1. RF Heating and CD at low frequencies (below all ion cyclotron harmonic resonances)
C.K. Phillips, J. Hosea, E. Valeo, J.R. Wilson
PPPL
P. Bonoli, Y. Lin, R. Parker, M. Porkolab, J. Wright and S. Wukitch
PSFC-MIT
C-Mod 2007 Ideas Forum

2. Overview
GOAL:
-Explore RF heating and current drive in the low frequency regime by launching fast waves with f ≤ fci for all ions
PURPOSE:
-potential applications in ITER / reactors
-unique C-Mod capability: high BT and low RF frequency
APPROACH:
-launch fast waves at 40 MHz into D plasma with BT > 7T
-use power modulation / power notch to measure absorption profile
-possibly preheat with lower hybrid to improve electron damping
-possibly detect shear Alfven wave with PCI
- half a day run required?
C-Mod 2007 Ideas Forum

3. With 40 MHz and BT > 7T, almost all possible ion resonances are out of the machine
LFS edge of plasma
C-Mod 2007 Ideas Forum

4. Simulations indicate that Alfvén Wave heating regime is accessible on C-Mod at 8T with 40 MHz
TORIC mock-up of low frequency regime:
Use H minority test case at 5.3T but lower frequency to 25 MHz
coherent mode is probably kinetic shear Alfvén wave
qualitatively consistent with earlier 1D studies with METS at 8T, 40 MHz
mode damps on electrons
Possibly detectable with PCI?
C-Mod 2007 Ideas Forum

5. C-Mod 2007 Ideas Forum