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Lower Hybrid Current Drive in Tore Supra and Jet (1991) |
- Moreau, D.,
- Gormezano, C.,
- Agarici, G.,
- Agostini, E.,
- Ane, J. M.,
- Auge, N.,
- Balme, S.,
- Basiuk, V.,
- Bareyt, B.,
- Bayetti, P.,
- Beaumont, B.,
- Becherer, R.,
- Becoulet, A.,
- Benkadda, M.,
- Bergerby, G.,
- Bessette, D.,
- Bibet, P.,
- Bizarro, J. P.,
- Bonmardion, G.,
- Bonnel, P.,
- Bottereau, J. M.,
- Bottiglioni, F.,
- Brugnetti, R.,
- Bruneau, J. L.,
- Buravand, Y.,
- Capes, H.,
- Capitain, J. J.,
- Chappuis, P.,
- Chatain, D.,
- Chatelier, A.,
- Chatelier, M.,
- Ciazynski, D.,
- Cordier, J. J.,
- Coston, J. F.,
- Coulon, J. P.,
- Couturier, B.,
- Crenn, J. P.,
- Deck, C.,
- Degentile, B.,
- Demarthe, H.,
- Demichelis, C.,
- Deschamps, P.,
- Devynck, P.,
- Doceul, L.,
- Dougnac, M.,
- Drawin, H. W.,
- Dubois, M.,
- Duchateau, J. L.,
- Dupas, L.,
- Edery, D.,
- Elbeze, D.,
- Evans, T.,
- Fall, T.,
- Farjon, J. L.,
- Fidone, I.,
- Fois, M.,
- Foster, C. A.,
- Fumelli, M.,
- Gagey, B.,
- Garbet, X.,
- Gauthier, E.,
- Geraud, A.,
- Gervais, F.,
- Gendrih, P.,
- Gil, C.,
- Giruzzi, G.,
- Goniche, M.,
- Gravier, R.,
- Gravil, B.,
- Gregoire, M.,
- Gresillon, D.,
- Grisolia, C.,
- Grosman, A.,
- Guilhem, D.,
- Guillerminet, B.,
- Hennequin, P.,
- Hennion, F.,
- Hertout, P.,
- Hess, W. R.,
- Hesse, M.,
- Hoang, G. T.,
- Horton, L.,
- Hubbard, A.,
- Hutter, T.,
- Idmtal, J.,
- Jacquot, C.,
- Jager, B.,
- Javon, C.,
- Jequier, F.,
- Joffrin, E.,
- Johner, J.,
- Journeaux, J. Y.,
- Joyer, P.,
- Kuus, H.,
- Lafon, D.,
- Lasalle, J.,
- Laurent, L.,
- Laviron, C.,
- Leclert, G.,
- Lecoustey, P.,
- Leloup, C.,
- Libeyre, P.,
- Lipa, M.,
- Litaudon, X.,
- Loarer, T.,
- Lotte, P.,
- Magaud, P.,
- Magne, R.,
- Martin, G.,
- Martinez, A.,
- Maschke, E. K.,
- Mattioli, M.,
- Mayaux, G.,
- Mioduszewski, P.,
- Misguich, J.,
- Moniergarbet, P.,
- Moreau, D.,
- Morera, J. P.,
- Moret, J. M.,
- Moulin, B.,
- Moulin, D.,
- Mourguesmillot, F.,
- Moustier, M.,
- Nguyen, F.,
- Olivain, J.,
- Ouvrierbuffet, P.,
- Pamela, J.,
- Panzarella, A.,
- Parlange, F.,
- Pastor, G.,
- Patris, R.,
- Paume, M.,
- Pecquet, A. L.,
- Pegourie, B.,
- Peysson, Y.,
- Piat, D.,
- Picchiottino, J. M.,
- Pierre, J.,
- Platz, P.,
- Portafaix, C.,
- Poutchy, F.,
- Prou, M.,
- Quemeneur, A.,
- Rax, J. M.,
- Rey, G.,
- Riband, P.,
- Rigaud, D.,
- Rodriguez, L.,
- Rothan, B.,
- Roubin, J. P.,
- Roussel, P.,
- Saha, S. K.,
- Samaille, F.,
- Samain, A.,
- Saoutic, B.,
- Schlosser, J.,
- Seigneur, A.,
- Segui, J. L.,
- Shepard, T.,
- Soler, K.,
- Stirling, W.,
- Tachon, J.,
- Talvard, M.,
- Tonon, G.,
- Torossian, A.,
- Truc, A.,
- Turck, B.,
- Uckan, T.,
- Vallet, J. C.,
- Vanhoutte, D.,
- Weisse, J.,
- Zou, X. L.
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Abstract |
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Recent Lower Hybrid Current Drive (LHCD) experiments in TORE SUPRA and JET are reported. Large multijunction launchers have allowed the coupling of 5 MW to the plasma for several seconds with a maximum of 3.8 kw/cm2. Measurements of the scattering matrices of the antennae show good agreement with theory. The current drive efficiency in TORE SUPRA is about 0.2 x 10(20) Am-2/W with LH power alone and reaches 0.4 x 10(20) Am-2/W in JET thanks to a high volume-averaged electron temperature (1.9 keV) and also to a synergy between Lower Hybrid and Fast Magnetosonic Waves. At N(e)BAR = 1.5 x 10(19) m-3 in TORE SUPRA, sawteeth are suppressed and m = 1 MHD oscillations the frequency of which clearly depends on the amount of LH power are observed on soft x-rays, and also on non-thermal ECE. In JET ICRH produced sawtooth-free periods are extended by the application of LHCD (2.9 s. with 4 MW ICRH) and current profile broadening has been clearly observed consistent with off-axis fast electron populations. LH power modulation experiments performed in TORE SUPRA at N(e)BAR = 4 x 10(19) m-3 show a delayed central electron heating despite the off-axis creation of suprathermal electrons, thus ruling out the possibility of a direct heating through central wave absorption. A possible explanation in terms of anomlous fast electron transport and classical slowing down would yield a diffusion coefficient of the order of 10 m2/s for the fast electrons. Other interpretations such as an anomalous heat pinch or a central confinement enhancement cannot be excluded. Finally, successful pellet fuelling of a partially LH driven plasma was obtained in TORE SUPRA, 28 successive pellets allowing the density to rise to N(e)BAR = 4 x 10(19) m-3. This could be achieved by switching the LH power off for 90 ms before each pellet injection, i.e. without modifying significantly the current density profile. |
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