1. Advanced Scenarios: ITER-like Hybrid at Low Bt without LH
C. Kessel
Princeton Plasma Physics Laboratory
Alcator C-Mod, Ideas Forum 2011
January 10-12, 2011

2. Hybrid type discharges
How are they accessed (IOS JE)
H-mode onset time
Value of q(0) > 1 thru rampup
Ip over current in JET
High vs low power when, AUG sees better results with late high power
Non-ideal MHD modes
Flattop plasmas
Value of βN < βNno wall (roughly )
Value of q(0) > 1 (but very close)
Profile of q(ρ) very flat from core to at least half radius (known to shut off certain drift waves)
Non-ideal MHD modes present (3/2, 4/3, fishbones), but weak effect on confinement
Value of q95 > 4 with no sawteeth

3. Based on MP574 1110104, ITER-like Low Bt
Operated at 2.7 T, so using 2nd harmonic H-minority, but have all power available
Ip = 650 kA, q95 ~ 3-3.2
Reached betaN ~ 1.7 (ave over H-mode phase) with < 3 MW
Looks like QCM at 100 kHz in H-mode phases
HYBRID: make Ip ~ 525 kA, so q95 = 4-ish
Optimize heating and raise betaN further

4. Whenever betaN > 1.4 mode appears at 10 kHz
1.5
1.5
betaN
betaN
Whenever betaN > 1.4 mode appears at 10 kHz
There is other stuff there, but this is consistent and persistent
The mode does not slow down and does not disrupt the plasma
1.5
1.5
betaN