Refereed papers
[1]K. Nagaoka, R. Nakamoto, T. Sasaki, T. Hamajima, H. Nakano, K. Ikeda, Y. Fujiwara, M. Osakabe, Y. Takeiri, K. Tsumori
Beam instability in the vicinity of beam extraction region of negative ion source
Journal of Physics: Conference Series22440120432022
[doi:10.1088/1742-6596/2244/1/012043]
OPEN ACCESS
[2]K. Nagaoka, H. Takahashi, M. Nakata, S. Satake, K. Tanaka, K. Mukai, M. Yokoyama, H. Nakano, S. Murakami, K. Ida, M. Yoshinuma, S. Ohdachi, T. Bando, M. Nunami, R. Seki, H. Yamaguchi, M. Osakabe, T. Morisaki, the LHD Experiment Group
Transport characteristics of deuterium and hydrogen plasmas with ion internal transport barrier in the Large Helical Device
Nuclear Fusion591060022019
[doi:10.1088/1741-4326/ab2d02]
[NIFS repository]
[3]K. Nagaoka, S. Hotta, Y. Hidaka, T. Kobayashi, K. Terasaka, S. Yoshimura
Characteristics of electroconvection turbulence and proposal of its application to turbulent transport experiment in a rotating spherical shell
High Energy Density Physics3179-822019
[doi:10.1016/j.hedp.2019.03.006]
[NIFS repository]
[4]K. Nagaoka, H. Takahashi, K. Tanaka, M. Osakabe, S. Murakami, S. Maeta, M. Yokoyama, K. Fujii, H. Nakano, H. Yamada, Y. Takeiri, K. Ida, M. Yoshinuma, the LHD experiment group
Comparison of Ion Internal Transport Barrier Formation between Hydrogen and Helium Dominated Plasmas
Plasma and Fusion Research1124021062016
[doi:10.1585/pfr.11.2402106]
[5]K. Nagaoka, H. Takahashi, S. Murakami, H. Nakano, Y. Takeiri, H. Tsuchiya, M. Osakabe, K. Ida, M. Yokoyama, M. Yoshinuma, S. Morita, M. Goto, T. Oishi, N. Pablant, K. Fujii, K. Tanaka, N. Tamura, Y. Nakamura, D. Xiaodi, T. Ido, A. Shimizu, S. Kubo, H. Igami, R. Seki, C. Suzuki, Y. Suzuki, K. Tsumori, K. Ikeda, M. Kisaki, Y. Yoshimura, T. Shimozuma, T. Seki, K. Saito, H. Kasahara, S. Kamio, T. Mutoh, O. Kaneko, H. Yamada, A. Komori
Integrated discharge scenario for high-temperature helical plasma in LHD
Nuclear Fusion551130202015
[doi:10.1088/0029-5515/55/11/113020]
[6]K. Nagaoka, T. Ido, E. Ascasibar, T. Estrada, S. Yamamoto, A. V. Melnikov, A. Cappa, C. Hidalgo, M. A. Pedrosa, B. Ph. vanMilligen, I. Pastor, M. Liniers, M. A. Ochando, A. Shimizu, L. G. Eliseev, S. Ohshima, K. Mukai, Y. Takeiri
Mitigation of NBI-driven Alfvén eigenmodes by electron cyclotron heating in the TJ-II stellarator
Nuclear Fusion53072004-1-072004-62013
[doi:10.1088/0029-5515/53/7/072004]
[7]K. Nagaoka, K. Ida, M. Yoshinuma, Y. Suzuki, K. Kamiya, S. Satake, K. Tanaka, M. Yokoyama, S. Murakami, M. Osakabe, H. Takahashi, R. Seki, C. Suzuki, Y. Narushima, H. Nakano, M. Kisaki, K. Ikeda, K. Tsumori, Y. Takeiri, O. Kaneko, H. Yamada, LHD Experiment Group
3-D effects on viscosity and generation of toroidal and poloidal flows in LHD
Physics of Plasmas20056116-1-056116-62013
[doi:10.1063/1.4807126]
[8]K. Nagaoka, K. Ida, M. Yoshinuma, Y. Takeiri, M. Yokoyama, S. Morita, K. Tanaka, T. Ido, A. Shimizu, N. Tamura, H. Funaba, S. Murakami, M. Goto, H. Takahashi, C. Suzuki, Y. Suzuki, K. Ikeda, M. Osakabe, K. Tsumori, H. Nakano, O. Kaneko, H. Yamada, LHD Experiment Group
Heat and Momentum Transport of Ion Internal Transport Barrier Plasmas on the Large Helical Device
Nuclear Fusion51083022-1-083022-72011
[doi:10.1088/0029-5515/51/8/083022]
[9]K. NAGAOKA, Y. TAKEIRI, S. MORITA, K. IDA, M. YOKOYAMA, M. YOSHINUMA, H. FUNABA, S. MURAKAMI, T. MINAMI, K. TANAKA, T. IDO, A. SHIMIZU, K. IKEDA, M. OSAKABE, K. TSUMORI, O. KANEKO, LHD Experiment Group
ION HEATING EXPERIMENTS AND IMPROVEMENT OF ION HEAT TRANSPORT IN LHD
Fusion Science and Technology5846-522010
[doi:10.13182/FST58-46]
[10]K. Nagaoka, Y. Takeiri, K. Ida, M. Yoshinuma, S. Morita, N. Tamura, T. Ido, A. Shimizu, K. Ikeda, M. Osakabe, K. Tsumori, H. Nakano, LHD experiment group
Parameter Regime of Ion Internal Transport Barrier Formation in the Large Helical Device
Plasma and Fusion Research5S2029-1-S2029-42010
[doi:10.1585/pfr.5.S202]
OPEN ACCESS
[11]Kenichi NAGAOKA, Shinji KOBAYASHI, Katsuyuki HOSAKA, Satoshi YAMAMOTO, Tohru MIZUUCHI, Masaki OSAKABE, Yasuhiko TAKEIRI, Kazunobu NAGASAKI, Hiroyuki OKADA, Katsumi KONDO, Kiyoshi HANATANI, Fumimichi SANO
Observation of Fast Ion Response to MHD Activities in Heliotron J
Journal of Plasma and Fusion Research SERIES81100-11032009
[12]Kenichi Nagaoka, 1 Kiyomasa Y. Watanabe, 1 Masaki Osakabe, 1 Yasuhiko Takeiri, 1 Takashi Minami, 1 Kazuo Toi, 1 Mitsutaka Isobe, 1 Masaki Nishiura, 1 Takafumi Ito, Kunihiro Ogawa
Fast Ion Measurement Using a Hybrid Directional Probe in the Large Helical Device
Review of Scientific Instruments7910E523-1-10E523-32008
[doi:10.1063/1.2955569]
[13]Kenichi Nagaoka, Mitsutaka Isobe, Masaki Osakabe, Kiyomasa Y. Watanabe, Yasuhiko Takeiri, CHS experimental group
A Phenomenological Probe Model of Fast Ion Measurement Using a Hybrid Directional Probe
Contributions to Plasma Physics48480-4842008
[doi:10.1002/ctpp.200810077]
[14]K. Nagaoka, M. Isobe, K. Toi, K. Goto, T. Ito, Y. Todo, M. Osakabe, S. Ohshima, A. Shimizu, A. Fujisawa, H. Nakano, Y. Takeiri, K. Y. Watanabe, T. Akiyama, Y. Yoshimura, C. Suzuki, S. Nishimura, K. Matsuoka, S. Okamura, the CHS experimental group
Local observations of fast ion responses to energetic particle modes using a directional probe in the Compact Helical System (CHS)
Nuclear Fusion48084005-1-084005-92008
[doi:10.1088/0029-5515/48/8/084005]
[15]Kenichi NAGAOKA, Masayuki YOKOYAMA, Yasuhiko TAKEIRI, Katsumi IDA, Mikiro YOSHINUMA, Seikichi MATSUOKA, Hisamichi FUNABA, Shigeru MORITA, Takashi MUTOH, Tetsuo SEKI, Katsunori IKEDA, Masaki OSAKABE, Katsuyoshi TSUMORI, Yoshihide OKA, Osamu KANEKO, the LHD Experimental Group
Ion Heating Experiments Using Perpendicular Neutral Beam Injection in the Large Helical Device
Plasma and Fusion Research3S1013-1-S1013-52008
[doi:10.1585/pfr.3.S1013]
OPEN ACCESS
[16]Kenichi Nagaoka, Mitsutaka Isobe, Masaki Osakabe, Kiyomasa Y. Watanabe, Yasuhiko Takeiri, CHS experimental group
A PHENOMENOLOGICAL PROBE MODEL OF FAST ION MEASUREMENT USING A HYBRID DIRECTIONAL PROBE
Contributions to Plasma Physics48480-4842008
[doi:10.1002/ctpp.200810077]
[17]Kenichi Nagaoka, Mitsutaka Isobe, Kazuo Toi, Akihiro Shimizu, Akihide Fujisawa, Shinsuke Ohshima, Haruhisa Nakano, Masaki Osakabe, Yasushi Todo, Tsuyoshi Akiyama, Yoshihiko Nagashima, Chihiro Suzuki, Shin Nishimura, Yasuo Yoshimura, Keisuke Matsuoka, Shoichi Okamura
Radial Transport Characteristics of Fast Ions Due to Energetic-Particle Modes inside the Last Closed-Flux Surface in the Compact Helical System
Physical Review Letters100065005-1-065005-42008
[doi:10.1103/PhysRevLett100.065005]
[NIFS repository]
[18]Kenichi Nagaoka, Katsunori Ikeda, Masaki Osakabe, Yasuhiko Takeiri, Yoshihide Oka, Katsuyoshi Tsumori, Osamu Kaneko, LHD experimental group
Simultaneous Measurements of Proton Ratio and Beam Divergence of Positive-ion-based Neutral Beam in the Large Helical Device
Plasma and Fusion Research2S1051-1-S1051-32007
[doi:10.1585/pfr.2.S1051]
OPEN ACCESS
[19]Kenichi Nagaoka, Kiyomasa Watanabe, Katsumi Ida, Mikiro Yoshinuma, Takashi Kobuchi, Yoshiro Narushima, Kazuo Toi, Mitsutaka Isobe, Akihiro Shimizu, Takashi Minami, Tsuyoshi Akiyama, Keisuke Matsuoka, Shoichi Okamura, Katsunori Ikeda, Masaki Osakabe, Katsuyoshi Tsumori, Yoshihide Oka, Yasuhiko Takeiri, Osamu Kaneko
Z Dependence of Neutral Beam Driven Current in the Large Helical Device and the Compact Helical System
Journal of the Korean Physical Society4992-952006
[20]Kenichi NAGAOKA, Mitsutaka ISOBE, Kouji SHINOHARA, Masaki OSAKABE, Akihiro SHIMIZU, Shoichi OKAMURA
Energetic Ion Measurements Using a Directional Probe
Plasma and Fusion Research1005-1-005-22006
[doi:10.1585/pfr.1.005]
OPEN ACCESS
[21]Kenichi Nagaoka, 1 Atsushi Okamoto, 1 Shinji Yoshimura, 2 Mitsuo Kono, Masayoshi Y. Tanaka
Spontaneous Formation of a Plasma Hole in a Rotating Magnetized Plasma: A Giant Burgers Vortex in a Compressible Fluid
Physical Review Letters89075001-1-075001-42002
[doi:10.1103/PhysRevLett.89.075001]
[22]Kenichi Nagaoka, Atsushi Okamoto, Shinji Yoshimura, Masayoshi Y. Tanaka
Plasma Flow Measurement Using Directional Langmuir Probe Under Weakly Ion-Magnetized Conditions
Journal of the Physical Society of Japan70131-1372001
