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Watanabe, Tamaki*; Toyama, Takeshi*; Hanamura, Kotoku*; Imao, Hiroshi*; Kamigaito, Osamu*; Kamoshida, Atsushi*; Kawachi, Toshihiko*; Koyama, Ryo*; Sakamoto, Naruhiko*; Fukunishi, Nobuhisa*; et al.
Proceedings of 16th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.1105 - 1108, 2019/07
Upgrades for the RIKEN heavy-ion linac (RILAC) involving a new superconducting linac (SRILAC) are currently underway at the RIKEN radioactive isotope beam factory (RIBF). It is crucially important to develop nondestructive beam measurement diagnostics. We have developed a beam energy position monitor (BEPM) system which can measure not only the beam position but also the beam energy simultaneously by measuring the time of flight of the beam. We fabricated 11 BEPMs and completed the position calibration to obtain the sensitivity and offset for each BEPMs. The position accuracy has been achieved to be less than 
0.1 mm by using the mapping measurement.
Watanabe, Tamaki*; Imao, Hiroshi*; Kamigaito, Osamu*; Sakamoto, Naruhiko*; Fukunishi, Nobuhisa*; Fujimaki, Masaki*; Yamada, Kazunari*; Watanabe, Yutaka*; Koyama, Ryo*; Toyama, Takeshi*; et al.
Proceedings of 15th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.49 - 54, 2018/08
no abstracts in English
Ishizawa, Akihiro*; Idomura, Yasuhiro; Imadera, Kenji*; Kasuya, Naohiro*; Kanno, Ryutaro*; Satake, Shinsuke*; Tatsuno, Tomoya*; Nakata, Motoki*; Nunami, Masanori*; Maeyama, Shinya*; et al.
Purazuma, Kaku Yugo Gakkai-Shi, 92(3), p.157 - 210, 2016/03
The high-performance computer system Helios which is located at The Computational Simulation Centre (CSC) in The International Fusion Energy Research Centre (IFERC) started its operation in January 2012 under the Broader Approach (BA) agreement between Japan and the EU. The Helios system has been used for magnetised fusion related simulation studies in the EU and Japan and has kept high average usage rate. As a result, the Helios system has contributed to many research products in a wide range of research areas from core plasma physics to reactor material and reactor engineering. This project review gives a short catalogue of domestic simulation research projects. First, we outline the IFERC-CSC project. After that, shown are objectives of the research projects, numerical schemes used in simulation codes, obtained results and necessary computations in future.
C level structure by 
-ray spectroscopyHosomi, Kenji; Ma, Y.*; Ajimura, Shuhei*; Aoki, Kanae*; Dairaku, Seishi*; Fu, Y.*; Fujioka, Hiroyuki*; Futatsukawa, Kenta*; Imoto, Wataru*; Kakiguchi, Yutaka*; et al.
Progress of Theoretical and Experimental Physics (Internet), 2015(8), p.081D01_1 - 081D01_8, 2015/08
Times Cited Count：14 Percentile：66.39(Physics, Multidisciplinary)Level structure of the C hypernucleus was precisely determined by means of -ray spectroscopy. We identified four -ray transitions via the 
C
reaction using a germanium detector array, Hyperball2. The spacing of the ground-state doublet 
was measured to be 
(stat)
(syst)keV from the direct 
transition. Excitation energies of the 
and 
states were measured to be 
, keV and 
, keV, respectively. The obtained level energies provide definitive references for the reaction spectroscopy of 
hypernuclei.
Nago, Makito*; Hagihara, Takeshi*; Minamide, Masashi*; Motoshima, Takayuki*; Jin, Kazumi; Kudo, Hajime; Sugita, Yutaka; Miura, Yoichi*
Dai-49-Kai Zenkoku Kensetsugyo Rodo Saigai Boshi Taikai Kenkyu Rombunshu (CD-ROM), p.77 - 80, 2012/10
This paper presents measures against gas emission during deep shaft excavation in the Horonobe Underground Research Laboratory Project (Horonobe URL Project). The gas control measures taken in the Horonobe URL Project include the following: (1) determination of the amount of methane contained in surrounding strata and groundwater, and gas concentration based on preliminary investigations, (2) determination of the specifications of fans, dust collectors, and ducts through ventilation network analysis (simulation), (3) reduction of methane gas emission through the use of waterproofing grout, (4) prohibition on the use of internal-combustion engine and the adoption of explosion-proof equipment, (5) development of methane gas control system, and (6) monitoring of methane gas emission. (3) to (6) described above are performed daily in the safety management activities and described in detail in this paper. The ventilation and eastern access shafts have currently reached a depth of 290 m and 250 m, respectively. The emission of methane gas has been observed to rise 0.3 % to 1.3 % in the fault zone, and it is controlled appropriately according to the gas control measures described above. As the measure to reduce the methane gas concentration, monitoring is confirmed to be effective.
KM1Okazaki, Nobuo; Tamada, Taro; Feese, M. D.*; Kato, Masaru*; Miura, Yutaka*; Komeda, Toshihiro*; Kobayashi, Kazuo*; Kondo, Keiji*; Blaber, M.*; Kuroki, Ryota
Protein Science, 21(4), p.539 - 552, 2012/04
Times Cited Count：3 Percentile：6.63(Biochemistry & Molecular Biology)Yamada, Hiroshi*; Takenaga, Hidenobu; Suzuki, Takahiro; Fujita, Takaaki; Takizuka, Tomonori; Kamada, Yutaka; Asakura, Nobuyuki; Tsuda, Takashi; Takechi, Manabu; Matsunaga, Go; et al.
Nuclear Fusion, 47(11), p.1418 - 1424, 2007/11
Times Cited Count：1 Percentile：3.5(Physics, Fluids & Plasmas)High densities exceeding the Greenwald limit by a factor of 1.7 have been obtained in discharges with high internal inductances of 
as high as 2.8 in JT-60U L-mode plasmas. The internal inductance, which is an index of the edge magnetic shear, is controlled by ramping down the plasma current. In addition to the extension of the operational regime, confinement performance remains as good as an H89PL factor of 1.5 even above the Greenwald limit. While the earlier work of a high study has indicated that core confinement improvement, the additional improvement of the tolerance against the high density is turned out to be correlated with high edge temperature. The normalized density when the detachment characterized by the decrease in a D
signal at the divertor occurs is even higher in the case with no disruption than the case with a disruption. These comparisons have indicated that the improvement in thermal and particle transport does exist in the periphery and the edge in the high plasmas, and mitigation of the density limit is observed coincidently. Although the high discharge studied here lies outside of the usual parameter space for a steady-state operation of tokamak, demonstration of a stable discharge with good confinement beyond the Greenwald limit suggest the magnetic shear at the edge is one key parameter to uncover physical element of the operational density limit.
Fujita, Takaaki; Tamai, Hiroshi; Matsukawa, Makoto; Kurita, Genichi; Bialek, J.*; Aiba, Nobuyuki; Tsuchiya, Katsuhiko; Sakurai, Shinji; Suzuki, Yutaka; Hamamatsu, Kiyotaka; et al.
Nuclear Fusion, 47(11), p.1512 - 1523, 2007/11
Times Cited Count：24 Percentile：63.17(Physics, Fluids & Plasmas)Design of modification of JT-60U, JT-60SA, has been optimized in viewpoint of plasma control, and operation regimes have been evaluated. Upper and lower divertors with different geometry are prepared for flexibility of plasma shape control. The beam lines of negative-ion NBI are shifted downward for off-axis current drive, in order to obtain a weak/reversed shear plasma. The feedback control coils along the port hole in the stabilizing plate are found effective to suppress the resistive wall mode (RWM) and sustain high 
close to the ideal wall limit. The regime of full current drive operation has been extended with upgraded heating and current drive power. Full current drive operation for 100 s with reactor-relevant high values of normalized beta and bootstrap current fraction (
= 2.4 MA, = 4.4, 
= 0.70, 
/
= 0.86, H
= 1.3) is expected in a highly-shaped low-aspect-ratio configuration (
= 2.65). High , high-density ELMy H-mode is also expected.
Tamai, Hiroshi; Fujita, Takaaki; Kikuchi, Mitsuru; Kizu, Kaname; Kurita, Genichi; Masaki, Kei; Matsukawa, Makoto; Miura, Yukitoshi; Sakurai, Shinji; Sukegawa, Atsuhiko; et al.
Fusion Engineering and Design, 82(5-14), p.541 - 547, 2007/10
Times Cited Count：9 Percentile：54.79(Nuclear Science & Technology)JT-60SA is positioned as the ITER satellite tokamak to conduct research elements to support and supplement ITER towards DEMO under the joint collaboration of Japan and EU. After the discussions in JA-EU Satellite Tokamak Working Group in 2005, the heating power is increased up to 41MW, 100s to ensure the ITER support research. With such increased heating power, the prospective plasma performances are analysed by the equilibrium and transport analysis codes. Operation window of a fully non-inductive current drive is extended to high density region. Simultaneous achievement of high equivalent Q
and high normalised beta is also expected in wide operational margin. Those prospects strongly indicate that JT-60SA is suitable machine to conduct the advanced research orienting to ITER and DEMO.
Shinohara, Koji; Sakurai, Shinji; Ishikawa, Masao; Tsuzuki, Kazuhiro*; Suzuki, Yutaka; Masaki, Kei; Naito, Osamu; Kurihara, Kenichi; Suzuki, Takahiro; Koide, Yoshihiko; et al.
Nuclear Fusion, 47(8), p.997 - 1004, 2007/08
Times Cited Count：40 Percentile：78.29(Physics, Fluids & Plasmas)Ferritic steel plates have been installed to improve the energetic ion confinement through reducing a toroidal magnetic field ripple. Aiming at cost-effective installation, orbit following calculations of energetic ions were performed for a design of ferritic installation on JT-60U by using the Fully three Dimensional magnetic field Orbit-Following Monte-Carlo (F3D OFMC) code. The installed ferritic steel adds the non-linear magnetic field on magnetic sensors for a plasma control and an equilibrium calculation. The code for a real-time control has been modified to take into account the magnetic field by ferritic steel. The plasma operation was successfully resumed and a real-time plasma control was successfully carried out after usual preparation processes. The heat load measurement indicates the improved confinement of energetic ions. These results are important for practical application of ferritic steel which is a leading candidate of a structural material on a demo reactor.
McDonald, D. C.*; Cordey, J. G.*; Thomsen, K.*; Kardaun, O. J. W. F.*; Snipes, J. A.*; Greenwald, M.*; Sugiyama, L.*; Ryter, F.*; Kus, A.*; Stober, J.*; et al.
Nuclear Fusion, 47(3), p.147 - 174, 2007/03
Times Cited Count：51 Percentile：29.82(Physics, Fluids & Plasmas)This paper describes the updates to and analysis of the International Tokamak Physics Activity (ITPA) Global H-node Confinement Database version 3 (DB3) over the period 1994-2004. Global data, for the energy confinement time and its controlling parameters, have now been collected from 18 machines of different sizes and shapes: ASDEX, ASDEX Upgrade, C-Mod CoMPASS-D, DIII-D, JET, JFT-2M, JT-60U, MAST, NSTX, PBX-M, PDX, START, T-10, TCV, TdeV, TFTR and TUMAN-3M. A wide range of physics studies has been performed on DB3 with particular progress made in the separation of core and edge behavior, dimensionless parameter analyses and the comparison of the database with one-dimensional transport code. A key aim of the database has always been to provide a basis for estimating the energy confinement properties of next step machines such as ITER, and so the impact of the database and its analysis on such machines is also discussed.
Shinohara, Koji; Sakurai, Shinji; Ishikawa, Masao; Tsuzuki, Kazuhiro*; Suzuki, Yutaka; Masaki, Kei; Naito, Osamu; Kurihara, Kenichi; Suzuki, Takahiro; Koide, Yoshihiko; et al.
Proceedings of 21st IAEA Fusion Energy Conference (FEC 2006) (CD-ROM), 8 Pages, 2007/03
Ferritic steel plates have been installed to improve the energetic ion confinement through reducing a toroidal magnetic field ripple. Aiming at cost-effective installation, orbit following calculations of energetic ions were performed for a design of ferritic installation on JT-60U by using the Fully three Dimensional magnetic field Orbit-Following Monte-Carlo (F3D OFMC) code. The installed ferritic steel adds the non-linear magnetic field on magnetic sensors for a plasma control and an equilibrium calculation. The code for a real-time control have been modified to take into account the magnetic field by ferritic steel. The plasma operation was successfully resumed and a real-time plasma control was successfully carried out after usual preparation processes. The heat load measurement indicates the improved confinement of energetic ions. These results are important for practical application of ferritic steel which is a leading candidate of a structural material on a demo reactor.
Yamada, Hiroshi*; Takenaga, Hidenobu; Suzuki, Takahiro; Fujita, Takaaki; Takizuka, Tomonori; Kamada, Yutaka; Asakura, Nobuyuki; Tsuda, Takashi; Takechi, Manabu; Matsunaga, Go; et al.
Proceedings of 21st IAEA Fusion Energy Conference (FEC 2006) (CD-ROM), 8 Pages, 2007/03
no abstracts in English
Ninomiya, Hiromasa; Akiba, Masato; Fujii, Tsuneyuki; Fujita, Takaaki; Fujiwara, Masami*; Hamamatsu, Kiyotaka; Hayashi, Nobuhiko; Hosogane, Nobuyuki; Ikeda, Yoshitaka; Inoue, Nobuyuki; et al.
Journal of the Korean Physical Society, 49, p.S428 - S432, 2006/12
To contribute DEMO and ITER, the design to modify the present JT-60U into superconducting coil machine, named National Centralized Tokamak (NCT), is being progressed under nationwide collaborations in Japan. Mission, design and strategy of this NCT program is summarized.
Takenaga, Hidenobu; Kubo, Hirotaka; Kamada, Yutaka; Miura, Yukitoshi; Kishimoto, Yasuaki; Ozeki, Takahisa
Fusion Science and Technology, 50(4), p.503 - 507, 2006/11
Times Cited Count：3 Percentile：24.08(Nuclear Science & Technology)no abstracts in English
-mode plasmas in JT-60U tokamakUrano, Hajime; Takizuka, Tomonori; Takenaga, Hidenobu; Oyama, Naoyuki; Miura, Yukitoshi; Kamada, Yutaka
Nuclear Fusion, 46(8), p.781 - 787, 2006/08
Times Cited Count：23 Percentile：58.7(Physics, Fluids & Plasmas)The degradation of energy confinement with increased toroidal beta 
was shown by the non-dimensional analysis in JT-60U. The dependence of the energy confinement on was examined by both the JT-60U ELMy 
-mode confinement database and the dedicated experiment on a single scan while 
and 
were kept fixed as well as the other magnetic geometrical parameters. In both cases, the degradation of energy confinement with increasing was observed, satisfying the relation of 
. This dependence is a little weaker than that predicted by the IPB98(y,2) scaling. The fusion power production rate was estimated to increase in proportion to 
.
Kaye, S. M.*; Valovic, M.*; Chudnovskiy, A.*; Cordey, J. G.*; McDonald, D.*; Meakins, A.*; Thomsen, K.*; Akers, R.*; Bracco, G.*; Brickley, C.*; et al.
Plasma Physics and Controlled Fusion, 48(5A), p.A429 - A438, 2006/05
Times Cited Count：15 Percentile：45.96(Physics, Fluids & Plasmas)The effects of aspect ratio and beta on confinement scaling are studied with the use of the H-mode database extended by the low aspect ratio data from NSTX and MAST. Various statistical methods are applied. Development of scalings using engineering parameters as predictor variables results in the inverse-aspect-ratio scaling with the range from 0.38 to 1.29. The transformation of these scalings to physics variables results in an unfavorouble dependence of the normalized energy confinement time on beta. There is a strong correlation between the inverse aspect ratio and beta, and this makes scalings based on physics variables imprecise.
Shinohara, Koji; Suzuki, Yutaka; Sakurai, Shinji; Masaki, Kei; Fujita, Takaaki; Miura, Yukitoshi
NIFS-PROC-63, p.158 - 162, 2006/04
For the further pursuit of the steady-state advanced tokamak research, the ferritic insertion was proposed to reduce the toroidal field (TF) ripple. The reduction of energetic ion loss due to the TF ripple reduction brings: (1) the enhancement of the heating and current drive "effective" efficiency, (2) the extended pulse length and the improved efficiency of RF injection due to the reduced heat flux on antennas and improved coupling between antennas and a plasma, (3) the availability of a wall stabilization without losing heating power, and (4) the possibility of an enhanced availability of the rotation control to improve the MHD stability and transport. The design work of ferritic inserts was carried out aiming at an effective, machine-safe, and short-term installation. Here, the design work for ferritic inserts is described from the viewpoint of the behavior of energetic ions. The confinement of energetic ions and the absence of the unfavorable heat flux on the first wall was assessed by using the Fully three Dimensional magnetic field OFMC code, which was developed for a ferrite insert program in JFT-2M. In the final design, the confinement of energetic ions is improved by about 1.3 times in a large volume plasma with Bt0 = 1.9T.
Kikuchi, Mitsuru; Tamai, Hiroshi; Matsukawa, Makoto; Fujita, Takaaki; Takase, Yuichi*; Sakurai, Shinji; Kizu, Kaname; Tsuchiya, Katsuhiko; Kurita, Genichi; Morioka, Atsuhiko; et al.
Nuclear Fusion, 46(3), p.S29 - S38, 2006/03
Times Cited Count：13 Percentile：41.68(Physics, Fluids & Plasmas)The National Centralized Tokamak (NCT) facility program is a domestic research program for advanced tokamak research to succeed JT-60U incorporating Japanese university accomplishments. The mission of NCT is to establish high beta steady-state operation for DEMO and to contribute to ITER. The machine flexibility and mobility is pursued in aspect ratio and shape controllability, feedback control of resistive wall modes, wide current and pressure profile control capability for the demonstration of the high-b steady state.
Tsuchiya, Katsuhiko; Akiba, Masato; Azechi, Hiroshi*; Fujii, Tsuneyuki; Fujita, Takaaki; Fujiwara, Masami*; Hamamatsu, Kiyotaka; Hashizume, Hidetoshi*; Hayashi, Nobuhiko; Horiike, Hiroshi*; et al.
Fusion Engineering and Design, 81(8-14), p.1599 - 1605, 2006/02
Times Cited Count：1 Percentile：9.94(Nuclear Science & Technology)no abstracts in English
