Sample interview questions: Can you discuss your knowledge of plasma equilibrium reconstruction algorithms for field-reversed configurations?
Sample answer:
Plasma equilibrium reconstruction algorithms for field-reversed configurations (FRCs) play a crucial role in understanding and controlling these unique fusion devices. Here are key aspects of these algorithms:
Reconstruction Techniques:
- Magnetic Diagnostics: Measure magnetic field components using arrays of magnetic probes and reconstruct the plasma shape using inverse methods (e.g., Grad-Shafranov, Bayesian methods).
- Thomson Scattering: Infer plasma density and temperature profiles from the scattering of laser light, providing a direct measurement of the plasma equilibrium.
- Fast Camera Imaging: Use high-speed cameras to capture the FRC’s visible light emission, providing information about the plasma boundary and dynamics.
Specific Algorithms:
- Grad-Shafranov Reconstruction: Solves a set of differential equations derived from MHD equilibrium to find the plasma’s magnetic field and current distribution.
- Bayesian Reconstruction: Uses Bayesian statistics to infer the plasma equilibrium from measured magnetic field data, taking into account uncertainties and model assumptions. Read full answer