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Title	127: Intrinsic rotation vs NTV
Name:	John Degrassie ()	Affiliation:	General Atomics
Research Area:	Rotation Physics	Presentation time:	Not requested
Co-Author(s):	A. Garofalo, G. Jackson, W. Solomon, A. Cole, J. Callen, and C. Hegna
Description:	Study the interplay of intrinsic rotation and NTV-induced rotation from n=3 I-coil error fields.
Experimental Approach/Plan:	*Do an experiment to follow the temporal transition between intrinsic rotation in ELMing ECH H-modes (co-directed) and the toroidal rotation driven by I-coil n=3 Neoclassical Toroidal Viscosity (NTV) (counter-directed). The counter-Ip n=3 NTV rotation has apparently been observed in DIII-D (Garofalo, Jackson). *Try very short NBI blips ( ~ < 4 msec ), or balanced blips ( ~ 5msec of 30L,33L,21R,21L ) to obtain a temporal record of the (slow) toroidal velocity evolution as the n=3 perturbation is turned on, and off etc. *Use small amounts of added co/counter NBI to vary the target toroidal velocity from about twice the NTV counter value to twice the intrinsic co value and follow the temporal evolution of velocity with n=3 switched on and off.
Background:	Close scrutiny of past data indicates that n=3 NTV-induced toroidal rotation (counter directed) has been observed in DIII-D (Garofalo, Jackson). To draw this conclusion one must apparently postulate that the intrinsic rotation has been quenched, or possibly reduced, by the n=3 error field. This conclusion has some uncertainty because carbon and not the main ion are measured. We believe that these experimental scans will reveal what is going on.
Resource Requirements:	standard for intrinsic rotation standard for n=3 braking experiments ECH, Beams
Diagnostic Requirements:	--
Analysis Requirements:	--
Other Requirements:	--