Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Ide, Shunsuke; Aiba, Nobuyuki; Bolzonella, T.*; Challis, C. D.*; Fujita, Takaaki; Giruzzi, G.*; Joffrin, E.*; Hamamatsu, Kiyotaka; Hayashi, Nobuhiko; Honda, Mitsuru; et al.
Proceedings of 24th IAEA Fusion Energy Conference (FEC 2012) (CD-ROM), 8 Pages, 2013/03
Ide, Shunsuke; Hayashi, Nobuhiko; Honda, Mitsuru; Urano, Hajime; Suzuki, Takahiro; Miyata, Yoshiaki; Aiba, Nobuyuki; Shiraishi, Junya; Kurita, Genichi; Fujita, Takaaki
Plasma and Fusion Research (Internet), 7(Sp.1), p.2403131_1 - 2403131_4, 2012/09
no abstracts in English
studied by means of NMR/NQR techniquesSakai, Hironori; Kurita, Nobuyuki*; Miclea, C. F.*; Movshovich, R.*; Lee, H.-O.*; Ronning, F.*; Bauer, E. D.*; Thompson, J. D.*
Journal of the Physical Society of Japan, 80(Suppl.A), p.SA059_1 - SA059_3, 2011/07
The effect of dilute La substitution in Ce
La
RhIn
(0
x0.07) has been investigated microscopically by nuclear magnetic/quadrupole resonance (NMR/NQR). By the dilute La substitutions, the 4
lines for In(1) sites are found to be undisturbed and to have a reasonably narrow width, even in the ordered AF state. These 4 positions in the La-substituted CeRhIn indicate a decrease of the internal field on In(1) sites, due to the reduction of hyperfine couplings by La substitutions. The spin-lattice relaxation rates (
) using these 4 lines at high temperatures can be understood by the reduction of exchange energy and effective moments. On the other hand, in the AF ordered state can be explained by a gapped Fermi surface and spin fluctuations of uncompensated localized Ce moments near the La ions.
collisions at 
= 200 GeVAdare, A.*; Afanasiev, S.*; Aidala, C.*; Ajitanand, N. N.*; Akiba, Y.*; Al-Bataineh, H.*; Alexander, J.*; Aoki, K.*; Aphecetche, L.*; Armendariz, R.*; et al.
Physical Review D, 84(1), p.012006_1 - 012006_18, 2011/07
Times Cited Count：28 Percentile：72.14(Astronomy & Astrophysics)We report on the event structure and double helicity asymmetry (
) of jet production in longitudinally polarized collisions at = 200 GeV. Photons and charged particles were measured by the PHENIX experiment. Event structure was compared with the results from PYTHIA event generator. The production rate of reconstructed jets is satisfactorily reproduced with the next-to-leading-order perturbative QCD calculation. We measured = -0.0014 
0.0037 at the lowest 
bin and -0.0181 0.0282 at the highest bin. The measured is compared with the predictions that assume various 
distributions.
collisions at = 200 and 62.4 GeVAdare, A.*; Afanasiev, S.*; Aidala, C.*; Ajitanand, N. N.*; Akiba, Yasuyuki*; Al-Bataineh, H.*; Alexander, J.*; Aoki, Kazuya*; Aphecetche, L.*; Armendariz, R.*; et al.
Physical Review C, 83(6), p.064903_1 - 064903_29, 2011/06
Times Cited Count：176 Percentile：99.44(Physics, Nuclear)Transverse momentum distributions and yields for 
, and 
in collisions at = 200 and 62.4 GeV at midrapidity are measured by the PHENIX experiment at the RHIC. We present the inverse slope parameter, mean transverse momentum, and yield per unit rapidity at each energy, and compare them to other measurements at different collisions. We also present the scaling properties such as 
and 
scaling and discuss the mechanism of the particle production in collisions. The measured spectra are compared to next-to-leading order perturbative QCD calculations.
and Au+Au collisions at 
= 200 GeVAdare, A.*; Afanasiev, S.*; Aidala, C.*; Ajitanand, N. N.*; Akiba, Yasuyuki*; Al-Bataineh, H.*; Alexander, J.*; Aoki, Kazuya*; Aphecetche, L.*; Aramaki, Y.*; et al.
Physical Review C, 83(4), p.044912_1 - 044912_16, 2011/04
Times Cited Count：7 Percentile：46.61(Physics, Nuclear)Measurements of electrons from the decay of open-heavy-flavor mesons have shown that the yields are suppressed in Au+Au collisions compared to expectations from binary-scaled collisions. Here we extend these studies to two particle correlations where one particle is an electron from the decay of a heavy flavor meson and the other is a charged hadron from either the decay of the heavy meson or from jet fragmentation. These measurements provide more detailed information about the interaction between heavy quarks and the quark-gluon matter. We find the away-side-jet shape and yield to be modified in Au+Au collisions compared to collisions.
+ collisions at = 200 GeV and scaling properties of hadron productionAdare, A.*; Afanasiev, S.*; Aidala, C.*; Ajitanand, N. N.*; Akiba, Y.*; Al-Bataineh, H.*; Alexander, J.*; Aoki, K.*; Aphecetche, L.*; Armendariz, R.*; et al.
Physical Review D, 83(5), p.052004_1 - 052004_26, 2011/03
Times Cited Count：169 Percentile：98.48(Astronomy & Astrophysics)The PHENIX experiment at RHIC has measured the invariant differential cross section for production of 
, 
, 
and 
mesons in collisions at = 200 GeV. The spectral shapes of all hadron transverse momentum distributions are well described by a Tsallis distribution functional form with only two parameters, 
and 
, determining the high 
and characterizing the low regions for the spectra, respectively. The integrated invariant cross sections calculated from the fitted distributions are found to be consistent with existing measurements and with statistical model predictions.
Tobita, Kenji; Nishio, Satoshi*; Enoeda, Mikio; Nakamura, Hirofumi; Hayashi, Takumi; Asakura, Nobuyuki; Uto, Hiroyasu; Tanigawa, Hiroyasu; Nishitani, Takeo; Isono, Takaaki; et al.
JAEA-Research 2010-019, 194 Pages, 2010/08
JAEA-Research-2010-019-01.pdf:48.47MBJAEA-Research-2010-019-02.pdf:19.4MB
This report describes the results of the conceptual design study of the SlimCS fusion DEMO reactor aiming at demonstrating fusion power production in a plant scale and allowing to assess the economic prospects of a fusion power plant. The design study has focused on a compact and low aspect ratio tokamak reactor concept with a reduced-sized central solenoid, which is novel compared with previous tokamak reactor concept such as SSTR (Steady State Tokamak Reactor). The reactor has the main parameters of a major radius of 5.5 m, aspect ratio of 2.6, elongation of 2.0, normalized beta of 4.3, fusion out put of 2.95 GW and average neutron wall load of 3 MW/m
. This report covers various aspects of design study including systemic design, physics design, torus configuration, blanket, superconducting magnet, maintenance and building, which were carried out increase the engineering feasibility of the concept.
Matsunaga, Go; Takechi, Manabu; Aiba, Nobuyuki; Kurita, Genichi; Sakamoto, Yoshiteru; Koide, Yoshihiko; Isayama, Akihiko; Suzuki, Takahiro; Fujita, Takaaki; Oyama, Naoyuki; et al.
Plasma and Fusion Research (Internet), 4, p.051_1 - 051_7, 2009/11
no abstracts in English
Tobita, Kenji; Nishio, Satoshi; Enoeda, Mikio; Kawashima, Hisato; Kurita, Genichi; Tanigawa, Hiroyasu; Nakamura, Hirofumi; Honda, Mitsuru; Saito, Ai*; Sato, Satoshi; et al.
Nuclear Fusion, 49(7), p.075029_1 - 075029_10, 2009/07
Times Cited Count：135 Percentile：97.83(Physics, Fluids & Plasmas)Recent design study on SlimCS focused mainly on the torus configuration including blanket, divertor, materials and maintenance scheme. For vertical stability of elongated plasma and high beta access, a sector-wide conducting shell is arranged in between replaceable and permanent blanket. The reactor adopts pressurized-water-cooled solid breeding blanket. Compared with the previous advanced concept with supercritical water, the design options satisfying tritium self-sufficiency are relatively scarce. Considered divertor technology and materials, an allowable heat load to the divertor plate should be 8 MW/m or lower, which can be a critical constraint for determining a handling power of DEMO (a combination of alpha heating power and external input power for current drive).
Matsukawa, Makoto; Kikuchi, Mitsuru; Fujii, Tsuneyuki; Fujita, Takaaki; Hayashi, Takao; Higashijima, Satoru; Hosogane, Nobuyuki; Ikeda, Yoshitaka; Ide, Shunsuke; Ishida, Shinichi; et al.
Fusion Engineering and Design, 83(7-9), p.795 - 803, 2008/12
Times Cited Count：17 Percentile：73.62(Nuclear Science & Technology)no abstracts in English
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：23 Percentile：62.62(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.
Aiba, Nobuyuki; Tokuda, Shinji; Takizuka, Tomonori; Kurita, Genichi; Ozeki, Takahisa
Nuclear Fusion, 47(4), p.297 - 304, 2007/04
Times Cited Count：14 Percentile：45.97(Physics, Fluids & Plasmas)Stability of a peeling, a ballooning, and a peeling-ballooning modes, which relate to edge-localized modes (ELMs), are investigated numerically with the linear ideal magnetohydrodynamic (MHD) stability code MARG2D. Effects of "sharpness" on the stability of the peeling-ballooning mode are examined, where the sharpness is defined in terms of the curvature at the top or bottom of the outermost flux surface. It is found that the stability limit of the pressure gradient significantly improves as the sharpness increases even when the ellipticity and the triangularity are unchanged. The sharpness is an important parameter for high performance H-mode operations with high pedestal pressure.
Aiba, Nobuyuki; Tokuda, Shinji; Takizuka, Tomonori; Kurita, Genichi; Ozeki, Takahisa
Proceedings of 21st IAEA Fusion Energy Conference (FEC 2006) (CD-ROM), 8 Pages, 2007/03
Stabilities of peeling, ballooning and peeling-ballooning modes, which relate to edge-localized modes (ELMs), are investigated numerically with the linear ideal magnetohydrodynamic (MHD) stability code MARG2D. Effects of "sharpness" on the stability of the peeling-ballooning mode are examined, where the sharpness is defined in terms of the curvature at the top and bottom of the outermost flux surface. It is found for the first time that the stable pressure gradient significantly improves as the sharpness increases even when the ellipticity and the triangularity are unchanged. The sharpness is an important parameter for high performance H-mode operations with high pedestal pressure.
Takechi, Manabu; Matsunaga, Go; Ozeki, Takahisa; Aiba, Nobuyuki; Kurita, Genichi; Isayama, Akihiko; Koide, Yoshihiko; Sakamoto, Yoshiteru; Fujita, Takaaki; Kamada, Yutaka; et al.
Proceedings of 21st IAEA Fusion Energy Conference (FEC 2006) (CD-ROM), 8 Pages, 2007/03
This is the first experimental result which demonstrates the dependence of critical RWM onset of plasma rotation and beta on initial plasma rotation with the variation of the angular momentum input and without magnetic braking. In the JT-60U with newly ferretic wall installed, it is possible to produce high beta plasma tightly coupled with the wall (b/a=1.2) above 
. In near-zero plasma rotation, the RWM started to grow at = and with finite plasma rotation, the plasma pressure survives up to much higher 
level than that with small rotation. The observed critical beta onset 
and the RWM growth rate 
are discussed along with theoretical predictions using experimentally observed q-, pressure-, and rotation profiles. The critical rotation of RWM on JT-60U is less one-second times lower than previous report of other tokamaks.
Takechi, Manabu; Matsunaga, Go; Aiba, Nobuyuki; Fujita, Takaaki; Ozeki, Takahisa; Koide, Yoshihiko; Sakamoto, Yoshiteru; Kurita, Genichi; Isayama, Akihiko; Kamada, Yutaka; et al.
Physical Review Letters, 98(5), p.055002_1 - 055002_4, 2007/02
Times Cited Count：119 Percentile：94.6(Physics, Multidisciplinary)The plasma rotation necessary for stabilization of resistive wall modes (RWMs) is investigated by controlling the toroidal plasma rotation with external momentum input by injection of tangential neutral beams. The observed threshold is 0.3 % of the Alfv
n velocity and much smaller than the previous experimental results obtained with magnetic braking. This low critical rotation has a very weak dependence as the ideal wall limit is approached. These results indicate that for large plasmas such as in future fusion reactors with low rotation, the requirement of the additional feedback control system for stabilizing RWM is much reduced.
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.
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：42.23(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：10.06(Nuclear Science & Technology)no abstracts in English
Matsunaga, Go; Takechi, Manabu; Kurita, Genichi; Sakamoto, Yoshiteru; Koide, Yoshihiko; Isayama, Akihiko; Suzuki, Takahiro; Fujita, Takaaki; Aiba, Nobuyuki; Ozeki, Takahisa; et al.
Europhysics Conference Abstracts (CD-ROM), 30I, 4 Pages, 2006/00
no abstracts in English
