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<b>Gyrokinetic Calculations of the Neoclassical Radial Electric Field in Stellarator Plasmas</b>
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<b>Authors:</b> J.L.V. Lewandowski, J. Williams, A.H. Boozer, and Z. Lin</p>

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<b>Original date of PPPL Report:</b> April 2001
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<b>Published in:</b> Phys. Plasmas <b>8</b> (June 2001) 2849-2854.</p>
 
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A novel method to calculate the neoclassical radial electric field in stellarator plasmas is described. The method, which does not have the inconvenience of large statistical fluctuations (noise) of standard Monte Carlo technique, is based on the variation of the combined parallel and perpendicular pressures on a magnetic surface. Using a three-dimensional gyrokinetic <font face="symbol">d</font face="symbol"><I>f</I> code, the calculation of the radial electric field in the National Compact Stellarator Experiment has been carried out. It is shown that a direct evaluation of radial electric field based on a direct calculation of the radial particle flux is not tractable due to the considerable noise.
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