole camera with a Pilatus 2 hybrid-pixel detector.
• Adjustment of individual pixel energy thresholds for multi-energy range sensitivity.
• Calibration of the detector to characterize energy resolution.

Main Results:

• The diagnostic achieves spatial resolution of ≈1 cm and energy resolution of ≈1 keV (3.5-15 keV range).
• Maximum temporal resolution of 5 ms is achieved.
• Initial data demonstrates effective impurity emission measurement.

Conclusions:

• The new x-ray pinhole camera enhances plasma diagnostics on Alcator C-Mod.
• The developed detector calibration technique enables multi-energy sensitivity within a single detector.
• This diagnostic is valuable for determining impurity concentrations and electron energy distribution.