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Title	116: Influence of non-axisymmetric fields (TBMs / RMPs) on fast ion confinement and loss
Name:	Alberto Loarte-Prieto Alberto.Loarte@iter.org	Affiliation:	ITER Organization
Research Area:	Energetic Particles	Presentation time:	Requested
Co-Author(s):	S Pinches, WW Heidbrink, GJ Kramer, MA Van Zeeland, M García-Muñoz, X Chen	ITPA Joint Experiment :	Yes
Description:	The aim is to establish the expected fast ion losses in the ITER baseline scenario arising from the non-axisymmetric field configuration present.	ITER IO Urgent Research Task :	Yes
Experimental Approach/Plan:	Use a low-current (0.6 MA), low-field standard H-mode configuration and slowly ramp the currents in the TBM mock-up coil and in the I-coils and C-coils to mimic those appropriate for ELM control in ITER. Use all available diagnostics to measure the changes in the fast ion distribution and losses. By using a plasma current of 0.6 MA, the orbit width of 75 keV beam ions in DIII-D is approximately 70% of that of alpha particles in ITER and the beam ions become a reasonable proxy for the behaviour of fusion born alpha particles. For fields lower than 1.4 T the beam ions may also be sufficiently fast compared to the Alfvén velocity to destabilise TAE modes and the combined influence of all toroidal asymmetries may be studied.
Background:	The plasma configuration in the ITER baseline scenario will not be axisymmetric: One of the ELM control strategies foreseen for ITER is the application of non-axisymmetric magnetic fields using so-called ELM control coils, whilst the presence of ferritic material in the TBMs will further destroy the axisymmetry of the plasma configuration. A consequence of breaking the toroidal symmetry, is that canonical angular momentum will not be conserved and particle drift orbits move radially leading to a degradation of fast particle confinement and increased losses. The exact details are sensitive to the configuration (plasma current and field) and so it is proposed to use an ITER-like baseline H-mode scenario to undertake measurements of the fast ion losses arising from the use of RMP coils for ELM suppression and the mocked-up TBM. If it is additionally possible to destabilise Alfvén Eigenmodes in this scenario then further information can be gained regarding all the non-axisymmetric fields considered responsible for the transport and loss of alpha particles in ITER.
Resource Requirements:	NBI system, TBM mock-up, I-coils and C-coils
Diagnostic Requirements:	Fast ion diagnostics (FIDA, FILD, NPA, neutrons), instability diagnostics (magnetics, SXR, ECEI), equilibrium diagnostics (core profiles including MSE)
Analysis Requirements:	Data provision to ITPA EP TG for modelling by fast ion codes that can treat plasma asymmetries.
Other Requirements: