(EXP5/13) Energy Confinement and Sawtooth Stabilization by ECRH at High
Electron Density in FTU Tokamak
C. Sozzi1), S. Cirant1),
A. Airoldi1), G. Bracco2), A. Bruschi1),
P. Buratti2), F. Gandini1),
G. Granucci1), A. Jacchia1),
H. Kroegler2), E. Lazzaro1), S. Nowak1),
G. Ramponi1), O. Tudisco2),
B. Angelini2), M. L. Apicella2),
G. Apruzzese2), E. Barbato2),
L. Bertalot2), A. Bertocchi2),
G. Buceti2), A. Cardinali2),
C. Centioli2), R. Cesario2),
S. Ciattaglia2), V. Cocilovo2),
F. Crisanti2), R. De Angelis2),
M. De Benedetti2), B. Esposito2),
D. Frigione2), L. Gabellieri2),
G. Gatti2), E. Giovannozzi2),
C. Gormezano2), M. Grolli2),
M. Leigheb2), G. Maddaluno2),
M. Marinucci2), G. Mazzitelli2),
P. Micozzi2), F. P. Orsitto2),
D. Pacella2), L. Panaccione2),
M. Panella2), V. Pericoli-Ridolfini2),
L. Pieroni2), S. Podda2), G. Pucella2),
G. B. Righetti2), F. Romanelli2),
S. E. Segre3), A. Simonetto1),
P. Smeulders2), E. Sternini2),
N. Tartoni2), A. A. Tuccillo2),
V. Vitale2), G. Vlad2), V. Zanza2),
M. Zerbini2), F. Zonca2)
1) Associazione EURATOM-ENEA-CNR, Istituto di Fisica
del Plasma, Milano, Italy
2) Associazione EURATOM-ENEA sulla Fusione, C.R. Frascati, Frascati,
Roma, Italy
3) INFM and Università di Roma ``Tor Vergata'', Roma, Italy
Abstract. The dependence of the local effective electron thermal
diffusivity and of the global energy confinement on the intensity and the
distribution of the heat source is explored in ECRH experiments performed on
FTU tokamak. Energy transport is analysed by applying a dominant EC heating
with
Pecrh 0.8MW and
Poh 0.2MW during ECRH,
at the frequency of 140 GHz correspondent to the fundamental electron
cyclotron resonance at
Btor = 5T. In order to discriminate the
underlying diffusive transport against internal disruptions events, ECRH is
also used to stabilize sawteeth. In these conditions, the predominance of
ECRH over OH allows a good estimate of heat fluxes. Ion heating in the order
of
Ti/Ti 30% is observed in experiments with central
density up to
1020m- 3.
IAEA 2001