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Title: Implementing Faraday effect measurement constraints into the Grad–Shafranov equilibrium fitting code EFIT

Journal Article · · Review of Scientific Instruments
DOI:https://doi.org/10.1063/5.0129892· OSTI ID:1971107

A new tool for the exploration and diagnosis of the internal magnetic field of plasmas in the DIII-D tokamak in the form of a constraint on the EFIT (Equilibrium Fitting) Grad–Shafranov code based on the Faraday-effect Radial Interferometer-Polarimeter (RIP) diagnostic is presented, including description, verification, and sample application. The physics underlying the diagnostic and its implementation into EFIT are discussed, and the results showing the verification of the model are given, and the model’s limitations are discussed. The influence of the diagnostic’s input on the resulting equilibrium parameters is characterized. Furthermore, the effect of electron density profile refinement is evaluated and found to be negligible. A sample application of the diagnostic is shown, indicating that the RIP constraint has similar effects on the equilibrium as motional Stark effect constraints do.

Research Organization:
Univ. of California, Los Angeles, CA (United States); General Atomics, San Diego, CA (United States)
Sponsoring Organization:
USDOE
Grant/Contract Number:
SC0019004; FC02-04ER54698
OSTI ID:
1971107
Alternate ID(s):
OSTI ID: 1909044
Journal Information:
Review of Scientific Instruments, Vol. 94, Issue 1; ISSN 0034-6748
Publisher:
American Institute of Physics (AIP)Copyright Statement
Country of Publication:
United States
Language:
English

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