Search

Your search keyword '"Shidara, H."' showing total 120 results
Start Over Author "Shidara, H."
120 results on '"Shidara, H."'

3. Conceptual design of the ECH upper launcher system for ITER

Author

Heidinger, R., Bertizzolo, R., Bruschi, A., Chavan, R., Cirant, S., Collazos, A., de Baar, M., Elzendoorn, B., Farina, D., Fischer, U., Gafert, J., Gandini, F., Gantenbein, G., Goede, A., Goodman, T., Hailfinger, G., Henderson, M., Kasparek, W., Kleefeldt, K., Landis, J.-D., Meier, A., Moro, A., Platania, P., Poli, E., Ramponi, G., Saibene, G., Sanchez, F., Sauter, O., Scherer, T., Serikov, A., Shidara, H., Sozzi, C., Spaeh, P., Strauss, D., Udintsev, V.S., Vaccaro, A., Zohm, H., and Zucca, C.

Published
2009
Full Text
View/download PDF

6. Edge fluctuation studies in Heliotron J

Author

Mizuuchi, T., Chechkin, V.V., Ohashi, K., Sorokovoy, E.L., Chechkin, A.V., Gonchar, V.Yu., Takahashi, K., Kobayashi, S., Nagasaki, K., Okada, H., Yamamoto, S., Sano, F., Kondo, K., Nishino, N., Kawazome, H., Shidara, H., Kaneko, S., Fukagawa, Y., Morita, Y., Nakazawa, S., Nishio, S., Tsuboi, S., and Yamada, M.

Published
2005
Full Text
View/download PDF

10. Development of the high performance Ecrh antenna for GAMMA-10

Author

Sakagoshi, Y, Imai, T, Shidara, H, Kariya, T, Minami, R, Machida, N, Nakamura, M, Harigae, M, Murofushi, N, Yamaguchi, Y, and Tatematsu, Y

Subjects
Physics::Accelerator Physics
Abstract

ECRH antenna system for central cell of GAMMA 10 was newly installed. This system was designed to improve the calculated Poynting flux reaching the resonance surface and the beam path. The power transmission efficiency has been improved from about 60 to 70 % and the beam passes the center of the resonance surface. Performance test of this system was carried out with low power and we got the performance that we expected. This system was installed to GAMMA 10 and the initial electron heating result with it has been obtained.

Published
2009

12. Front steering configuration with internal optics for the ECRH ITER Upper Launcher

Author

Moro A., Alessi E., Bruschi A., Cirant S., Chavan R., Collazos A., Farina D., Henderson M. A., Landis J. D., Platania P., Poli E., Ramponi G., Saibene G., Shidara H., Sozzi C., and Udintsev V. S.

Subjects
___
Abstract

Amongst the possible improvements in the internal optics for the ECRH Upper Launcher of ITER, which is assessed and close to com-pletion, a full quasi-optical design for the launcher has been investigated and here proposed. This option is obtained with the replacement of the mitre bends with free space mirrors and can provide improvements in terms of a reduction of the power density with respect to the mitre bends case, additional flexibility and transmission efficiency, with an overall downgrading of the costs of the launcher. In this work we present the general ideas of this proposal, starting from the present Front Steering (FS) design and following a matching approach from given final beams and positions, in order to minimize impact on design.

Published
2008

13. The ITER ECH FS launcher design for an optimized physics performance

Author

Henderson, M.A., Chavan, R., Bertizzolo, R., Campbell, D., Danilov, I., Dolizy, F., Farina, D., Kleefeldt, K., Heidinger, R., Landis, J.-D., Poli, E., Ramponi, G., Saibene, G., Sanchez, F., Sauter, O., Serikov, A., Shidara, H., Spaeh, P., and Zohm, H.

Published
2006

14. Synergy Study of the Equatorial and Upper Port ITER ECH Launchers for an Enhanced Physics Performance

Author

Henderson M.A., Ramponi G., Campbell D., Chavan R., Farina D., Poli E., Saibene G., Sakamoto K., Sauter O., Serikov A., Shidara H., Takahashi K., Zohm H., and Zucca C.

Subjects
____
Abstract

The purpose of the ITER electron cyclotron resonance heating (ECRH) upper port launcher is to stabilize the neoclassical tearing mode (NTM) by driving currents (co-ECCD) locally inside either the q=3/2 or 2 island1. A narrow current deposition profile along with a wide steering range is required to deposit current inside all islands forming at relevant flux surfaces over the wide spectra of possible ITER plasma equilibria. The ITER launcher reference design uses a front steering (FS) mirror that provides optimum focusing for NTM stabilisation and the possibility for a wide steering range. A two-mirror system (focusing and steering) decouples the steering and focusing functions of the launcher for enhanced performance2 over that of a remote steering concept. The steering mechanism uses a frictionless system3, flexure pivots replace traditional bearings and a gas pneumatic actuator replaces mechanical feeds. Two FS launcher designs are under consideration: an NTM launcher providing access over the region in which the NTMs are expected to occur (0.64

Published
2006

15. The ITER ECH FS Upper Launcher mm-wave Design based on a Synergy Study with the Equatorial Launcher

Author

Henderson M.A., Chavan R., Bertizzolo R., Bruschi A., Cirant S., Farina D., Moro A., Ramponi G., Campbell D., Ciattaglia E., Danilov I., Dolizy F., Heidinger R., Kleefeldt K., Landis J.D., Poli E., Saibene G., Sauter O., Serikov A., Shidara H., and Spaeh P.

Subjects
___
Abstract

The ITER ECH heating and current drive system consists of 24 MW (20 MW delivered) at 170GHz, which can be directed to either the equatorial (EL) or upper (UL) port launching antennas (launchers) depending on the desired physics application. The UL reference design uses a front steering (FS) mirror that sweeps the beam in a poloidal plane providing co-ECCD over the outer third of the plasma cross section. A novel frictionless, backlash-free steering mechanism has been developed for an increased reliability. The design avoids components such as bearings and push-pull rods, which tend to grip in conventional launchers in use on present day ECH systems. Flexure pivots replace bearings and a pneumatic seal-less actuator using pressurised helium integrated into the rotating mirror assembly offers a fast and precise response avoiding push-pull rods, linkages representing sliding bearings and remote actuators. The result is a complete self-contained frictionless kinematic assembly rotating the steering mirror up to ±7o (±14º for RF beam). The launcher has a single dedicated purpose of stabilising the neoclassical tearing modes (NTM), with the launcher steering range accessing the region in which the q=3/2 or 2 flux surfaces are expected for scenarios susceptible to NTMs. The performance of the FS launcher far exceeds (by a factor of 1.5 to 3) that required by the physics to stabilize the NTM. The two mirror (focusing and steering) system of the FS launcher essentially decouples the steering and focusing functions of the launcher, offering the flexibility to increase the access range beyond that required by the NTM stabilisation such that the launcher can access further inward for sawteeth control. Extending the range of the UL can relax the EL steering range, which can then be optimised for enhanced performance for improved central deposition and potentially for counter ECCD.

Published
2006

17. The ITER ECH FS Launcher design for an optimized Physics Performance

Author

Henderson M.A., Chavan R., Bertizzolo R., Campbell D., Danilov I., Dolizy F., Farina D., Kleefeldt K., Heidinger R., Landis J.D., Poli E., Ramponi G., Saibene G., Sanchez F., Sauter O., Serikov A., Shidara H., Spaeh H., Zohm H., and Zucca C.

Subjects
___
Abstract

The purpose of the ITER electron cyclotron resonance heating (ECRH) upper port launcher is to stabilize the neoclassical tearing mode (NTM) by driving currents (co-ECCD) locally inside either the q=3/2 or 2 island1. A narrow current deposition profile along with a wide steering range is required to deposit current inside all islands forming at relevant flux surfaces over the wide spectra of possible ITER plasma equilibria. The ITER launcher reference design uses a front steering (FS) mirror that provides optimum focusing for NTM stabilisation and the possibility for a wide steering range. A two-mirror system (focusing and steering) decouples the steering and focusing functions of the launcher for enhanced performance2 over that of a remote steering concept. The steering mechanism uses a frictionless system3, flexure pivots replace traditional bearings and a gas pneumatic actuator replaces mechanical feeds. Two FS launcher designs are under consideration: an NTM launcher providing access over the region in which the NTMs are expected to occur (0.64

Published
2006

20. Engineering progress of the linear IFMIF prototype accelerator (LIPAc)

Author

Gex, D., primary, Beauvais, P.Y., additional, Brañas, B., additional, Bredy, P., additional, Cara, P., additional, Carmona, J.M., additional, Chel, S., additional, Desmons, M., additional, Facco, A., additional, Gastinel, P., additional, Gobin, R., additional, Gournay, J.F., additional, Heidinger, R., additional, Knaster, J., additional, Maebara, S., additional, Marroncle, J., additional, Massaut, V., additional, Matsumoto, H., additional, Mendez, P., additional, Molla, J., additional, Mosnier, A., additional, Nghiem, P., additional, Oliver, C., additional, Orsini, F., additional, Pepato, A., additional, Pisent, A., additional, Podadera, I., additional, Pruneri, G., additional, Shidara, H., additional, Shinto, K., additional, Sugimoto, M., additional, Suzuki, H., additional, Takahashi, H., additional, Toral, F., additional, and Vandeplassche, D., additional

Published
2013
Full Text
View/download PDF

21. Use of a Gold Neutral Beam Probe to Study Fluctuation Suppression During Potential Formation in the GAMMA 10 Tandem Mirror

Author

Yoshikawa, M., primary, Miyata, Y., additional, Mizuguchi, M., additional, Imai, N., additional, Hojo, H., additional, Ichimura, M., additional, Kariya, T., additional, Katanuma, I., additional, Nakashima, Y., additional, Minami, R., additional, Shidara, H., additional, Yamaguchi, Y., additional, Shima, Y., additional, Ohno, Y., additional, Yaguchi, F., additional, and Imai, T., additional

Published
2010
Full Text
View/download PDF

23. Overview of the ITER EC upper launcher

Author

Henderson, M.A., primary, Heidinger, R., additional, Strauss, D., additional, Bertizzolo, R., additional, Bruschi, A., additional, Chavan, R., additional, Ciattaglia, E., additional, Cirant, S., additional, Collazos, A., additional, Danilov, I., additional, Dolizy, F., additional, Duron, J., additional, Farina, D., additional, Fischer, U., additional, Gantenbein, G., additional, Hailfinger, G., additional, Kasparek, W., additional, Kleefeldt, K., additional, Landis, J.-D., additional, Meier, A., additional, Moro, A., additional, Platania, P., additional, Plaum, B., additional, Poli, E., additional, Ramponi, G., additional, Saibene, G., additional, Sanchez, F., additional, Sauter, O., additional, Serikov, A., additional, Shidara, H., additional, Sozzi, C., additional, Spaeh, P., additional, Udintsev, V.S., additional, Zohm, H., additional, and Zucca, C., additional

Published
2008
Full Text
View/download PDF

24. Critical Design Issues of the ITER ECH Front Steering Upper Launcher

Author

Henderson, M. A., primary, Chavan, R., additional, Bertizzolo, R., additional, Campbell, D., additional, Duron, J., additional, Dolizy, F., additional, Heidinger, R., additional, Landis, J.-D., additional, Saibene, G., additional, Sanchez, F., additional, Serikov, A., additional, Shidara, H., additional, and Spaeh, P., additional

Published
2008
Full Text
View/download PDF

25. Recent Electron Cyclotron Emission Results on TCV

Author

Udintsev, V. S., primary, Turri, G., additional, Asp, E., additional, Schlatter, CH., additional, Goodman, T. P., additional, Sauter, O., additional, Weisen, H., additional, Blanchard, P., additional, Coda, S., additional, Duval, B. P., additional, Fable, E., additional, Gudozhnik, A., additional, Isoz, P. F., additional, Henderson, M. A., additional, Klimanov, I., additional, Llobet, X., additional, Marmillod, PH., additional, Mueck, A., additional, Porte, L., additional, Shidara, H., additional, Giruzz, G., additional, Goniche, M., additional, and Turco, F., additional

Published
2007
Full Text
View/download PDF

27. The Enhanced Performance Launcher Design For The ITER Upper Port ECH Antenna

Author

Henderson, M. A., primary, Chavan, R., additional, Bertizzolo, R., additional, Bruschi, A., additional, Criant, S., additional, Duron, J., additional, Farina, D., additional, Heidinger, R., additional, Landis, J.-D., additional, Poli, E., additional, Ramponi, G., additional, Saibene, G., additional, Sauter, O., additional, Sanchez, F., additional, Shidara, H., additional, Udintsev, V. S., additional, Zohm, H., additional, Zucca, C., additional, Ryan, Philip M., additional, and Rasmussen, David, additional

Published
2007
Full Text
View/download PDF

28. H-mode confinement of Heliotron J

Author

Sano, F, primary, Mizuuchi, T, additional, Kondo, K, additional, Nagasaki, K, additional, Okada, H, additional, Kobayashi, S, additional, Hanatani, K, additional, Nakamura, Y, additional, Yamamoto, S, additional, Torii, Y, additional, Suzuki, Y, additional, Shidara, H, additional, Kaneko, M, additional, Arimoto, H, additional, Azuma, T, additional, Arakawa, J, additional, Ohashi, K, additional, Kikutake, M, additional, Shimazaki, N, additional, Hamagami, T, additional, Motojima, G, additional, Yamazaki, H, additional, Yamada, M, additional, Kitagawa, H, additional, Tsuji, T, additional, Nakamura, H, additional, Watanabe, S, additional, Murakami, S, additional, Nishino, N, additional, Yokoyama, M, additional, Ijiri, Y, additional, Senju, T, additional, Yaguchi, K, additional, Sakamoto, K, additional, Tohshi, K, additional, and Shibano, M, additional

Published
2005
Full Text
View/download PDF

29. Safety factor profile requirements for electron ITB formation in TCV

Author

Goodman, T P, primary, Behn, R, additional, Camenen, Y, additional, Coda, S, additional, Fable, E, additional, Henderson, M A, additional, Nikkola, P, additional, Rossel, J, additional, Sauter, O, additional, Scarabosio, A, additional, Zucca, C, additional, Alberti, S, additional, Amorim, P, additional, Andrèbe, Y, additional, Appert, K, additional, Arnoux, G, additional, Bortolon, A, additional, Bottino, A, additional, Chavan, R, additional, Condrea, I, additional, Droz, E, additional, Duval, B P, additional, Etienne, P, additional, Fasel, D, additional, Fasoli, A, additional, Gulejová, B, additional, Hogge, J-P, additional, Horacek, J, additional, Isoz, P-F, additional, Joye, B, additional, Karpushov, A, additional, Kim, S H, additional, Klimanov, I, additional, Lavanchy, P, additional, Lister, J B, additional, Llobet, X, additional, Madeira, T, additional, Magnin, J-C, additional, Marinoni, A, additional, Márki, J, additional, Marlétaz, B, additional, Marmillod, P, additional, Martin, Y, additional, Martynov, An, additional, Maslov, M, additional, Mayor, J-M, additional, Moret, J-M, additional, Mück, A, additional, Paris, P J, additional, Pavlov, I, additional, Perez, A, additional, Pitts, R A, additional, Pochelon, A, additional, Porte, L, additional, Schlatter, Ch, additional, Schombourg, K, additional, Shidara, H, additional, Siegrist, M, additional, Siravo, U, additional, Sushkov, A V, additional, Tonetti, G, additional, Tran, M Q, additional, Weisen, H, additional, Wischmeier, M, additional, Zabolotsky, A, additional, Zhuang, G, additional, and Zhuchkova, A, additional

Published
2005
Full Text
View/download PDF

31. Experimental study of plasma breakdown by second harmonic electron cyclotron waves in Heliotron J

Author

Nagasaki, K, primary, Takahashi, K, additional, Mizuuchi, T, additional, Nishino, N, additional, Nishioka, Y, additional, Shidara, H, additional, Hanatani, K, additional, Okada, H, additional, Kobayashi, S, additional, Yamamoto, S, additional, Kondo, K, additional, Nakamura, Y, additional, Kawazome, H, additional, Kaneko, M, additional, Fukagawa, Y, additional, Obiki, T, additional, and Sano, F, additional

Published
2004
Full Text
View/download PDF

32. Observation of H-Mode Operation Windows for ECH Plasmas in Heliotron J

Author

Sano, F., primary, Mizuuchi, T., additional, Nagasaki, K., additional, Okada, H., additional, Kobayashi, S., additional, Kondo, K., additional, Hanatani, K., additional, Nakamura, Y., additional, Nakasuga, M., additional, Besshou, S., additional, Yamamoto, S., additional, Yokoyama, M., additional, Suzuki, Y., additional, Manabe, Y., additional, Shidara, H., additional, Takamiya, T., additional, Ohno, Y., additional, Nishioka, Y., additional, Yukimoto, H., additional, Takahashi, K., additional, Fukagawa, Y., additional, Kawazome, H., additional, Kaneko, M., additional, Tsuboi, S., additional, Nakazawa, S., additional, Nishio, S., additional, Yamada, M., additional, Ijiri, Y., additional, Senju, T., additional, Yaguchi, K., additional, Sakamoto, K., additional, Tohshi, K., additional, Shibano, M., additional, Tribaldos, V., additional, Tabares, F., additional, and Obiki, T., additional

Published
2004
Full Text
View/download PDF

33. Plasma Confinement Characteristics in Heliotron J—Spontaneous Change of Plasma Confinement State

Author

Mizuuchi, T, primary, Okada, H, additional, Nagasaki, K, additional, Kobayashi, S, additional, Yamamoto, S, additional, Sano, F, additional, Kondo, K, additional, Hanatani, K, additional, Nakasuga, M, additional, Nakamura, Y, additional, Suzuki, Y, additional, Manabe, Y, additional, Shidara, H, additional, Kawazome, H, additional, Kaneko, M, additional, Nishioka, Y, additional, Ohno, Y, additional, Takamiya, T, additional, Yukimoto, H, additional, Fukagawa, Y, additional, Morita, Y, additional, Nakazawa, S, additional, Nishio, S, additional, Takahashi, K, additional, Tuboi, S, additional, Yamada, M, additional, Ohashi, K, additional, Ijiri, Y, additional, Senju, T, additional, Yaguchi, K, additional, Sakamoto, K, additional, Tohshi, K, additional, Shibano, M, additional, and Obiki, T, additional

Published
2004
Full Text
View/download PDF

34. Spectroscopic Study of Impurity Behavior in Heliotron-J Plasmas

Author

Kawazome, Hayato, primary, Tsuboi, Shintaro, additional, Kondo, Katsumi, additional, Mizuuchi, T., additional, Sano, F., additional, Nagasaki, K., additional, Okada, H., additional, Kobayashi, S., additional, Takahashi, K., additional, Shidara, H., additional, Manabe, Y., additional, Kaneko, M., additional, Ohno, Y., additional, Takamiya, T., additional, Nishioka, Y., additional, Yukimoto, H., additional, Nakazawa, S., additional, Nishio, S., additional, Fukagawa, Y., additional, Yamada, M., additional, and Obiki, T., additional

Published
2004
Full Text
View/download PDF

35. Confinement characteristics of ECH plasmas in Heliotron J

Author

Obiki, T, primary, Mizuuchi, T, additional, Okada, H, additional, Nagasaki, K, additional, Sano, F, additional, Kobayashi, S, additional, Hanatani, K, additional, Ijiri, Y, additional, Senju, T, additional, Yaguchi, K, additional, Sakamoto, K, additional, Tohshi, K, additional, Shibano, M, additional, Kondo, K, additional, Nakasuga, M, additional, Nakamura, Y, additional, Wakatani, M, additional, Besshou, S, additional, Manabe, Y, additional, Shidara, H, additional, Ang, W.L, additional, Kawazome, H, additional, Maeno, S, additional, Takeda, M, additional, Tomiyama, K, additional, Tsuru, H, additional, Iriguchi, M, additional, Kaneko, S, additional, Kubo, H, additional, Nishioka, Y, additional, Ohno, Y, additional, Takamiya, T, additional, Yukimoto, H, additional, Fukagawa, Y, additional, Nakazawa, S, additional, Morita, Y, additional, Nishio, S, additional, Takahashi, K, additional, Tsuboi, S, additional, Yamada, M, additional, Nishino, N, additional, Tribaldos, V, additional, and Tabarés, F, additional

Published
2003
Full Text
View/download PDF

36. Electron Bernstein Wave Heating in Heliotron Systems

Author

Nagasaki, K., primary, Yanagi, N., additional, Shidara, H., additional, Sano, F., additional, Kondo, K., additional, Mizuuchi, T., additional, Okada, H., additional, Nakasuga, M., additional, Besshou, S., additional, Manabe, Y., additional, Ang, W. L., additional, Kawazome, H., additional, Maeno, S., additional, Tomiyama, K., additional, Tsuru, H., additional, Takamiya, T., additional, Takeda, M., additional, and Obiki, T., additional

Published
2003
Full Text
View/download PDF

37. The Physics Performance Of The Front Steering Launcher For The ITER ECRH Upper Port.

Author

Henderson, M., Chavan, R., Nikkola, P., Ramponi, G., Saibene, G., Sanchez, F., Sauter, O., Shidara, H., and Zohm, H.

Subjects
PLASMA gases, PLASMA heating, VACUUM, CONTROLLED fusion, PHYSICAL sciences, PLASMA waves
Abstract

The capability of any given e.m.-wave plasma heating system to be utilized for physics applications depends strongly on the technical properties of the launching antenna (or launcher). An effective ECH launcher must project a small mm-wave beam spot size far into the plasma and ‘steer’ the beam across a large fraction of the plasma cross section (along the resonance surface). Thus the choice in the launcher concept and design may either severely limit or enhance the capability of a heating system to be effectively applied for physics applications, such as sawtooth stabilization, control of the Neoclassical Tearing Mode (NTM), Edge Localized Mode (ELM) control, etc. Presently, two antenna concepts are under consideration for the ITER upper port ECH launcher: front steering (FS) and remote steering (RS) launchers. The RS launcher has the technical advantage of easier maintenance access to the steering mirror, which is isolated from the torus vacuum. The FS launcher places the steering mirror near the plasma increasing the technical challenges, but significantly enhancing the focusing and steering capabilities of the launcher, offering a threefold increase in NTM stabilization efficiency over the RS launcher as well as the potential for application to other critical physics issues such as ELM or sawtooth control. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

Published
2005
Full Text
View/download PDF

38. First plasmas in Heliotron J

Author

Obiki, T, primary, Mizuuchi, T, additional, Nagasaki, K, additional, Okada, H, additional, Sano, F, additional, Hanatani, K, additional, Liu, Y, additional, Hamada, T, additional, Manabe, Y, additional, Shidara, H, additional, Ang, W.L, additional, Ikeda, Y, additional, Kobayashi, T, additional, Takamiya, T, additional, Takeda, M, additional, Ijiri, Y, additional, Senju, T, additional, Yaguchi, K, additional, Sakamoto, K, additional, Toshi, K, additional, Shibano, M, additional, Kondo, K, additional, Besshou, S, additional, Nakamura, Y, additional, Nakasuga, M, additional, Wakatani, M, additional, Yamagishi, O, additional, Aizawa, K, additional, Kawazome, Y, additional, Maeno, S, additional, and Tomiyama, K, additional

Published
2001
Full Text
View/download PDF

40. Confinement characteristics of ECH plasmas in Heliotron J.

Author

Obiki, T., Mizuuchi, T., Okada, H., Nagasaki, K., Sano, F., Kobayashi, S., Hanatani, K., Ijiri, Y., Senju, T., K. Yaguchi, Sakamoto, K., Tohshi, K., Shibano, M., Kondo, K., Nakasuga, M., Nakamura, Y., Wakatani, M., Besshou, S., Manabe, Y., and Shidara, H.

Published
2004

41. Progress on the ITER Upper Launcher Millimeter-Wave Design and Testing

Author

Collazos, A., Udintsev, V. S., Chavan, R., Felici, F., Dolizy, F., Henderson, M. A., and Shidara, H.

Abstract

AbstractThe aim of the ITER electron cyclotron heating and current drive upper launcher (UL) is to control magnetohydrodynamic activity in the plasma, in particular neoclassical tearing modes, requiring a narrow and peaked deposition of the radio-frequency (rf) power.The millimeter-wave (mm-wave) system of the UL is optimized to ensure that the eight rf beams are all focused to a small beam width at the resonance location. The present design uses two mitre bends per beam and a focusing mirror for each set of four beams, orientating each set onto a single steering mirror (SM) to inject it into the plasma. The SM is rotated using a frictionless and backlash free pneumo-mechanical system. A first prototype of the SM has been constructed to demonstrate the manufacturability and the actuation principle and to develop an adequate control strategy.A test program has been developed to ensure the integrity of the launcher from the pre-build-to-print design phase (research and development) up to the tests after maintenance.This paper presents a general overview of the system, a description of the progress in the mm-wave optical layout, low-power tests, alignment specifications of the mm-wave components, and SM capabilities to meet the ITER requirements.

Published
2009
Full Text
View/download PDF

42. International Fusion Materials Irradiation Facility injector acceptance tests at CEA/Saclay: 140 mA/100 keV deuteron beam characterization.

Author

Gobin, R., Bogard, D., Cara, P., Chauvin, N., Chel, S., Delferrière, O., Harrault, F., Mattei, P., Mosnier, A., Senée, F., Shidara, H., and Okumura, Y.

Subjects
IRRADIATION, NEUTRON flux, PLASMA diagnostics, PARTICLES (Nuclear physics), NUCLEAR physics instruments, EQUIPMENT & supplies
Abstract

In the framework of the ITER broader approach, the International Fusion Materials Irradiation Facility (IFMIF) deuteron accelerator (2 x 125 mA at 40 MeV) is an irradiation tool dedicated to high neutron flux production for future nuclear plant material studies. During the validation phase, the Linear IFMIF Prototype Accelerator (LIPAc) machine will be tested on the Rokkasho site in Japan. This demonstrator aims to produce 125 mA/9 MeV deuteron beam. Involved in the LIPAc project for several years, specialists from CEA/Saclay designed the injector based on a SILHI type ECR source operating at 2.45 GHz and a 2 solenoid low energy beam line to produce such high intensity beam. The whole injector, equipped with its dedicated diagnostics, has been then installed and tested on the Saclay site. Before shipment from Europe to Japan, acceptance tests have been performed in November 2012 with 100 keV deuteron beam and intensity as high as 140 mA in continuous and pulsed mode. In this paper, the emittance measurements done for different duty cycles and different beam intensities will be presented as well as beam species fraction analysis. Then the reinstallation in Japan and commissioning plan on site will be reported. [ABSTRACT FROM AUTHOR]

Published
2014
Full Text
View/download PDF

43. Plasma breakdown using second-harmonic EC waves in helical devices

Author

Nagasaki, K., Mizuuchi, T., Sano, F., Okada, H., Kobayashi, S., Cappa, A., Francisco Castejón, Fernández, A., La Cal, E., Estrada, T., Tribaldos, V., Tabarés, F., Tafalla, D., Yoshimura, Y., Kondo, K., Takahashi, K., and Shidara, H.

Subjects
Physics::Plasma Physics, Physics::Space Physics
Abstract

Plasma breakdown using second-harmonic electron cyclotron (EC) waves has been studied experimentally in three helical devices, Heliotron J, TJ-II and CHS. Recent technological progress on electron cyclotron heating (ECH) systems enables us to determine what the important factors for second-harmonic plasma breakdown are. Comparison of the experimental results among three devices shows a common feature that the plasma starts up from the good confinement region and strongly depends on the nonlinear interactions with the electric field of the local beam rather than the multi-reflected field. This suggests that the confinement of high energy electrons generated by ECH has a dominant role in second-harmonic plasma breakdown.

44. ECRH beam Optics optimization for ITER upper port launcher

Author

Shidara H., Henderson M.A., Chavan R., Farina D., Poli E., and Ramponi G.

Subjects
___
Abstract

The electron cyclotron resonance heating (ECRH) launchers are going to be installed in four ITER upper ports for stabilizing the neoclassical tearing mode (NTM) by driving currents (co-ECCD) locally inside either the q = 3/2 or 2 island. The efficiency in stabilizing the NTM depends on the peak current density (jCD), relative to the local bootstrap current. The mm-wave optical design has been optimized to provide the largest jCD over the region, where NTMs are expected to occur in the plasma cross section. The optimization has been carried out for two designs: one applied only to NTM stabilization and another for Extended Physics launcher for an enhanced ITER ECRH physics programme. The main limitation to the optical system is the spatial restrictions of the port plug and blanket shield module. The ECRH launcher has 8 beams (4 beams × 2 vertical rows) per port, with each beam incident on a focusing and steering mirror. The beam optics has been optimized by overlapping 4 beams on each mirror, this overlap maximizes the beam spot size (~64mm) on the focusing mirror within the available space, which can focus a narrow beam waist (~21 mm) far into the plasma (~2 m). The output beam characters can be controlled by modifying the focusing mirror curvature.

45. Recent electron cyclotron emission results on TCV

Author

Udintsev, V. S., Turri, G., Asp, E., Schlatter, C., Goodman, T. P., Sauter, O., Weisen, H., Blanchard, P., Coda, S., Duval, B. P., Fable, E., Gudozhnik, A., Isoz, P. F., Henderson, M. A., Klimanov, I., Llobet, X., Marmillod, P. H., Mueck, A., Porte, L., and Shidara, H.

Subjects
Physics::Plasma Physics
Abstract

Electron cyclotron emission (ECE) diagnostics on Tokamak a Configuration Variable (TCV) allow study of the electron temperature evolution in time with good spatial and temporal resolution at the high field side and low field side at various lines of sight. That is why ECE is being widely used to obtain both qualitative and quantitative information on heat transport, magnetohydrodynamics (MHD) phenomena, and fast electron dynamics. In this paper, a new regime on TCV with regular oscillations of the electron temperature in electron cyclotron current drive (ECCD) driven fully noninductive discharges and in discharges with a combination of ohmic/ECCD driven current is discussed These oscillations are reminiscent of the oscillations of the central electron temperature (O-regime) seen on Tore Supra in fully noninductive lower hybrid current drive plasmas. A link between evolutions of the electron temperature, the MHD modes, and the current density profile on TCV is considered In order to yield information on the properties of microturbulence of electrostatic and magnetic origin on TCV, a correlation ECE radiometer is currently under development. A technical description of the diagnostic is presented in this paper.

48. mm-wave Optical System of the ITER Upper Port EC Launcher

Author

Henderson, M.A., Chavan, R., Bertizzolo, R., Bruschi, A., Cirant, S., Collazos, A., Dolizy, F., Farina, D., Kasparek, W., Landis, J.-D., Moro, A., Platina, P., Plaum, B., Poli, E., Ramponi, G., Saibene, G., Sanchez, F., Shidara, H., and Udintsev, V.S.

Catalog

Books, media, physical & digital resources
See catalog results