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Title: Spitzer or neoclassical resistivity: A comparison between measured and model poloidal field profiles on PBX-M

Direct measurements of the radial profile of the magnetic field line pitch on PBX-M coupled with model predictions of these profiles allow a critical comparison with the Spitzer and neoclassical models of plasma parallel resistivity. The measurements of the magnetic field line pitch are made by Motional Stark Effect polarimetry, while the model profiles are determined by solving the poloidal field diffusion equation in the TRANSP transport code using measured plasma profiles and assuming either Spitzer or neoclassical resistivity. The measured field pitch profiles were available for only seven cases, and the model profiles were distinguishable from each other in only three of those cases due to finite resistive diffusion times. The data in two of these three were best matched by the Spitzer model, especially in the inner half of the plasma. Portions of the measured pitch profiles for these two cases and the full profiles for other cases, however, departed significantly from both the Spitzer and neoclassical models, indicating a plasma resistivity profile different from either model.
Authors:
; ; ; ; ; ;  [1] ;  [2]
  1. Princeton Univ., NJ (United States). Plasma Physics Lab.
  2. Fusion Physics and Technologies, Torrance, CA (United States)
Publication Date:
OSTI Identifier:
10115620
Report Number(s):
PPPL--2807
ON: DE92006818
DOE Contract Number:
AC02-76CH03073
Resource Type:
Technical Report
Resource Relation:
Other Information: PBD: Jan 1992
Research Org:
Princeton Univ., NJ (United States). Plasma Physics Lab.
Sponsoring Org:
USDOE, Washington, DC (United States)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; COMPACT IGNITION TOKAMAK; MAGNETIC FIELDS; DIFFUSION; NEOCLASSICAL TRANSPORT THEORY; TEMPERATURE DISTRIBUTION; POLARIMETRY; PLASMA DIAGNOSTICS; ELECTRIC CONDUCTIVITY 700310; 700430; PLASMA CONFINEMENT; MAGNET COILS AND FIELDS