X-ray analysis of electron Bernstein wave heating in MST

Area of Science:

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

Background:

• Electron Bernstein wave heating is a key technique for heating plasma in fusion devices.
• Understanding electron behavior is crucial for achieving controlled fusion.
• Reversed Field Pinch (RFP) devices offer unique plasma confinement properties.

Purpose of the Study:

• To develop and implement a pulse height analyzing X-ray tomography system.
• To detect and analyze X-rays emitted by electron Bernstein wave heated electrons.
• To investigate electron spectrum, transport, and diffusion in RFP plasmas.

Main Methods:

• Utilized a pulse height analyzing X-ray tomography system with cadmium zinc telluride detectors.
• Employed a parallel beam array with orthogonal multi-chord detectors for tomography.
• Used a repositionable 16-channel fan beam camera to augment data.
• Analyzed chord-integrated signals of X-ray emission from electrons striking a limiter.

Main Results:

• Successfully detected X-rays from electron Bernstein wave heated electrons in the Madison Symmetric Torus RFP.
• Observed RF-induced X-ray emission from absorption on harmonic electron cyclotron resonances.
• Gathered data on heated electron spectrum, transport, and diffusion.

Conclusions:

• The developed X-ray tomography system is effective for diagnosing heated electrons in RFP plasmas.
• RF-induced X-ray emission provides valuable information about electron-resonant interactions.
• The findings contribute to understanding plasma heating and transport mechanisms in fusion devices.