DIII-D RESEARCH OPPORTUNITIES FORUM FOR THE 2013 EXPERIMENTAL CAMPAIGN Review | Direct submission with log-in | Request submission without log-in
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Title	3: The effect of LSN Shape on the q95 windows in RMP ELM Suppression
Name:	John deGrassie degrassie@fusion.gat.com	Affiliation:	General Atomics
Research Area:	ELM Control	Presentation time:	Not requested
Co-Author(s):		ITPA Joint Experiment :	No
Description:	The purpose of this experiment is to understand what selects the q95 windows that work for RMP ELM suppression (n=3) by using systematic shape changes in LSN discharges.	ITER IO Urgent Research Task :	Yes
Experimental Approach/Plan:	Start with a standard LSN (ITER-like) shape with standard RMP suppression (q95 ~ 3.5, double I-coil row n=3) and vary the shape while measuring the q95 window of suppression. Vary triangularities, and squareness values. Use Ip ramps.
Background:	We know that shape modifies the q95 windows in LSN discharges ( see Schmitz et al, NF 52, 043005 (2012) ), from these experiments done on two distinct LSN shapes. But no systematic experiments have been done to map out the q95 regions with continuous shape variations to understand the trade-offs between the local resonance (outboard field line pitch) and the global resonance (q95 value).
Resource Requirements:	1 day experiment 2 days if compelling results obtained. Standard DIII-D RMP experiment, operational hardware and diagnostics. Consider the trade-offs between using lower BT (more I-coil current headroom), diagnostic coverage, and possible use of ECH.
Diagnostic Requirements:
Analysis Requirements:
Other Requirements: