PPPL-3739rev is available in <a href="PPPL-3739rev.pdf">pdf</a> format (652 KB).

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<b>Localized Measurement of Turbulent Fluctuations in Tokamaks with Coherent Scattering
of Electromagnetic Waves</b>
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<b>Author:</b> E. Mazzucato
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<b>Date of PPPL Report:</b> August 2002<BR><br>
<b>Date of Revised PPPL Report:</b> December 2002
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<b>Published in:</b> Physics of Plasmas <b>10</b> No. 3 (March 2003) 753 - 759
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Localized measurements of short-scale turbulent fluctuations in tokamaks are still an outstanding problem. In this paper, the method of coherent scattering of electromagnetic waves for the detection of density fluctuations is revisited. Results indicate that the proper choice of frequency, size and launching of the probing wave can transform this method into an excellent technique for high-resolution measurements of those fluctuations that plasma theory indicates as the potential cause of anomalous transport in tokamaks. The best spatial resolution can be achieved when the range of scattering angles corresponding to the spectrum of fluctuations under investigation is small. This favors the use of high frequency probing waves, such as those of far infrared lasers. The application to existing large tokamaks is discussed.



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