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Title	88: Plasma rotation with Icoil rotating fields
Name:	Gary Jackson ()	Affiliation:	General Atomics
Research Area:	Rotation Physics	Presentation time:	Not requested
Co-Author(s):	F. Volpe
Description:	Use rotating magnetic field perturbations (up to 1kHz) to increase toroidal plasma rotation in low NB torque discharges
Experimental Approach/Plan:	Using a low NB torque high BetaN discharge with n=1 TM, apply a rotating n=1 field from the Icoils. Vary frequency from 0.2 to 1kHz and observe changes in rotation using CER. Repeat with a low betaN, low torque discharge with no TM
Background:	In principle a torque can be applied to a plasma using a rotating magnetic field, analagous to an induction motor. This has been discussed by Garofalo, et. al as the induction motor model. This concept was first applied by Jackson in 2003, but the large neutral beam torque hid any possible effects from the rotating fields produced by the Icoil. More recently, Volpe has had some success by applying rotating Icoil fields to mitigate NTMs. With the advent of the DIII-D counter beams, a plasma with no applied neutral beam torque can be produced and the smaller induced Icoil torque can be evaluated. Since the islands from NTMs can drive current and produce higher torque, both high betaN plasmas (with n=1 TMs) and low betaN plasmas will be evaluated. The former discharges shouldn't be a problem to produce as they plague the RWM discharges at low rotation. Demonstration of such rotation control could be important for ITER, where methods to increase toroidal rotation for stabilization are being pursued.
Resource Requirements:	Need 0.5 run days
Diagnostic Requirements:	SXR cameras and ECE to characterize tearing modes.
Analysis Requirements:	--
Other Requirements:	--