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Title	247: Develop low-torque, high normalized fusion performance QH-mode for FNSF-AT scenario
Name:	Andrea Garofalo garofalo@fusion.gat.com	Affiliation:	General Atomics
Research Area:	Inductive Scenarios	Presentation time:	Not requested
Co-Author(s):	--	ITPA Joint Experiment :	No
Description:	Demonstrate QH-mode operation at high values of beta and betaN, and with reactor relevant values of the NBI net torque (i.e. near zero). We plan to use the magnetic counter-Ip torque from C-coil fields to produce the edge rotation shear required for QH-mode, and the off-axis current drive from a BT ramp and tilted NBI to produce and sustain a broad current profile favorable for MHD stability at low q95.	ITER IO Urgent Research Task :	No
Experimental Approach/Plan:	The plan is to further improve on the Nov. 2011 experiments [D3DMP No.: 2012-31-01] by exploring higher betan, and zero-net NBI torque.
Background:	Experiments in Nov. 2011 have shown QH-mode plasmas with low net NBI torque (<1Nm counter-Ip) and normalized fusion performance reaching G=0.4, that is the target needed for Q=10 in ITER. This result was obtained using: a Bt ramp down simultaneous to the Ip ramp up to reach q95~3.4, a large n=3 field from the C-coil to apply the counter-Ip torque necessary for QH-mode operation, co+counter NBI to increase betaN at low torque after Ip and Bt flattop. Further scenario improvements (in duration and performance) were foiled by hardware issue and limited run time. Attempts to follow up on these experiments in June 2012 did not succeed because of poor wall conditions, possibly because following a boronization which had problems with the pumping system.
Resource Requirements:	n order to maximize the NBCD from the tilted beamline, forward IP with reversed BT will be used. We will use the I/C-coil configuration with the C-coil connected to the D1 supply for up to 7 kA n=3 operation, and the I-coil connected to C-supplies for up to ~6.5 kA for n=1 correction plus n=3 operation. To optimize the error field correction, we will use 120 deg. quartet (even parity).
Diagnostic Requirements:	--
Analysis Requirements:	--
Other Requirements:	--