Open AccessEffects of Finite Density Fluctuations and of the Upper Hybrid Resonance on O-X Correlation Reflectometry
Author(s) -
G. J. Kramer,
R. Nazikian,
E. Valeo
Publication year - 2001
Language(s) - English
Resource type - Reports
DOI - 10.2172/775581
Subject(s) - extrapolation , resonance (particle physics) , magnetic field , reflectometry , mode (computer interface) , correlation , physics , core (optical fiber) , scale (ratio) , computational physics , condensed matter physics , atomic physics , optics , mathematics , geometry , mathematical analysis , quantum mechanics , time domain , computer science , computer vision , operating system
The correlation between O-mode and X-mode reflectometer signals is studied with a 1-D reflectometer model taking into account the influence of finite density fluctuation levels and the upper hybrid resonance. It is found that a high level of O-X correlation can only be achieved for sufficiently small density fluctuation levels (typically much less than 1%) or very low magnetic field strengths. The influence of the upper hybrid resonance on the O-X correlation was found to also degrade the correlation between the O and X mode signals for very low magnetic field strengths or for very short density scale lengths. The extrapolation of these results to reactor-scale parameters indicates that the magnetic field strength can reliably be measured in the core plasma provided the density fluctuation level is typically much less than 1%