Synergy in Two-Frequency Fast Wave Cyclotron Harmonic Absorption in DIII-D

Journal Article · Thu Nov 26 04:00:00 EST 2009 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.3273841· OSTI ID:21335817

Pinsker, R I; Choi, M ^[1]; Heidbrink, W W; Zhu, Y ^[2]; Porkolab, M ^[3]; Baity, F W ^[4]; Hosea, J C ^[5]

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1. General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States)
2. University of California-Irvine, Irvine, California (United States)
3. Massachusetts Institute of Technology, Cambridge, Massachusetts (United States)
4. Oak Ridge National Laboratory, Oak Ridge, Tennessee (United States)
5. Princeton Plasma Physics Laboratory, Princeton, New Jersey (United States)

Fast waves (FWs) at 60 MHz and at 90 MHz are coupled to DIII-D discharges for central heating and current drive at net FW power up to 3.5 MW. The primary absorption mechanism is intended to be direct electron damping in the plasma core. In discharges at B = 2 T with fast deuteron populations from neutral beam injection, 4th and 6th deuterium cyclotron harmonic absorption on the fast ions competes with direct electron damping. Previous experiments have shown that the 6{omega}{sub D} absorption of the 90 MHz FWs is weaker than the 4{omega}{sub D} absorption of 60 MHz FWs, in agreement with a model that includes unspecified edge losses. Recent experiments have shown that if the fast deuterons are accelerated by absorption of 60 MHz (4{omega}{sub D}) FWs, adding 90 MHz power (6{omega}{sub D}) can increase the fusion neutron rate by a larger increment than is obtained with 90 MHz power alone. Details of this synergy between 4{omega}{sub D} and 6{omega}{sub D} absorption are presented.

• OSTI ID: 21335817
• Journal Information: AIP Conference Proceedings, Journal Name: AIP Conference Proceedings Journal Issue: 1 Vol. 1187; ISSN 0094-243X; ISSN APCPCS
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
ABSORPTION
ALFVEN WAVES
DAMPING
DEUTERIUM
DEUTERONS
DOUBLET-3 DEVICE
ELECTRIC CURRENTS
ELECTRIC DISCHARGES
ELECTRONS
IONS
MHZ RANGE
NEUTRONS
PLASMA
PLASMA CONFINEMENT
PLASMA HEATING