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Title	323: Access to QH-mode with low NBI torque
Name:	Wayne Solomon solomon@fusion.gat.com	Affiliation:	General Atomics
Research Area:	Inductive Scenarios	Presentation time:	Not requested
Co-Author(s):	KH Burrell, AM. Garofalo	ITPA Joint Experiment :	No
Description:	The aim of this experiment is to determine the torque and rotation requirements for access to QH-mode.	ITER IO Urgent Research Task :	No
Experimental Approach/Plan:	This is an addendum to ROF #53, and would utilize work performed in ROF #118 and #322. One would start with a low torque ITER baseline discharge and add NRMF before the L-H transition to try to drive sufficient rotation shear to enter QH-mode directly, ideally with no ELMs. If the early NRMF is deemed undesirable (eg increase L-H power threshold), then delay the NRMF until after the L-H transition, and use pellet pacing to mitigate the early ELMs until a transition to QH-mode is achieved. If QH-mode is not achieved in this way, go to maximum counter NBI for the startup and then work back toward ITER relevant torque.
Background:	The torque from NRMFs have been successfully used to enable operation of QH-mode at low torque. However, to date, these fields have only been applied after the high rotation shear conditions needed for QH-mode have been established with neutral beam torque. Since the torque from the NRMF shows a significant beta dependence, it is not known whether the torque will be adequate to allow a direct transition from L-mode to QH-mode. In addition, the possible impact of NRMFs on the H-mode power threshold has not been documented for low collisionality QH-mode conditions.
Resource Requirements:	1 day expt, 6 gyrotorons, 210 beams, pellets, n=3 NRMF
Diagnostic Requirements:
Analysis Requirements:
Other Requirements: