Search

Your search keyword '"Tokuzawa, T."' showing total 537 results
Start Over Author "Tokuzawa, T."
537 results on '"Tokuzawa, T."'

1. Turbulence Transition in Magnetically Confined Hydrogen and Deuterium Plasmas

Author

Kinoshita, T., primary, Tanaka, K., additional, Ishizawa, A., additional, Sakai, H., additional, Nunami, M., additional, Ohtani, Y., additional, Yamada, H., additional, Sato, M., additional, Nakata, M., additional, Tokuzawa, T., additional, Yasuhara, R., additional, Takemura, Y., additional, Yamada, I., additional, Funaba, H., additional, Ida, K., additional, Yoshinuma, M., additional, Tsujimura, T., additional, Seki, R., additional, Ichiguchi, K., additional, and Michael, C. A., additional

Published
2024
Full Text
View/download PDF

2. Rotational movement analysis based on Fourier-rectangular function transform for cylindrical plasma.

Author

Nishimura, D., Fujisawa, A., Yamasaki, K., Nagashima, Y., Moon, C., Nishizawa, T., Kobayashi, T.-K., Kobayashi, T., Shimizu, A., Tokuzawa, T., and Ido, T.

Subjects
CYLINDRICAL plasmas, STELLAR oscillations, PLASMA dynamics
Abstract

This article presents a method to estimate the rotational velocity of a cylindrical plasma from its two-dimensional images by an extended use of the Fourier-rectangular function transform, which was proposed to analyze the structure and dynamics of a cylindrical plasma [K. Yamasaki e t a l., J. Appl. Phys. 126 , 043304 (2019)]. The proposed method is applied to tomography images of plasmas produced in a linear cylindrical device and succeeds in obtaining the radial distribution of rotational velocity and its fluctuations, providing an interesting finding, that is, the existence of flow modulation associated with m = 1 mode fluctuations. [ABSTRACT FROM AUTHOR]

Published
2023
Full Text
View/download PDF

7. Isotope effects on transport characteristics of edge and core plasmas heated by neutral beam injection (NBI) in an inward shifted configuration at the Large Helical Device

Author

Zhou, H., primary, Xu, Y., additional, Kobayashi, M., additional, Shimizu, A., additional, Seki, R., additional, Tanaka, K., additional, Tokuzawa, T., additional, Yoshinuma, M., additional, Takemura, Y., additional, Takahashi, H., additional, Ogawa, K., additional, Cheng, J., additional, Li, W., additional, Wu, D.N., additional, Zhu, Y.J., additional, Luo, Y., additional, Li, Y.C., additional, Huang, J., additional, Wang, X.Q., additional, Liu, H.F., additional, Liu, H., additional, and Zhang, X., additional

Published
2024
Full Text
View/download PDF

8. Overview of multiscale turbulence studies covering ion-to-electron scales in magnetically confined fusion plasma.

Author

Maeyama, S., Howard, N.T., Citrin, J., Watanabe, T.-H., and Tokuzawa, T.

Subjects
PLASMA turbulence, PLASMA confinement, TURBULENCE, EDDY flux, LARMOR radius, PLASMA interactions
Abstract

Turbulent transport in magnetically confined fusion plasma has conventionally been analyzed at the ion gyroradius scale based on the microturbulence theory. However, ion-scale turbulence analysis sometimes fails to predict the turbulent transport flux observed experimentally. Microturbulence at the electron gyroradius scale and cross-scale interactions between disparate-scale turbulences are possible mechanisms to resolve this issue. This overview discusses the recent progress in multiscale turbulence studies and presents future perspectives from recent experimental, theoretical, and numerical investigations. The following aspects are highlighted: (1) the importance of electron-scale effects in experiments, (2) the physical mechanisms of cross-scale interactions, (3) modeling electron-scale effects in quasilinear transport models, and (4) the impacts of cross-scale interactions on burning plasmas. Understanding multiscale turbulence is necessary to improve performance prediction and explore optimal operations for future burning plasmas. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

10. Estimation of plasma parameter profiles and their derivatives from linear observations by using Gaussian processes

Author

Nishizawa, T, primary, Tokuda, S, additional, Kobayashi, T, additional, Tanaka, K, additional, Funaba, H, additional, Yamada, I, additional, Takemura, Y, additional, Tokuzawa, T, additional, Yasuhara, R, additional, Uehara, H, additional, Ida, K, additional, Takahashi, H, additional, Kawachi, Y, additional, Inagaki, S, additional, Kado, S, additional, Sasaki, M, additional, and Fujisawa, A, additional

Published
2023
Full Text
View/download PDF

15. Studies of energetic particle transport induced by multiple Alfvén eigenmodes using neutron and escaping energetic particle diagnostics in Large Helical Device deuterium plasmas

Author

Ogawa, K., primary, Isobe, M., additional, Kamio, S., additional, Nuga, H., additional, Seki, R., additional, Sangaroon, S., additional, Yamaguchi, H., additional, Fujiwara, Y., additional, Takada, E., additional, Murakami, S., additional, Jo, J., additional, Takemura, Y., additional, Sakai, H., additional, Tanaka, K., additional, Tokuzawa, T., additional, Yasuhara, R., additional, and Osakabe, M., additional

Published
2022
Full Text
View/download PDF

16. Plasma physics and control studies planned in JT-60SA for ITER and DEMO operations and risk mitigation

Author

Yoshida, M, primary, Giruzzi, G, additional, Aiba, N, additional, Artaud, J F, additional, Ayllon-Guerola, J, additional, Balbinot, L, additional, Beeke, O, additional, Belonohy, E, additional, Bettini, P, additional, Bin, W, additional, Bierwage, A, additional, Bolzonella, T, additional, Bonotto, M, additional, Boulbe, C, additional, Buermans, J, additional, Chernyshova, M, additional, Coda, S, additional, Coelho, R, additional, Davis, S, additional, Day, C, additional, De Tommasi, G, additional, Dibon, M, additional, Ejiri, A, additional, Falchetto, G, additional, Fassina, A, additional, Faugeras, B, additional, Figini, L, additional, Fukumoto, M, additional, Futatani, S, additional, Galazka, K, additional, Garcia, J, additional, Garcia-Muñoz, M, additional, Garzotti, L, additional, Giacomelli, L, additional, Giudicotti, L, additional, Hall, S, additional, Hayashi, N, additional, Hoa, C, additional, Honda, M, additional, Hoshino, K, additional, Iafrati, M, additional, Iantchenko, A, additional, Ide, S, additional, Iio, S, additional, Imazawa, R, additional, Inoue, S, additional, Isayama, A, additional, Joffrin, E, additional, Kamiya, K, additional, Ko, Y, additional, Kobayashi, M, additional, Kobayashi, T, additional, Kocsis, G, additional, Kovacsik, A, additional, Kurki-Suonio, T, additional, Lacroix, B, additional, Lang, P, additional, Lauber, Ph, additional, Louzguiti, A, additional, de la Luna, E, additional, Marchiori, G, additional, Mattei, M, additional, Matsuyama, A, additional, Mazzi, S, additional, Mele, A, additional, Michel, F, additional, Miyata, Y, additional, Morales, J, additional, Moreau, P, additional, Moro, A, additional, Nakano, T, additional, Nakata, M, additional, Narita, E, additional, Neu, R, additional, Nicollet, S, additional, Nocente, M, additional, Nowak, S, additional, Orsitto, F P, additional, Ostuni, V, additional, Ohtani, Y, additional, Oyama, N, additional, Pasqualotto, R, additional, Pégourié, B, additional, Perelli, E, additional, Pigatto, L, additional, Piccinni, C, additional, Pironti, A, additional, Platania, P, additional, Ploeckl, B, additional, Ricci, D, additional, Roussel, P, additional, Rubino, G, additional, Sano, R, additional, Särkimäki, K, additional, Shinohara, K, additional, Soare, S, additional, Sozzi, C, additional, Sumida, S, additional, Suzuki, T, additional, Suzuki, Y, additional, Szabolics, T, additional, Szepesi, T, additional, Takase, Y, additional, Takech, M, additional, Tamura, N, additional, Tanaka, K, additional, Tanaka, H, additional, Tardocchi, M, additional, Terakado, A, additional, Tojo, H, additional, Tokuzawa, T, additional, Torre, A, additional, Tsujii, N, additional, Tsutsui, H, additional, Ueda, Y, additional, Urano, H, additional, Valisa, M, additional, Vallar, M, additional, Vega, J, additional, Villone, F, additional, Wakatsuki, T, additional, Wauters, T, additional, Wischmeier, M, additional, Yamoto, S, additional, and Zani, L, additional

Published
2022
Full Text
View/download PDF

17. Direct observation of the non-locality of non-diffusive counter-gradient electron thermal transport during the formation of hollow electron-temperature profiles in the Large Helical Device

Author

Tsujimura, T. I., primary, Kobayashi, T., additional, Tanaka, K., additional, Ida, K., additional, Nagaoka, K., additional, Yoshinuma, M., additional, Yamada, I., additional, Funaba, H., additional, Seki, R., additional, Satake, S., additional, Kinoshita, T., additional, Tokuzawa, T., additional, Kenmochi, N., additional, Igami, H., additional, Mukai, K., additional, Goto, M., additional, and Kawamoto, Y., additional

Published
2022
Full Text
View/download PDF

18. Completion of JT-60SA construction and contribution to ITER

Author

Kamada Y., Di Pietro E., Hanada M., Barabaschi P., Ide S., Davis S., Yoshida M., Giruzzi G., Sozzi C., Abdel Maksoud W., Abe H., Aiba N., Akiyama T., Ayllon-Guerola J., Arai T., Artaud J. -F., Asakura N., Ashikawa N., Balbinot L., Bando T., Baulaigue O., Belonohy E., Bin W., Bombarda F., Bolzonella T., Bonne F., Bonotto M., Botija J., Cabrera-Perez S., Cardella A., Carraro L., Cavalier J., Chernyshova M., Chiba S., Clement-Lorenzo S., Cocilovo V., Coda S., Coelho R., Coffey I., Collin B., Corato V., Cucchiaro A., Czarski T., Dairaku M., Day C., de la Luna E., De Tommasi G., Decool P., Di Pace L., Dibon M., Disset G., Ejiri A., Endo Y., Ezumi N., Falchetto G., Fassina A., Fejoz P., Ferro A., Fietz W., Figini L., Fornal T., Frello G., Fujita T., Fukuda T., Fukui K., Fukumoto M., Furukawa M., Futatani S., Gabellieri L., Gaio E., Galazka K., Garcia J., Garcia-Dominguez J., Garcia-Lopez J., Garcia-Munoz M., Garzotti L., Gasparini F., Gharafi S., Giacomelli L., Ginoulhiac G., Giudicotti L., Guillen Gonzalez R., Hajnal N., Hall S., Hamada K., Hanada K., Hasegawa K., Hatae T., Hatakeyama S., Hauer V., Hayashi N., Hayashi T., Heller R., Higashijima S., Hinata J., Hiranai S., Hiratsuka J., Hiwatari R., Hoa C., Homma H., Honda A., Honda M., Horiike H., Hoshino K., Hurzlmeier H., Iafrati M., Ibano K., Ichige H., Ichikawa M., Ichimura M., Ida K., Idei H., Iijima T., Iio S., Ikeda R., Ikeda Y., Imai T., Imazawa R., Inagaki S., Inomoto M., Inoue S., Isayama A., Ishida S., Ishii Y., Isobe M., Janky F., Joffrin E., Jokinen A., Kado S., Kajita S., Kajiwara K., Kamata I., Kaminaga A., Kamiya K., Kanapienyte D., Kashiwa Y., Kashiwagi M., Katayama K., Kawamata Y., Kawamura G., Kawano K., Kawashima H., Kin F., Kitajima S., Kiyono K., Kizu K., Kobayashi K., Kobayashi M., Kobayashi S., Kobayashi T., Kocsis G., Koide Yo., Koide Yu., Kojima A., Kokusen S., Komuro K., Konishi S., Kovacsik A., Ksiazek I., Kubkowska M., Kuhner G., Kuramochi M., Kurihara K., Kurki-Suonio T., Kurniawan A. B., Kuwata T., Lacroix B., Lamaison V., Lampasi A., Lang P., Lauber P., Lawson K., Louzguiti A., Maekawa R., Maekawa T., Maeyama S., Maffia G., Maget P., Mailloux J., Maione I., Maistrello A., Malinowski K., Marchiori G., Marechal J. -L., Massaut V., Masuzaki S., Matsunaga G., Matsunaga S., Mayri Ch., Mattei M., Medrano M., Mele A., Meyer I., Michel F., Minami T., Miyata Y., Miyazawa J., Miyo Y., Mizuuchi T., Mogaki K., Morales J., Moreau P., Mori M., Morisaki T., Morishima S., Moriyama S., Moro A., Murakami H., Murayama M., Murakami S., Nagasaki K., Naito O., Nakamura S., Nakano T., Nakashima Y., Nardino V., Narita E., Narushima Y., Natsume K., Nemoto S., Neu R., Nicollet S., Nishikawa M., Nishimura S., Nishiura M., Nishiyama T., Nocente M., Nobuta Y., Novello L., Nunio F., Ochoa S., Ogawa T., Ogawa Y., Ohdachi S., Ohmori Y., Ohno N., Ohtani Y., Ohzeki M., Oishi T., Okano F., Okano J., Okano K., Onishi Y., Osakabe M., Oshima T., Ostuni V., Oya M., Oya Y., Oyama N., Ozeki T., Pasqualotto R., Pelli S., Peretti E., Phillips G., Piccinni C., Pigatto L., Pironti A., Pizzuto A., Plockl B., Polli G., Poncet J. -M., Ponsot P., Puiatti M., Radloff D., Raimondi V., Ramos F., Rancsik P., Ricci D., Ricciarini S., Rincon E., Romano A., Rossi P., Roussel P., Rubino G., Saeki H., Sagara A., Sakakibara S., Sakamoto H., Sakamoto M., Sakamoto Y., Sakasai A., Sakata S., Sakuma T., Sakurai S., Salanon B., Salmi A., Sannazzaro G., Sano R., Sanpei A., Sasajima T., Sasaki S., Sasao H., Sato F., Sato M., Sawahata M., Scherber A., Scully S., Seki M., Seki S., Shibama Y., Shibata Y., Shikama T., Shimada K., Shimono M., Shinde J., Shinya T., Shinohara K., Shirai H., Shiraishi J., Soare S., Soleto A., Someya Y., Streciwilk-Kowalska E., Strobel H., Sueoka M., Sukegawa A., Sulistyanintyas D., Sumida S., Sunaoshi H., Suzuki H., Suzuki M., Suzuki S., Suzuki T., Suzuki Y., Svoboda J., Szabolics T., Szepesi T., Takahashi K., Takase Y., Takechi M., Takeda K., Takeiri Y., Takenaga H., Taliercio C., Tamura N., Tanaka H., Tanaka K., Tani K., Tanigawa H., Tardocchi M., Terakado A., Terakado M., Terakado T., Teuchner B., Tilia B., Tobita K., Toi K., Toida N., Tojo H., Tokitani M., Tokuzawa T., Tormarchio V., Tomine M., Torre A., Totsuka T., Tsuchiya K., Tsujii N., Tsuru D., Tsutsui H., Uchida M., Ueda Y., Uno J., Urano H., Usui K., Utoh H., Valisa M., Vallar M., Vallcorba-Carbonell R., Vallet J. -C., Varela J., Vega J., Verrecchia M., Vieillard L., Villone F., Vincenzi P., Wada K., Wada R., Wakatsuki T., Wanner M., Watanabe F., Watanabe K., Wauters T., Wiesen S., Wischmeier M., Yagi M., Yagyu J., Yajima M., Yokooka S., Yokoyama M., Yamamoto S., Yamanaka H., Yamauchi K., Yamauchi Y., Yamazaki H., Yamazaki K., Yamazaki R., Yamoto S., Yanagi S., Yanagihara K., Yoshizawa N., Zani L., Zito P., Kamada, Y., Di Pietro, E., Hanada, M., Barabaschi, P., Ide, S., Davis, S., Yoshida, M., Giruzzi, G., Sozzi, C., Abdel Maksoud, W., Abe, H., Aiba, N., Akiyama, T., Ayllon-Guerola, J., Arai, T., Artaud, J. -F., Asakura, N., Ashikawa, N., Balbinot, L., Bando, T., Baulaigue, O., Belonohy, E., Bin, W., Bombarda, F., Bolzonella, T., Bonne, F., Bonotto, M., Botija, J., Cabrera-Perez, S., Cardella, A., Carraro, L., Cavalier, J., Chernyshova, M., Chiba, S., Clement-Lorenzo, S., Cocilovo, V., Coda, S., Coelho, R., Coffey, I., Collin, B., Corato, V., Cucchiaro, A., Czarski, T., Dairaku, M., Day, C., de la Luna, E., De Tommasi, G., Decool, P., Di Pace, L., Dibon, M., Disset, G., Ejiri, A., Endo, Y., Ezumi, N., Falchetto, G., Fassina, A., Fejoz, P., Ferro, A., Fietz, W., Figini, L., Fornal, T., Frello, G., Fujita, T., Fukuda, T., Fukui, K., Fukumoto, M., Furukawa, M., Futatani, S., Gabellieri, L., Gaio, E., Galazka, K., Garcia, J., Garcia-Dominguez, J., Garcia-Lopez, J., Garcia-Munoz, M., Garzotti, L., Gasparini, F., Gharafi, S., Giacomelli, L., Ginoulhiac, G., Giudicotti, L., Guillen Gonzalez, R., Hajnal, N., Hall, S., Hamada, K., Hanada, K., Hasegawa, K., Hatae, T., Hatakeyama, S., Hauer, V., Hayashi, N., Hayashi, T., Heller, R., Higashijima, S., Hinata, J., Hiranai, S., Hiratsuka, J., Hiwatari, R., Hoa, C., Homma, H., Honda, A., Honda, M., Horiike, H., Hoshino, K., Hurzlmeier, H., Iafrati, M., Ibano, K., Ichige, H., Ichikawa, M., Ichimura, M., Ida, K., Idei, H., Iijima, T., Iio, S., Ikeda, R., Ikeda, Y., Imai, T., Imazawa, R., Inagaki, S., Inomoto, M., Inoue, S., Isayama, A., Ishida, S., Ishii, Y., Isobe, M., Janky, F., Joffrin, E., Jokinen, A., Kado, S., Kajita, S., Kajiwara, K., Kamata, I., Kaminaga, A., Kamiya, K., Kanapienyte, D., Kashiwa, Y., Kashiwagi, M., Katayama, K., Kawamata, Y., Kawamura, G., Kawano, K., Kawashima, H., Kin, F., Kitajima, S., Kiyono, K., Kizu, K., Kobayashi, K., Kobayashi, M., Kobayashi, S., Kobayashi, T., Kocsis, G., Koide, Yo., Koide, Yu., Kojima, A., Kokusen, S., Komuro, K., Konishi, S., Kovacsik, A., Ksiazek, I., Kubkowska, M., Kuhner, G., Kuramochi, M., Kurihara, K., Kurki-Suonio, T., Kurniawan, A. B., Kuwata, T., Lacroix, B., Lamaison, V., Lampasi, A., Lang, P., Lauber, P., Lawson, K., Louzguiti, A., Maekawa, R., Maekawa, T., Maeyama, S., Maffia, G., Maget, P., Mailloux, J., Maione, I., Maistrello, A., Malinowski, K., Marchiori, G., Marechal, J. -L., Massaut, V., Masuzaki, S., Matsunaga, G., Matsunaga, S., Mayri, Ch., Mattei, M., Medrano, M., Mele, A., Meyer, I., Michel, F., Minami, T., Miyata, Y., Miyazawa, J., Miyo, Y., Mizuuchi, T., Mogaki, K., Morales, J., Moreau, P., Mori, M., Morisaki, T., Morishima, S., Moriyama, S., Moro, A., Murakami, H., Murayama, M., Murakami, S., Nagasaki, K., Naito, O., Nakamura, S., Nakano, T., Nakashima, Y., Nardino, V., Narita, E., Narushima, Y., Natsume, K., Nemoto, S., Neu, R., Nicollet, S., Nishikawa, M., Nishimura, S., Nishiura, M., Nishiyama, T., Nocente, M., Nobuta, Y., Novello, L., Nunio, F., Ochoa, S., Ogawa, T., Ogawa, Y., Ohdachi, S., Ohmori, Y., Ohno, N., Ohtani, Y., Ohzeki, M., Oishi, T., Okano, F., Okano, J., Okano, K., Onishi, Y., Osakabe, M., Oshima, T., Ostuni, V., Oya, M., Oya, Y., Oyama, N., Ozeki, T., Pasqualotto, R., Pelli, S., Peretti, E., Phillips, G., Piccinni, C., Pigatto, L., Pironti, A., Pizzuto, A., Plockl, B., Polli, G., Poncet, J. -M., Ponsot, P., Puiatti, M., Radloff, D., Raimondi, V., Ramos, F., Rancsik, P., Ricci, D., Ricciarini, S., Rincon, E., Romano, A., Rossi, P., Roussel, P., Rubino, G., Saeki, H., Sagara, A., Sakakibara, S., Sakamoto, H., Sakamoto, M., Sakamoto, Y., Sakasai, A., Sakata, S., Sakuma, T., Sakurai, S., Salanon, B., Salmi, A., Sannazzaro, G., Sano, R., Sanpei, A., Sasajima, T., Sasaki, S., Sasao, H., Sato, F., Sato, M., Sawahata, M., Scherber, A., Scully, S., Seki, M., Seki, S., Shibama, Y., Shibata, Y., Shikama, T., Shimada, K., Shimono, M., Shinde, J., Shinya, T., Shinohara, K., Shirai, H., Shiraishi, J., Soare, S., Soleto, A., Someya, Y., Streciwilk-Kowalska, E., Strobel, H., Sueoka, M., Sukegawa, A., Sulistyanintyas, D., Sumida, S., Sunaoshi, H., Suzuki, H., Suzuki, M., Suzuki, S., Suzuki, T., Suzuki, Y., Svoboda, J., Szabolics, T., Szepesi, T., Takahashi, K., Takase, Y., Takechi, M., Takeda, K., Takeiri, Y., Takenaga, H., Taliercio, C., Tamura, N., Tanaka, H., Tanaka, K., Tani, K., Tanigawa, H., Tardocchi, M., Terakado, A., Terakado, M., Terakado, T., Teuchner, B., Tilia, B., Tobita, K., Toi, K., Toida, N., Tojo, H., Tokitani, M., Tokuzawa, T., Tormarchio, V., Tomine, M., Torre, A., Totsuka, T., Tsuchiya, K., Tsujii, N., Tsuru, D., Tsutsui, H., Uchida, M., Ueda, Y., Uno, J., Urano, H., Usui, K., Utoh, H., Valisa, M., Vallar, M., Vallcorba-Carbonell, R., Vallet, J. -C., Varela, J., Vega, J., Verrecchia, M., Vieillard, L., Villone, F., Vincenzi, P., Wada, K., Wada, R., Wakatsuki, T., Wanner, M., Watanabe, F., Watanabe, K., Wauters, T., Wiesen, S., Wischmeier, M., Yagi, M., Yagyu, J., Yajima, M., Yokooka, S., Yokoyama, M., Yamamoto, S., Yamanaka, H., Yamauchi, K., Yamauchi, Y., Yamazaki, H., Yamazaki, K., Yamazaki, R., Yamoto, S., Yanagi, S., Yanagihara, K., Yoshizawa, N., Zani, L., and Zito, P.

Subjects
assembly, Cryostat, Nuclear and High Energy Physics, Materials science, Tokamak, Nuclear engineering, Plasma, Condensed Matter Physics, Field coil, ITER risk mitigation, Overcurrent, law.invention, Control theory, law, Electromagnetic coil, research plan, broader approach, Voltage
Abstract

Construction of the JT-60SA tokamak was completed on schedule in March 2020. Manufacture and assembly of all the main tokamak components satisfied technical requirements, including dimensional accuracy and functional performances. Development of the plasma heating systems and diagnostics have also progressed, including the demonstration of the favourable electron cyclotron range of frequency (ECRF) transmission at multiple frequencies and the achievement of long sustainment of a high-energy intense negative ion beam. Development of all the tokamak operation control systems has been completed, together with an improved plasma equilibrium control scheme suitable for superconducting tokamaks including ITER. For preparation of the tokamak operation, plasma discharge scenarios have been established using this advanced equilibrium controller. Individual commissioning of the cryogenic system and the power supply system confirmed that these systems satisfy design requirements including operational schemes contributing directly to ITER, such as active control of heat load fluctuation of the cryoplant, which is essential for dynamic operation in superconducting tokamaks. The integrated commissioning (IC) is started by vacuum pumping of the vacuum vessel and cryostat, and then moved to cool-down of the tokamak and coil excitation tests. Transition to the super-conducting state was confirmed for all the TF, EF and CS coils. The TF coil current successfully reached 25.7 kA, which is the nominal operating current of the TF coil. For this nominal toroidal field of 2.25 T, ECRF was applied and an ECRF plasma was created. The IC was, however, suspended by an incident of over current of one of the superconducting equilibrium field coil and He leakage caused by insufficient voltage holding capability at a terminal joint of the coil. The unique importance of JT-60SA for H-mode and high-β steady-state plasma research has been confirmed using advanced integrated modellings. These experiences of assembly, IC and plasma operation of JT-60SA contribute to ITER risk mitigation and efficient implementation of ITER operation.

Published
2022

20. ICRF Physics Measurements by Reflectometry

Author

Mase, A., Hojo, H., Kobayashi, M., Oyama, N., Bruskin, L. G., Doyle, E. J., Tokuzawa, T., Itakura, A., Ichimura, M., Tamano, T., Stott, Peter E., editor, Gorini, Giuseppe, editor, and Sindoni, Elio, editor

Published
1996
Full Text
View/download PDF

21. Isotope effects on transport in LHD

Author

Tanaka, K, primary, Nagaoka, K, additional, Ida, K, additional, Yamada, H, additional, Kobayashi, T, additional, Satake, S, additional, Nakata, M, additional, Kinoshita, T, additional, Ohtani, Y, additional, Tokuzawa, T, additional, Takahashi, H, additional, Warmer, F, additional, Mukai, K, additional, Murakami, S, additional, Sakamoto, R, additional, Nakano, H, additional, Osakabe, M, additional, Morisaki, T, additional, Nunami, M, additional, Tala, T, additional, Tsujimura, T, additional, Takemura, Y, additional, Yokoyama, M, additional, Seki, R, additional, Igami, H, additional, Yoshimura, Y, additional, Kubo, S, additional, Shimozuma, T, additional, Akiyama, T, additional, Yamada, I, additional, Yasuhara, R, additional, Funaba, H, additional, Yoshinuma, M, additional, Goto, M, additional, Oishi, T, additional, Morita, S, additional, Motojima, G, additional, Shoji, M, additional, Masuzaki, S, additional, Michael, C A, additional, and Vacheslavov, L N, additional

Published
2021
Full Text
View/download PDF

24. Improved performance of electron cyclotron resonance heating by perpendicular injection in the Large Helical Device

Author

Tsujimura, T.I., primary, Yanai, R., additional, Mizuno, Y., additional, Tanaka, K., additional, Yoshimura, Y., additional, Tokuzawa, T., additional, Nishiura, M., additional, Sakamoto, R., additional, Motojima, G., additional, Kubo, S., additional, Shimozuma, T., additional, Igami, H., additional, Takahashi, H., additional, Yoshinuma, M., additional, and Ohshima, S., additional

Published
2020
Full Text
View/download PDF

25. Extended investigations of isotope effects on ECRH plasma in LHD

Author

Tanaka, K, Nakata, Misato, Ohtani, Yoshiaki, Tokuzawa, T, Yamada, Hirokazu, Warmer, F, Nunami, M, Satake, Shinichi, Tala, T, Tsujimura, T, and Takemura, Y

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

Isotope effects of ECRH plasma in LHD were investigated in detail. A clear difference of transport and turbulence characteristics in H and D plasmas was found in the core region, with normalized radius ρ < 0.8 in high collisionality regime. On the other hand, differences of transport and turbulence were relatively small in low collisionality regime. Power balance analysis and neoclassical calculation showed a reduction of the anomalous contribution to electron and ion transport in D plasma compared with H plasma in the high collisionality regime. In core region, density modulation experiments also showed more reduced particle diffusion in D plasma than in H plasma, in the high collisionality regime. Ion scale turbulence was clearly reduced at ρ < 0.8 in high collisionality regime in D plasma compared with H plasma. The gyrokinetic linear analyses showed that the dominant instability ρ = 0.5 and 0.8 were ion temperature gradient mode (ITG). The linear growth rate of ITG was reduced in D plasma than in H plasma in high collisionality regime. This is due to the lower normalized ITG and density gradient. More hollowed density profile in D plasma is likely to be the key control parameter. Present analyses suggest that anomalous process play a role to make hollower density profiles in D plasma rather than neoclassical process. Electron scale turbulence were also investigated from the measurements and linear gyrokinetic simulations.

Published
2020

30. Electron density profile measurements on LHD

Author

Kawahata, K., Tanaka, K., Tokuzawa, T., Ito, Y., Akiyama, T., Sanin, A., Okajima, S., Tsuji-Iio, S., and Vyacheslavov, L.

Subjects
Plasma dynamics -- Research, Business, Chemistry, Electronics, Electronics and electrical industries
Abstract

Several kinds of density diagnostics have been developed and routinely operated to provide density profile information on the large helical device. A 13-channel far-infrared laser interferometer and a two-color millimeter-wave interferometer are used for monitoring the density profile. A C[O.sub.2] laser imaging interferometer has been developed for detailed profiled measurements of density and density fluctuations. A C[O.sub.2] laser densitometer measuring the Faraday rotation was developed for the long-pulse operations of large helical device. Details of each diagnostics and sample results are presented. Index Terms--Helical plasma, interferometer, plasma, plasma diagnostics, polarimeter.

Published
2004

31. Long-pulse Plasma Discharges by Upgraded ECH System in the LHD

Author

Yoshimura Y., Kasahara H., Nagasaki K., Tokitani M., Ashikawa N., Ueda Y., Ito S., Kubo S., Shimozuma T., Igami H., Takahashi H., Nishiura M., Kobayashi S., Mizuno Y., Okada K., Ogasawara S., Makino R., Yamada I., Tokuzawa T., Tanaka K., Mutoh T., and Yamada H.

Subjects
Physics, QC1-999
Abstract

Until 2009, three high-power, over 1MW each, 77GHz gyrotrons have been installed and applied to the LHD experiment. In addition, a 154GHz gyrotron of 1MW was installed in 2012. The 77GHz gyrotrons suffer gradual increases of internal pressure during long-pulse operation delivering power to LHD. To mitigate the problem, quasi-steady operation by combination of on-off operations of the 77GHz gyrotrons was performed. Applying two 77GHz gyrotrons alternately with intervals of two minutes and an 84GHz gyrotron continuously, a 30 min. long-pulse discharge with the line average electron density ne_ave of 0.7×1019m−3 and the central electron temperature Te0 of 1.7keV was achieved by the time average injection power Pinj of 260kW in 2012, showing significant progress in sustained density from the former 65 min. discharge with ne_ave of 0.15×1019m−3 and Te0 of 1.7keV by Pinj of 110kW of 84GHz wave. In 2013, one of the 77GHz gyrotron was improved to furnish a sub-window to remove stray radiation inside the tube. And the new 154GHz gyrotron was applied to the long-pulse discharge experiment. Using three gyrotrons: 154, the improved and an existing 77GHz with Pinj of 340kW in total, higher temperature plasma having steep temperature gradient typical for internal transport barrier, with ne_ave of 1.1×1019m−3 and Te0 of 3.5keV was quite stably sustained for 325s.

Published
2015
Full Text
View/download PDF

32. Isotope effect in transient electron thermal transport property and its impact on the electron internal transport barrier formation in LHD

Author

Kobayashi, T., primary, Ida, K., additional, Tanaka, K., additional, Yoshinuma, M., additional, Tsujimura, T.Ii, additional, Inagaki, S., additional, Tokuzawa, T., additional, Tsuchiya, H., additional, Tamura, N., additional, Igami, H., additional, Yoshimura, Y., additional, Itoh, S.-I., additional, Itoh, K., additional, and Experiment Group, LHD, additional

Published
2020
Full Text
View/download PDF

35. Isotope effects on energy, particle transport and turbulence in electron cyclotron resonant heating plasma of the Large Helical Device

Author

Tanaka, K., primary, Ohtani, Y., additional, Nakata, M., additional, Warmer, F., additional, Tsujimura, T., additional, Takemura, Y., additional, Kinoshita, T., additional, Takahashi, H., additional, Yokoyama, M., additional, Seki, R., additional, Igami, H., additional, Yoshimura, Y., additional, Kubo, S., additional, Shimozuma, T., additional, Tokuzawa, T., additional, Akiyama, T., additional, Yamada, I., additional, Yasuhara, R., additional, Funaba, H., additional, Yoshinuma, M., additional, Ida, K., additional, Goto, M., additional, Motojima, G., additional, Shoji, M., additional, Masuzaki, S., additional, Michael, C.A., additional, Vacheslavov, L.N., additional, Osakabe, M., additional, and Morisaki, T., additional

Published
2019
Full Text
View/download PDF

39. W-band millimeter-wave back-scattering system for high wavenumber turbulence measurements in LHD.

Author

Tokuzawa, T., Tanaka, K., Tsujimura, T., Kubo, S., Emoto, M., Inagaki, S., Ida, K., Yoshinuma, M., Watanabe, K. Y., Tsuchiya, H., Ejiri, A., Saito, T., and Yamamoto, K.

Subjects
*HETERODYNE detection, *TURBULENCE, *ANTENNAS (Electronics), *MEASUREMENT
Abstract

A 90 GHz W-band millimeter-wave back-scattering system is designed and installed for measuring electron scale turbulence (k⊥ρs ∼ 40). A metal lens relay antenna is used for in-vessel beam focusing, and a beam diameter of less than 40 mm is achieved in the plasma core region. This antenna can be steered at an angle of 159° ± 6°, which almost covers the plasma radius. The estimated size of the scattering volume is ∼105 mm at the edge and 135 mm at the core, respectively. A 60 m corrugated waveguide is used to achieve a low transmission loss of ∼8 dB. A heterodyne detection system for millimeter-wave circuits with probing power modulation can distinguish the scattered signal from background noise. [ABSTRACT FROM AUTHOR]

Published
2021
Full Text
View/download PDF

40. Summary of the 8th Asia-Pacific Transport Working Group (APTWG) Meeting

Author

Shi, Z.B., primary, Cheng, J., additional, Xu, Y.H., additional, Tokuzawa, T., additional, Qiu, Z.Y., additional, Sasaki, M., additional, Zhong, W.L., additional, Ida, K., additional, Wang, Z.X., additional, Zhang, T., additional, Kim, J., additional, Kwon, J.M., additional, Kobayashi, T., additional, and Lee, W.C., additional

Published
2019
Full Text
View/download PDF

43. Improved performance of electron cyclotron resonance heating by perpendicular injection in the Large Helical Device.

Author

Tsujimura, T.I., Yanai, R., Mizuno, Y., Tanaka, K., Yoshimura, Y., Tokuzawa, T., Nishiura, M., Sakamoto, R., Motojima, G., Kubo, S., Shimozuma, T., Igami, H., Takahashi, H., Yoshinuma, M., Ohshima, S., and Group, The LHD Experiment

Subjects
CYCLOTRON resonance, ELECTRON cyclotron resonance heating, ELECTRON density, CYCLOTRONS
Abstract

A real-time interlock system for power injection in electron cyclotron resonance heating (ECRH) was developed to be applied to Large Helical Device (LHD) plasma. This system enabled perpendicular injection, thus improving the performance of ECRH more than has ever been achieved before in LHD. Perpendicular propagation of the electron cyclotron wave at 77 GHz became more insensitive to the effect of refraction in comparison to the conventional oblique propagation. The achieved central electron temperature in the case of perpendicular injection was approximately 2 keV higher than that in the case of standard oblique injection for a central electron density of 1 × 1019 m−3 by 1 MW injection. With such improved performance of ECRH, high-density ECRH plasma of 8 × 1019 m−3 was successfully sustained after the injection of multiple hydrogen ice pellets for the first time in LHD. [ABSTRACT FROM AUTHOR]

Published
2021
Full Text
View/download PDF

46. Review of initial experimental results of the PSI studies in the large helical device

Author

Masuzaki, S, Akaishi, K, Funaba, H, Goto, M, Ida, K, Inagaki, S, Inoue, N, Kawahata, K, Komori, A, Kubota, Y, Morisaki, T, Morita, S, Nakamura, Y, Narihara, K, Nishimura, K, Noda, N, Ohyabu, N, Peterson, B.J, Sagara, A, Sakamoto, R, Sato, K, Shoji, M, Suzuki, H, Takeiri, Y, Tanaka, K, Tokuzawa, T, Watanabe, T, Tsuzuki, K, Hino, T, Matsumoto, Y, Kado, S, and Motojima, O

Published
2001
Full Text
View/download PDF

47. The effect of divertor tile material on radiation profiles in LHD

Author

Peterson, B.J., Masuzaki, S., Sakamoto, R., Sato, K., Inagaki, S., Sagara, A., Ohdachi, S., Nakamura, Y., Noda, N., Xu, Y., Rice, J.E., Ashikawa, N., Yamamoto, S., Takechi, M., Toi, K., Morita, S., Goto, M., Narihara, K., Inoue, N., Takeiri, Y., Sato, M., Osakabe, M., Tanaka, K., Tokuzawa, T., Sakakibara, S., Shoji, M., Kawahata, K., Kaneko, O., Ohyabu, N., Yamada, H., Komori, A., Yamazaki, K., Sudo, S., and Motojima, O.

Published
2001
Full Text
View/download PDF

48. Spatial structure of low-frequency fluctuations throughout the transition of poloidal flow velocity in edge plasmas of LHD.

Author

Moon, C., Kobayashi, T., Ida, K., Tokuzawa, T., Hidalgo, C., Yoshinuma, M., Ogawa, K., Itoh, K., and Fujisawa, A.

Subjects
TRANSITION flow, FLOW velocity, PLASMA devices, PLASMA boundary layers, POLOIDAL magnetic fields
Abstract

It is observed that a low-frequency (∼2 kHz) density fluctuation is excited in a transition of the poloidal flow velocity (Vθ) in the edge magnetic stochastic region of the Large Helical Device plasmas. Furthermore, it is found that the propagation velocity becomes approximately zero in the proximity of the appearance region of the low-frequency fluctuation by using the edge multichannel microwave Doppler reflectometer system. In particular, the low-frequency fluctuation is considered to be transmitted in both directions (inward and outward) away from the excitation position of the fluctuation, which behaves as the precursor of a magnetic fluctuation burst. Afterward, the edge H α signal intensity is sharply increased. [ABSTRACT FROM AUTHOR]

Published
2019
Full Text
View/download PDF

50. Development and application of radar reflectometer using micro to infrared waves

Author

Mase, A., primary, Kogi, Y., additional, Kuwahara, D., additional, Nagayama, Y., additional, Ito, N., additional, Maruyama, T., additional, Ikezi, H., additional, Wang, X., additional, Inutake, M., additional, Tokuzawa, T., additional, Kohagura, J., additional, Yoshikawa, M., additional, Shinohara, S., additional, Suzuki, A., additional, Sakai, F., additional, Yamashika, M., additional, Tobias, B. J., additional, Muscatello, C., additional, Ren, X., additional, Chen, M., additional, Domier, C. W., additional, and Luhmann, N. C., additional

Published
2018
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results