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Hamada, Kazuya; Takahashi, Yoshikazu; Nabara, Yoshihiro; Kawano, Katsumi; Ebisawa, Noboru; Oshikiri, Masayuki; Tsutsumi, Fumiaki; Saito, Toru*; Nakajima, Hideo; Matsuda, Hidemitsu*; et al.
Teion Kogaku, 47(3), p.153 - 159, 2012/03
The Japan Atomic Energy Agency (JAEA) has the responsibility to procure 25% of the ITER Toroidal Field coil conductors as the Japanese Domestic Agency (JADA) in the ITER project. The TF conductor is a circular shaped, cable-in-conduit conductor, composed of a cable and a stainless steel conduit (jacket). The outer diameter and maximum length of the TF conductor are 43.7 mm and 760 m, respectively. JAEA has constructed newly conductor manufacturing facility. Prior to starting conductor, JAEA manufactured a 760-m long Cu dummy conductor as process qualification of dummy cable, the jacket sections and fabrication procedures, such as welding, cable insertion, compaction and spooling. Following qualification of all manufacturing processes, JAEA has started to fabricate superconducting conductors for the TF coils.
Maruyama, Ryuji; Yamazaki, Dai; Ebisawa, Toru*; Hino, Masahiro*; Soyama, Kazuhiko
Thin Solid Films, 515(14), p.5704 - 5706, 2007/05
Times Cited Count:43 Percentile:81.58(Materials Science, Multidisciplinary)The development of neutron supermirrors is important for neutron scattering experiments since it offers a considerable increase in the available neutron intensity. Up to now, many studies have been carried out to realize high reflectivity and large , where is the ratio of the effective critical angle of the supermirror to that of natural nickel. We have developed neutron supermirrors by employing the ion beam sputtering (IBS) technique because it enables the production of layers with high density and small grain size. Although the IBS technique produces high quality layers, its disadvantage is that the deposition area is relatively small. In order to produce the optical devices using supermirrors, which is planned in the project of a new spallation neutron source (Japan Proton Accelerator Research Complex, J-PARC), a new IBS instrument with a large deposition area whose diameter is 500 mm has been designed and installed at the Japan Atomic Energy Agency. The deposition rate has been confirmed to be almost uniform over the entire deposition area. We have carried out the development of Ni/Ti supermirror with large . In this presentation, the performance of those supermirrors fabricated with the IBS instrument is discussed.
Yamazaki, Dai; Moriai, Atsushi; Tamura, Itaru; Maruyama, Ryuji; Ebisawa, Toru*; Takeda, Masayasu; Soyama, Kazuhiko
JAEA-Technology 2007-030, 21 Pages, 2007/03
A new neutron reflectometer "SUIREN" has been developed and started its operation at the research reactor JRR-3 of JAEA in 2006. SUIREN (Apparatus for Surface and Interface investigations with Reflection of Neutrons) provides monochromatic neutron beam with wavelength of 3.8 and vertical sample geometry, which is suitable for studies on interfaces involving solid layers of soft materials, magnetic materials, neutron mirrors and many other things. Collimated neutron intensity is about 2.110 2.610 n/s/cm with =0.08 deg at the sample position. Background is as low as 4.510 n/s when a local beam shutter is closed. A demonstration experiment showed that specular reflectivity of a silicon substrate of 3 inches in diameter can be measured down to 10 over 0 Qz 0.22 in 27 hours. This paper describes the beam-line and components of the SUIREN reflectometer, some results of test measurements and future plans.
Maruyama, Ryuji; Yamazaki, Dai; Ebisawa, Toru*; Hino, Masahiro*; Soyama, Kazuhiko
Physica B; Condensed Matter, 385-386(2), p.1256 - 1258, 2006/11
Times Cited Count:25 Percentile:70.29(Physics, Condensed Matter)Neutron supermirror has become an important device to transport, bending and focusing a neutron beam. We have developed it using ion beam sputtering (IBS) instrument since it enables us to produce good quality layers with high density and small grain size. We have also investigated ion-polishing technique, which suppresses the interface roughness of multilayers. We have now installed new IBS instrument with effective deposit area of 500 mm in diameter for the realization of supermirror guide and bender with large effective critical angle. In this presentation, the performance of the supermirrors fabricated with it and the future development of neutron optical devices using supermirrors will be discussed.
Yamazaki, Dai; Soyama, Kazuhiko; Ebisawa, Toru*; Takeda, Masayasu; Maruyama, Ryuji*; Tasaki, Seiji*
Physica B; Condensed Matter, 356(1-4), p.174 - 177, 2005/02
Times Cited Count:1 Percentile:6.20(Physics, Condensed Matter)Drabkin energy filter could be used as a fast chopper for pulsed neutrons by varying the resonant wavelength fast in such a way that resonant wavelength matches neutron wavelength at a small time region. The faster are varied, the smaller time window we could obtain. Neutron pulses could be sharpened much more effectively for a small wavelength band than in the wide-band pulse-shaping mode in which is varied in synchronization with the time-of-flight from the moderator. In our preliminary test of a chopper-mode with a prototype Drabkin energy filter, time-window of 0.21 ms was obtained while it was 1.08 ms with the filter driven stationary. Narrower time-window could have been obtained if we had more beam-time and it could be also narrowed with higher-resolution Drabkin filters.
Yamazaki, Dai; Soyama, Kazuhiko; Ebisawa, Toru*; Takeda, Masayasu; Torikai, Naoya*; Tasaki, Seiji*; Matsuoka, Hideki*
Physica B; Condensed Matter, 356(1-4), p.229 - 233, 2005/02
Times Cited Count:1 Percentile:6.20(Physics, Condensed Matter)The application of neutron reflectometry to study dynamic phenomena at surface and interfaces have been restricted so far. It was mainly due to the low intensity of neutron sources, but now high-intensity spallation neutron sources are under construction in Japan (J-PARC) and U.S. (SNS). We have a plan to install a spin-echo option on the J-PARC neutron reflectometer with horizontal sample geometry for studies on dynamics of surfaces and interfaces. This option is based on the resonance spin-echo method and aimed at dynamics upto hundreds of nanoseconds. In this contribution, the plan and status of development are introduced together with the principle and characteristics of this option.
Yamazaki, Dai; Ebisawa, Toru*
Hamon, 15(1), p.51 - 54, 2005/01
Neutron spin handling could be used for beam control and spectroscopy. Energy analysis could be performed with Drabkin energy filters, by which inelastic component with a , a or a could be extracted for all incident wavelength. Pulsed spin-flipper and polarization analyzer could be used as a neutron chopper (spin-flip chopper) whose opening time, number of windows and phase are controlled independently. It was demonstrated that S/N ratio can be enhanced up to 1.5 10 by installing three spin-flip choppers in sequence.
Maruyama, Ryuji*; Tasaki, Seiji*; Hino, Masahiro*; Takeda, Masayasu; Ebisawa, Toru*; Kawabata, Yuji*
Nuclear Instruments and Methods in Physics Research A, 530(3), p.505 - 512, 2004/09
Times Cited Count:10 Percentile:55.55(Instruments & Instrumentation)Neutron resonance spin echo (NRSE) spectroscopy enables us to measure neutron quasielastic scattering with high energy resolution. It is desirable to apply NRSE spectroscopy to pulsed neutron sources because this application allows a very wide range of the spin echo time. We have already developed the neutron resonance spin flipper applicable to a polychromatic pulsed neutron beam, which is necessary for the TOF-NRSE method. Using this flipper, we have succeeded in observing spin echo signals with visibility higher than 0.65 for the pulsed neutron beam with wavelength from 0.3 to 0.9 nm. We discuss the prospect of the NRSE spectrometer with high energy resolution on the basis of the present result.
Oku, Takayuki*; Sakai, Kenji*; Adachi, Tomohiro*; Ikeda, Kazuaki*; Shimizu, Hirohiko*; Maruyama, Ryuji*; Hino, Masahiro*; Tasaki, Seiji*; Kiyanagi, Yoshiaki*; Kamiyama, Takashi*; et al.
Physica B; Condensed Matter, 335(1-4), p.226 - 229, 2003/07
Times Cited Count:7 Percentile:39.28(Physics, Condensed Matter)no abstracts in English
Yamazaki, Dai; Soyama, Kazuhiko; Ebisawa, Toru*; Tamura, Itaru; Tasaki, Seiji*
Proceedings of ICANS-XVI, Volume 1, p.407 - 415, 2003/06
Drabkin energy filters extract neutrons of required wavelength using spatial neutron spin resonance. If they are applied to pulsed neutrons, they could sharpen pulse width and cut tail neutrons without reducing band-width or peak-intensity. Shaping of J-PARC coupled-moderator pulse by a Drabkin energy filter was simulated. In the simulation, discrete field gradient to Bx is introduced and total field B is varied in accordance with the dominant wavelength at each moment at the filter position. The results suggest that about 90 % or more of tail neutrons from coupled moderator are cut and a fliter with fields of 200 periods could reduce pulse width up to that of decoupled moderator. Effects of fluctuations of width of each half period were studied and it was found that fluctuation within 1 % are tolerable for a flipper with field of 100 or 200 periods.
Yamazaki, Dai; Soyama, Kazuhiko; Ebisawa, Toru*; Tasaki, Seiji*
JAERI-Research 2003-009, 29 Pages, 2003/03
no abstracts in English
Suzuki, Junichi; Tasaki, Seiji*; Soyama, Kazuhiko; Ebisawa, Toru*
Applied Physics A, 74(Suppl.1), p.S308 - S310, 2002/12
Times Cited Count:7 Percentile:31.68(Materials Science, Multidisciplinary)no abstracts in English
Maruyama, Ryuji; Yamazaki, Dai; Ebisawa, Toru*; Hino, Masahiro*; Soyama, Kazuhiko
no journal, ,
The development of high performance neutron supermirrors with high reflectivity and large , the ratio of the effective critical angle of the supermirror to that of natural nickel, is important for the J-PARC project since it greatly increases the available neutron intensity. Neutron supermirrors consist of alternating layers of two materials with different refractive indices for neutrons. An ion beam sputtering instrument with an effective deposition area of 0.2 m has been installed at the Japan Atomic Energy Agency in order to produce neutron guides, benders, and other neutron optical devices, which are planned for application in the J-PARC project. We have succeeded in fabricating the supermirror with large critical angle of and that with high reflectivity (85%) for .
Maruyama, Ryuji; Yamazaki, Dai; Ebisawa, Toru*; Soyama, Kazuhiko
no journal, ,
no abstracts in English
Yamazaki, Dai; Moriai, Atsushi; Maruyama, Ryuji; Tamura, Itaru; Ebisawa, Toru*; Soyama, Kazuhiko; Takeda, Masayasu; Hino, Masahiro*
no journal, ,
no abstracts in English
Maruyama, Ryuji; Yamazaki, Dai; Ebisawa, Toru*; Soyama, Kazuhiko
no journal, ,
The development of high performance neutron supermirrors with high reflectivity and large , the ratio of the effective critical angle of the supermirror to that of natural nickel, is important for the J-PARC project since it greatly increases the available neutron intensity. Neutron supermirrors consist of alternating layers of two materials with different refractive indices for neutrons. An ion beam sputtering instrument with an effective deposition area of 0.2 m has been installed at the Japan Atomic Energy Agency in order to produce neutron guides, benders, and other neutron optical devices, which are planned for application in the J-PARC project. We have succeeded in fabricating the supermirror with large critical angle of and that with high reflectivity () for .
Isono, Takaaki; Kawano, Katsumi; Ozeki, Hidemasa; Saito, Toru; Nabara, Yoshihiro; Suwa, Tomone; Shimono, Mitsugu; Ebisawa, Noboru; Sato, Minoru; Uno, Yasuhiro; et al.
no journal, ,
JAEA is procuring conductors for ITER Central Solenoid (CS) and has evaluated its superconducting performance using CS Model Coil Test facility. We measured Tcs values during cyclic charge of 16,000 cycles and warm-up and cool-down cycle of 3 times. And we measured effect of coil deformation by electro-magnetic force on Tcs values and performed quench test. In this presentation, test method will be reported.
Nabara, Yoshihiro; Suwa, Tomone; Ozeki, Hidemasa; Sakurai, Takeru; Kajitani, Hideki; Iguchi, Masahide; Hemmi, Tsutomu; Shimono, Mitsugu; Ebisawa, Noboru; Sato, Minoru; et al.
no journal, ,
no abstracts in English
Hamada, Kazuya; Nunoya, Yoshihiko; Takahashi, Yoshikazu; Isono, Takaaki; Nabara, Yoshihiro; Hemmi, Tsutomu; Matsui, Kunihiro; Kawano, Katsumi; Ebisawa, Noboru; Oshikiri, Masayuki; et al.
no journal, ,
The ITER Central Solenoid (CS) conductor is composed of 576 NbSn superconducting strands and 288 Cu strands assembled together into a multistage cable and protected by a circle-in-square jacket with the outer dimension of 49 mm 49 mm. In R&D to prepare for the ITER CS conductor manufacturing, full size conductor performance test and jacket welding test and mechanical tests have been performed. In the presentation, the R&D activities are presented, showing that as a result of this R&D, the CS conductor manufacturing technologies have been confirmed to start the procurement of the CS conductor.
Maruyama, Ryuji; Yamazaki, Dai; Ebisawa, Toru*; Soyama, Kazuhiko
no journal, ,
no abstracts in English