(PD/2) Full Absorption of 3rd Harmonic ECH in TCV Target Plasmas Produced
by 2nd Harmonic ECH and ECCD
S. Alberti1), T. Goodman1),
M. A. Henderson1), A. Manini1),
J.-M. Moret1), P. Gomez1),
P. Blanchard1), S. Coda1), O. Sauter1),
C. Angioni1), K. Appert1), R. Behn1),
P. Bosshard1), R. Chavan1),
I. Condrea1), A. Degeling1),
B. P. Duval1), D. Fasel1),
J.-Y. Favez1), I. Furno1), F. Hofmann1),
P. Lavanchy1), J. B. Lister1),
X. Llobet1), Z. A. Pietrzyk1),
A. Gorgerat1), P. Gorgerat1),
J.-P. Hogge1), P.-F. Isoz1), B. Joye1),
J.-C. Magnin1), B. Marlétaz1),
P. Marmillod1), Y. R. Martin1),
A. Martynov1), J.-M. Mayor1),
J. Mlynar1), P. Nikkola1),
P. J. Paris1), A. Perez1), Y. Peysson2),
R. A. Pitts1), A. Pochelon1),
H. Reimerdes1), J. H. Rommers1),
E. Scavino1), G. Tonetti1),
M. Q. Tran1) and H. Weisen1)
1) Centre de Recherches en Physique des Plasmas,
Association EURATOM-Confédération Suisse, Ecole Polytechnique Fédérale de
Lausanne, CH-1015 Lausanne, Switzerland
2) Association Euratom-CEA sur la Fusion, DRFC, CEA-Cadarache, France
Abstract. An experimental study of the extraordinary mode (X-mode)
absorption at the third cyclotron harmonic frequency (118GHz) has been
performed on the TCV Tokamak in plasmas preheated by X-mode at the second
harmonic (82.7GHz). Various preheating configurations have been
experimentally investigated, ranging from counter-ECCD, ECH to CO-ECCD at
various power levels. Full absorption of the 470kW of injected X3 power was
measured with as little as 350kW of X2-CO-ECCD preheating. The measured
absorption exceeds that predicted by the linear ray tracing code TORAY by
more than a factor of 2 for the CO-ECCD case. Experimental evidence
indicates that a large fraction of the X3 power is absorbed by electrons in
an energetic tail created by the X2-ECCD preheating.
IAEA 2001