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and 
cross sections of the 
C(
,
)
O reaction at 
1.2 MeV using pulsed beamsMakii, Hiroyuki; Ueda, Hitoshi*; Temma, Yasuyuki*; Nagai, Yasuki*; Shima, Tatsushi*; Fujimoto, Shinya*; Segawa, Mariko; Mishima, Kenji*; Nishiyama, Jun*; Igashira, Masayuki*
AIP Conference Proceedings 1269, p.283 - 288, 2010/10
Times Cited Count：0 Percentile：0.02(Astronomy & Astrophysics)The C(,)O reaction cross section plays an important role in stellar evolution at the stage of helium-burning. However, the cross section at low energy still has a large uncertainty mainly due to the poor determination of the ratio of cross section to one. Hence, we have installed new system to make a precise measurement of the cross section. In this experiment, we used the high efficiency anti-Compton NaI(Tl) spectrometers with a large S/N ratio, an intense pulsed beams, and the monitoring system of target thickness. With use of the system we succeeded in removing a background due to neutron and could clearly detect the -ray from the C(,)O reaction with high statistics. We determined the and cross section down to 
1.2 MeV, and thus obtained results are compared to recent theoretical calculations.
Oya, Kaoru*; Inai, Kensuke*; Kikuhara, Yasuyuki*; Nakano, Tomohide; Kawata, Jun*; Kawazome, Hayato*; Ueda, Yoshio*; Tanabe, Tetsuo*
Journal of Plasma and Fusion Research SERIES, Vol.8, p.419 - 424, 2009/09
Redeposition of C
H
and CH
chemically eroded from carbon walls is simulated by EDDY code incorporated with the reflection on a hydrogenated and amorphized carbon surface. The redeposition rate for heavy hydrocarbons is drastically decreased by introduction of the reflection. The redeposition patterns on the surface are enlarged by the reflection, but it is narrower for the heavy hydrocarbons than for CH. The photon emissions of C from CH (CH) decay faster than that of CH from CH in high-temperature (
10 eV) plasmas, which reproduces the difference of the decay of the CD and C light intensities observed in the vicinity of the outer diverter plates of JT-60U. For such temperatures, the inverse photon-efficiency, which is defined as the ratio of the number of the launching hydrocarbons to the photoemission events of CH and C, is in good agreement with the values observed in JT-60U experiments.
Tamai, Hiroshi; Matsukawa, Makoto; Kurita, Genichi; Hayashi, Nobuhiko; Urata, Kazuhiro*; Miura, Yushi; Kizu, Kaname; Tsuchiya, Katsuhiko; Morioka, Atsuhiko; Kudo, Yusuke; et al.
Plasma Science and Technology, 6(1), p.2141 - 2150, 2004/02
Times Cited Count：2 Percentile：6.49(Physics, Fluids & Plasmas)The dominant issue for the the modification program of JT-60 (JT-60SC) is to demonstrate the steady state reactor relevant plasma operation. Physics design on plasma parameters, operation scenarios, and the plasma control method are investigated for the achievement of high-
. Engineering design and the R&D on the superconducting magnet coils, radiation shield, and vacuum vessel are performed. Recent progress in such physics and technology developments is presented.
Ishida, Shinichi; Abe, Katsunori*; Ando, Akira*; Chujo, T.*; Fujii, Tsuneyuki; Fujita, Takaaki; Goto, Seiichi*; Hanada, Kazuaki*; Hatayama, Akiyoshi*; Hino, Tomoaki*; et al.
Nuclear Fusion, 43(7), p.606 - 613, 2003/07
no abstracts in English
Ishida, Shinichi; Abe, Katsunori*; Ando, Akira*; Cho, T.*; Fujii, Tsuneyuki; Fujita, Takaaki; Goto, Seiichi*; Hanada, Kazuaki*; Hatayama, Akiyoshi*; Hino, Tomoaki*; et al.
Nuclear Fusion, 43(7), p.606 - 613, 2003/07
Times Cited Count：33 Percentile：69.03(Physics, Fluids & Plasmas)no abstracts in English
Matsushima, Hidesuke*; Tsutsumi, Kiyoshi*; Kato, Yasuyoshi*; Urushihara, Hiroshi*; Ueda, Yasuyuki*
PNC TJ202 76-01, 151 Pages, 1976/05
PNC-TJ202-76-01.pdf:6.82MBPNC-TJ202-76-01VOL1.pdf:2.76MB
no abstracts in English
Segawa, Mariko; Nagai, Yasuki*; Masaki, Tomohiro*; Shima, Tatsushi*; Makii, Hiroyuki; Mishima, Kenji*; Ueda, Hitoshi*; Temma, Yasuyuki*; Igashira, Masayuki*; Osaki, Toshiro*; et al.
no journal, ,
no abstracts in English
Watanabe, Jun*; Fukumoto, Masakatsu*; Soga, Yasuyuki*; Otsuka, Yusuke*; Ueda, Yoshio*; Arai, Takashi; Asakura, Nobuyuki; Nakano, Tomohide; Sato, Masayasu; Yagyu, Junichi; et al.
no journal, ,
Tungsten was mainly deposited on the inner divertor (around the inner strike point) and the outer wing of the dome. Tungsten deposition on the dome was found only near the top surface (within depth of a few micron m), while tungsten on the inner divertor was codeposited with carbon to the depth up to about 60 micron m. Discussion on the relation between depth distribution of tungsten and EDX signals are also presented. Significant difference between tungsten and other metallic materials (Fe, Ni, Cr) in terms of toroidal deposition distribution on the outer wing was observed. Tungsten deposition was toroidally localized in the P-8 section, where tungsten coated tiles were installed. On the other hand, other metallic materials (Fe, Ni, Cr) were not toroidally localized compared with the case of tungsten.
Watanabe, Jun*; Fukumoto, Masakatsu*; Soga, Yasuyuki*; Otsuka, Yusuke*; Ueda, Yoshio*; Asakura, Nobuyuki; Arai, Takashi; Nakano, Tomohide; Sato, Masayasu; Yagyu, Junichi; et al.
no journal, ,
no abstracts in English
Segawa, Mariko; Nagai, Yasuki*; Masaki, Tomohiro*; Temma, Yasuyuki*; Shima, Tatsushi*; Makii, Hiroyuki*; Mishima, Kenji*; Ueda, Hitoshi*; Nakayoshi, Akira*; Ota, Takeshi*; et al.
no journal, ,
Re-Os pair is known as the most promising nuclear cosmochronometer with considerable potential. However, there remains non-trivial problems related to an excited neutron capture reaction of Os at a stellar temperature. Firstly, Os is produced and depleted by the slow process nucleosynthesis. Hence, it is necessary to obtain both the production and depletion rates of Os. Secondly, Os is depleted not only by its ground state neutron capture reaction but also by an excited state neutron capture reaction of Os in a stellar temperature. In the present study, we have measured the neutron capture reaction cross sections for 
Os, Os and 
Os accurately and neutron inelastic scattering reaction cross section for Os off the ground state of Os to its 9.75-keV first excited statein the neutron energy range from 10 to 100 keV. The measurements of the neutron capture reactions have been carried out by detecting a prompt -ray by means fan anti-Compton NaI(Tl) spectrometer. The (n, n') reaction cross section for Os has been measured with use of four 
Li-glass scintillation detectors. Based on these new capture cross sections, we reestimate on the basis of a careful reaction cross section calculation the correction factor F for the neutron capture on the 9.75-keV first excited state in Os as a function of stellar temperature, as required to derive the age of the galaxy within the Re-Os chronology.
Koizumi, Satoshi; Putra, A.; Zhao, Y.; Noda, Yohei; Yamaguchi, Daisuke; Ueda, Satoru*; Gunji, Hiroyuki*; Eguchi, Mika*; Tsutsumi, Yasuyuki*
no journal, ,
In order to investigate water history during fuel cell operation, we employed deuterated gas (D) as a fuel (deuterium fuel cell). With exchange of H and D, we aim to perform a contrast variation as for polyelectrolyte film (Nafion). When D gas is used as a fuel, DO is produced at the cathode and diffuses back to the film. Then the film, originally swollen by HO, exhibits change of coherent scattering contrast. By changing a fuel gas from H to D, SANS quantitatively detected decrease of scattering intensity at scattering maximum originating from the ion-channel in the electrolyte. After quantitative analyses on scattering intensity, which is related to water ratio (HO/DO) in the ion channel, we could determine the water ration swelling a membrane.
C(,)O reaction at E
= 1.2 and 1.5 MeV using pulsed beamMakii, Hiroyuki; Ueda, Hitoshi*; Nagai, Yasuki*; Segawa, Mariko; Temma, Yasuyuki*; Shima, Tatsushi*; Mishima, Kenji*; Igashira, Masayuki*
no journal, ,
The C(,)O reaction plays an important role in stellar evolution at the stage of He-burning. However the cross section at the stellar temperature still has a large uncertainty mainly due to the poor determination of the cross section ratio, 
. In order to make a precise measurement of the , we have installed a new measurement system of the -ray angular distributions of the C(,)O reaction. In this experiment, we used high efficiency anti-Compton NaI(Tl) spectrometers to detect -rays from the reaction with a large S/N ratio, an intense pulsed beams, and the monitoring system of the target thickness. With use of the system we succeeded in removing a background due to neutrons and could clearly detect the -ray from the reaction with high statistics. We determined the E1 and E2 cross section down to E = 1.2 MeV, and thus obtained results are compared to recent theoretical calculations.
