Central electron temperature enhancements due to sawtooth stabilization during counter electron cyclotron current drive in Tokamak a Configuration Variable
Za. Pietrzyk et al., Central electron temperature enhancements due to sawtooth stabilization during counter electron cyclotron current drive in Tokamak a Configuration Variable, PHYS PLASMA, 7(7), 2000, pp. 2909-2914
In the Tokamak a Configuration Variable (TCV), the central electron tempera
ture obtained in discharges with counter (CNTR) electron cyclotron current
drive (ECCD) is larger than with CO-ECCD or electron cyclotron resonance he
ating (ECRH) alone. Comparison of experimental results with calculations by
the transport code PRETOR [IAEA Technical Conference on Advances in Simula
tion and Models of Thermonuclear Plasmas. Montreal 142 (International Atomi
c Energy Agency, Vienna 1992)] indicates that sawtooth stabilization is res
ponsible for the increased confinement time and the attendant twofold enhan
cement of the central temperature. Sawtooth stabilization is caused in turn
by the central safety factor q(0) rising above 1 for CNTR-ECCD; by contras
t, the simulation results show that q(0)< 1 in the sawtoothing CO-ECCD and
ECRH cases. (C) 2000 American Institute of Physics. [S1070-664X(00)03907-0]
.