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JAEA Reports

Noise countermeasures for inverter-controlled multi-stage roots vacuum pumps in J-PARC LINAC L3BT

Takano, Kazuhiro; Kotoku, Hirofumi*; Kobayashi, Fuminori*; Miyao, Tomoaki*; Moriya, Katsuhiro; Kamiya, Junichiro

JAEA-Technology 2021-017, 35 Pages, 2021/11

JAEA-Technology-2021-017.pdf:5.32MB

In J-PARC LINAC, the vacuum system of L3BT, which is a beam transport line connecting LINAC and 3GeV synchrotron, uses a turbo molecular pump and roots pump for rough exhaust and an ion pump for main exhaust. In addition, beam dumps are connected to the end of the L3BT at 0 degree, 30 degree, 90 degree, and 100 degree positions via vacuum partition windows. The roots pumps are used as the exhaust system for each beam dump. The roots pump controllers have been installed away from the pump in the accelerator tunnel to avoid radiation damages. Besides, the special controllers, which have no inverter circuit inside, have been used to reduce the electrical noise on the beam loss monitors nearby. However, using the special controller without inverters, several problems have occurred such as the instability or wide variability of the pumping speed. To solve such problems, the roots pump controller with the inverter circuit must be used after reducing the electrical noise. In this report, some countermeasures to reduce the electrical noise from the inverters were investigated. The noise reduction circuit was successfully optimized to the level where the beam loss monitors works unaffected.

JAEA Reports

Carrying-out of whole nuclear fuel materials in Plutonium Research Building No.1

Inagawa, Jun; Kitatsuji, Yoshihiro; Otobe, Haruyoshi; Nakada, Masami; Takano, Masahide; Akie, Hiroshi; Shimizu, Osamu; Komuro, Michiyasu; Oura, Hirofumi*; Nagai, Isao*; et al.

JAEA-Technology 2021-001, 144 Pages, 2021/08

JAEA-Technology-2021-001.pdf:12.98MB

Plutonium Research Building No.1 (Pu1) was qualified as a facility to decommission, and preparatory operations for decommission were worked by the research groups users and the facility managers of Pu1. The operation of transportation of whole nuclear materials in Pu1 to Back-end Cycle Key Element Research Facility (BECKY) completed at Dec. 2020. In the operation included evaluation of criticality safety for changing permission of the license for use nuclear fuel materials in BECKY, cask of the transportation, the registration request of the cask at the institute, the test transportation, formulation of plan for whole nuclear materials transportation, and the main transportation. This report circumstantially shows all of those process to help prospective decommission.

Journal Articles

Improved vacuum system for high-power proton beam operation of the rapid cycling synchrotron

Kamiya, Junichiro; Kotoku, Hirofumi*; Kurosawa, Shunta*; Takano, Kazuhiro; Yanagibashi, Toru*; Yamamoto, Kazami; Wada, Kaoru

Physical Review Accelerators and Beams (Internet), 24(8), p.083201_1 - 083201_23, 2021/08

 Times Cited Count:0 Percentile:0.03(Physics, Nuclear)

Through the operation of the vacuum system in J-PARC, it becomes evident that the high-power beam has more powerful effects on the vacuum system than expected. Those effects are the malfunction of vacuum equipment and the large pressure rise. The former is the failure of the turbomolecular pump (TMP) controller. The TMP itself is also damaged by a bearing crush due to a touch-down. We have developed a TMP controller that can connect with long cables of more than 200 m lengths to install the controller in a control room where there is no radiation influence. The TMP with high-strength bearing has been also developed. The latter is an extreme pressure rise with increasing the beam power. It is indicated that the pressure rise mechanism is a result of ion-stimulated gas desorption. It is finally confirmed that the dynamic pressure during the high-power beam is effectually suppressed by additionally installing the NEG pumps.

Journal Articles

Some methods of making titanium vacuum chamber act as getter pump for UHV/XHV

Kamiya, Junichiro; Takano, Kazuhiro; Yuza, Hiromu*; Wada, Kaoru

Proceedings of 12th International Particle Accelerator Conference (IPAC 21) (Internet), p.3471 - 3474, 2021/08

The NEG coating, which has been developed in CERN, is a revolutionary technique that can make a beam pipe act as a vacuum pump by coating the getter materials with the ability to adsorb/absorb gas molecules on the beam pipe surface. The NEG materials are alloys of titanium, zirconium, and vanadium. Titanium is one of the getter materials. In high-power beam accelerators, titanium has been used as the beam pipe chamber material due to its low radioactivation characteristics. The ordinal titanium surface has no getter function because it is covered with titanium-oxide film. The new technique, which removes the titanium-oxide surface by the sputtering and makes the titanium vacuum chamber itself the vacuum pump like NEG coated chamber, has been developed. After sputtering the inner surface of the titanium chamber, we obtained clear evidence that shows the chamber acts as a vacuum pump. We have also tried to make a titanium chamber with a getter function only by baking. Dependence of the getter characteristics on the baking temperature will also be reported.

Journal Articles

Int. Conf. on Nuclear Data for Science and Technology

Shibata, Keiichi; Fukahori, Tokio; Takano, Hideki; *; Watanabe, Yukinobu*; Kobayashi, Katsuhei*; *; Oyamatsu, Kazuhiro*

Nihon Genshiryoku Gakkai-Shi, 39(10), p.863 - 865, 1997/00

no abstracts in English

Oral presentation

The Ibaraki prefecture materials design diffractometer for J-PARC

Ishigaki, Toru; Harjo, S.; Yonemura, Masao*; Kamiyama, Takashi*; Mori, Kazuhiro*; Mochiku, Takashi*; Aizawa, Kazuya; Arai, Masatoshi; Ebata, Kazuhiro*; Takano, Yoshiki*

no journal, , 

no abstracts in English

Oral presentation

Ibaraki biological crystal diffractometer in J-PARC (BIX-P1); Optimization of design parameters

Kusaka, Katsuhiro; Ohara, Takashi; Tanaka, Ichiro*; Niimura, Nobuo*; Ozeki, Tomoji*; Kurihara, Kazuo; Aizawa, Kazuya; Morii, Yukio; Arai, Masatoshi; Ebata, Kazuhiro*; et al.

no journal, , 

The TOF neutron biological diffractometer in J-PARC proposed by Ibaraki prefectural government is designed to cover the samples have their cell edges up to 135A, and to realize the efficiency is more than 50 times larger than the present high performance diffractometer, BIX-4. To achieve this performance, the diffractometer will be installed on a coupled moderator has more intense peak but wider pulse shape. The overlapping of Bragg spots along the time-axis expected should be considered for the determination of optic parameters and it is necessary to de-convolute the overlapped spots with higher accuracy. The original simulation programs of TOF diffraction data were developed to obtain information of spot-overlapping, completeness of Bragg spots and spot profiles along time-axis. In this paper, the consideration of important designed parameters focused on biological macromolecular and the strategy of de-convoluting overlapped spots will be reported based on the simulation results.

Oral presentation

Ibaraki materials design diffractometer for J-PARC

Ishigaki, Toru; Hoshikawa, Akinori; Yonemura, Masao*; Kamiyama, Takashi*; Harjo, S.; Aizawa, Kazuya; Sakuma, Takashi*; Tomota, Yo*; Morii, Yukio; Arai, Masatoshi; et al.

no journal, , 

Ibaraki prefecture, the local goverment of the area for J-PARC site, was decided to build a versatile neutron diffractometer (IBARAKI Materials Design Diffractometer) to promote a industrial application for neutron beam in J-PARC. This diffractometer is planned to be a high throughput diffractometer so that materials engineers and scientists can use it like the chemical analytical instruments in their materials development process. It covers in d range 0.18 $$<$$ d (${AA}$) $$<$$ 5 with $$Delta $$ $$d/d$$ = 0.16% at high resolution bank, and covers 5 $$<$$ d (${AA}$) $$<$$ 800 with gradually changing resolution at three detector bank (90 degree, low angle and small angle). Typical measuring time to obtain a "Rietveld-quality" data is several minutes with the sample size of laboratory X-ray diffractometer. To promote industrial application, a utilization system for this diffractometer is required. We will establish a support system for both academic and industrial users who are willing to use neutron but have not been familiar with neutron diffraction. The construction of this instrument was already begun and will be compleated in the beggining of 2008, as one of day-one instruments for J-PARC.

Oral presentation

Design of the neutron optics for Ibaraki biomolecular diffractometer

Ohara, Takashi; Kurihara, Kazuo; Kusaka, Katsuhiro; Hosoya, Takaaki; Tanaka, Ichiro*; Niimura, Nobuo*; Ozeki, Tomoji*; Aizawa, Kazuya; Morii, Yukio; Arai, Masatoshi; et al.

no journal, , 

no abstracts in English

Oral presentation

Present status for Ibaraki materials design diffractometer

Ishigaki, Toru; Hoshikawa, Akinori; Yonemura, Masao*; Kamiyama, Takashi*; Mori, Kazuhiro*; Mochiku, Takashi*; Aizawa, Kazuya; Arai, Masatoshi; Ebata, Kazuhiro*; Takano, Yoshiki*; et al.

no journal, , 

no abstracts in English

Oral presentation

Current status of IBARAKI biological diffractometer in J-PARC; Optimization of design parameters

Kusaka, Katsuhiro; Ohara, Takashi; Tanaka, Ichiro*; Niimura, Nobuo*; Kurihara, Kazuo; Hosoya, Takaaki; Ozeki, Tomoji*; Aizawa, Kazuya; Morii, Yukio; Arai, Masatoshi; et al.

no journal, , 

Ibaraki prefecture has started to construct IBARAKI biological crystal diffractometer for industrial use at MLF, J-PARC. It is designed to achieve the efficiency which is more than 50 times larger than the present high performance diffractometer BIX-4. To realize this performance, the diffractometer will be installed on a coupled moderator has more intense peak but wider pulse shape than a decoupled one. It is expected that some neighbor Bragg spots will overlap partially each other along the time axis. The overlapping of Bragg spots should be considered for optimization of design parameters and it is necessary to de-convolute the overlapped spots. The three original simulation programs of TOF diffraction data with designed parameters of the diffractometer were developed to obtain information of spot-overlapping, completeness of Bragg spots and spot profiles along the time axis. The consideration of important designed parameters will be reported based on the simulation results.

Oral presentation

Optimization of designparameters for Ibaraki Biological diffractometer in J-PARC by simulations of TOF diffraction data

Kusaka, Katsuhiro; Ohara, Takashi; Tanaka, Ichiro*; Niimura, Nobuo*; Kurihara, Kazuo; Hosoya, Takaaki; Ozeki, Tomoji*; Aizawa, Kazuya; Morii, Yukio; Arai, Masatoshi; et al.

no journal, , 

no abstracts in English

Oral presentation

IBARAKI materials design diffractometer; Versatile neutron diffractometer at J-PARC

Ishigaki, Toru; Hoshikawa, Akinori; Yonemura, Masao*; Kamiyama, Takashi*; Aizawa, Kazuya; Sakuma, Takashi*; Tomota, Yo*; Morii, Yukio; Arai, Masatoshi; Hayashi, Makoto*; et al.

no journal, , 

Ibaraki prefecture, the local government of the area for J-PARC site, was decided to build a versatile neutron diffractometer (IBARAKI Materials Design Diffractometer) to promote an industrial application for neutron beam in J-PARC. This diffractometer is planned to be a high throughput diffractometer so that materials engineers and scientists can use it like the chemical analytical instruments in their materials development process. It covers in d range 0.18 $$<$$ d (${AA}$) $$<$$ 5 with $$Delta$$ d/d = 0.16 % at high resolution bank, and covers $$<$$ d (${AA}$) $$<$$ 800 with gradually changing resolution at three detector bank (90 degree, low angle and small angle). Typical measuring time to obtain a "Rietveld-quality" data is several minutes with the sample size of laboratory X-ray diffractometer. To promote industrial application, a utilization system for this diffractometer is required. We will establish a support system for both academic and industrial users who are willing to use neutron but have not been familiar with neutron diffraction. The construction of this instrument was already beginning and will be completed in the beginning of 2008, as one of day-one instruments for J-PARC. The current status for this instrument also will be reported.

Oral presentation

Current status of IBARAKI biological diffractometer in J-PARC; Design of the neutron optics

Ohara, Takashi; Kurihara, Kazuo; Kusaka, Katsuhiro; Hosoya, Takaaki; Tanaka, Ichiro*; Niimura, Nobuo*; Ozeki, Tomoji*; Aizawa, Kazuya; Morii, Yukio; Arai, Masatoshi; et al.

no journal, , 

Ibaraki Prefectural Government in Japan has started to construct a TOF single crystal neutron diffractometer for biological macromolecules for industrial use at J-PARC. For this diffractometer, design of an efficient neutron transportation system is important because this diffractometer has 40m source-sample distance. Recently, we designed a supermirror neutron guide which can transport 0.7-3.8 Angstrom neutron efficiently. The total length of the mirror section is 25m. At the first 17m, the mirror has curvature (R=4300m) for horizontal direction in order to remove high-energy neutron and $$gamma$$ ray. Simultaneously, all of the mirror section has tapered angle for vertical direction in order to reduce the frequency of neutron reflection at the surface of the supermirror. The neutron flux and profile at the sample position was calculated by Monte Carlo simulation softwares, McStas and IDEAS and compared with a curved, non-tapered guide we had designed previously. In result, the new supermirror system has 2 times gain for 0.7 Angstrom neutron and 1.5 times for 1.5 Angstrom neutron, and the beam profile at the sample position has a rectangular shape.

Oral presentation

Current status of IBARAKI biological diffractometer in J-PARC; Detector configuration and data reduction

Kusaka, Katsuhiro; Ohara, Takashi; Tanaka, Ichiro*; Niimura, Nobuo*; Kurihara, Kazuo; Hosoya, Takaaki; Ozeki, Tomoji*; Aizawa, Kazuya; Morii, Yukio; Arai, Masatoshi; et al.

no journal, , 

Ibaraki prefecture has started to construct IBARAKI biological crystal diffractometer for industrial use at MLF, J-PARC. It is designed to achieve the efficiency which is more than 50 times larger than the present high performance diffractometer BIX-4. To realize this performance, the diffractometer will be installed on a coupled moderator has more intense peak but wider pulse shape than a decoupled one. It is expected that some neighbor Bragg spots will overlap partially each other along the time axis. We should develop the data reduction software system for the diffractometer including the program of peak de-convolution with fast algorism. The detector configuration should be also important to realize high performance for measurement speed and data accuracy. The strategy of data collection, the strategy of de-convoluting overlapped Bragg spots and its validity will be reported based on the results of the simulations with the original programs.

Oral presentation

Current status of IBARAKI biological crystal diffractometer in J-PARC

Tanaka, Ichiro*; Ohara, Takashi; Kurihara, Kazuo; Kusaka, Katsuhiro*; Hosoya, Takaaki; Tomoyori, Katsuaki*; Niimura, Nobuo*; Ozeki, Tomoji*; Aizawa, Kazuya; Arai, Masatoshi; et al.

no journal, , 

IBARAKI Biological Crystal Diffractometer is a new single-crystal neutron diffractometer for biological and chemical crystallography, and is now being constructed at J-PARC by Ibaraki Prefectural Government in Japan. This diffractometer is designed for the protein crystals with the cell dimension up to 135 ${AA}$. The measurement efficiency is more than 50 times larger than the present neutron diffractometer, BIX-3/BIX-4 in JRR-3 reactor at JAEA. To achieve this performance, we have selected a coupled moderator, and worked out the optimisation of the neutron guide tube. For the detector, a new wavelength-shifting-fiber type scintillation area detector system with high spatial (0.5-1.0 mm) and time (1ms-) resolution are in development.

Oral presentation

Development of fabrication technique of optical devices using ion beam

Miura, Kenta*; Umenyi, A. V.*; Hanaizumi, Osamu*; Sato, Takahiro; Ishii, Yasuyuki; Okubo, Takeru; Yamazaki, Akiyoshi; Koka, Masashi; Yokoyama, Akihito; Kada, Wataru; et al.

no journal, , 

no abstracts in English

Oral presentation

Characterization of the ion-beam induced UVB-sensitive rice mutant ${it usr1}$

Chiba, Kazuhiro*; Takano, Nao*; Yamamoto, Mitsuru*; Teranishi, Mika*; Hase, Yoshihiro; Sakamoto, Ayako; Tanaka, Atsushi; Hidema, Jun*

no journal, , 

no abstracts in English

Oral presentation

Fabrication of optical functional elements by ion beam

Miura, Kenta*; Kikuchi, Shusuke*; Kiryu, Hiromu*; Inada, Kazuki*; Ozawa, Yusuke*; Hanaizumi, Osamu*; Yamamoto, Shunya; Sugimoto, Masaki; Yoshikawa, Masahito; Kawaguchi, Kazuhiro; et al.

no journal, , 

no abstracts in English

Oral presentation

Dynamic pressure in the high-power beam operation at J-PARC RCS

Kamiya, Junichiro; Yamamoto, Kazami; Takano, Kazuhiro; Kotoku, Hirofumi; Wada, Kaoru*; Yanagibashi, Toru*; Kurosawa, Shunta*

no journal, , 

The vacuum system in the rapid cycling synchrotron of Japan Proton Accelerator Research Complex was constructed based on the design concept considering the effect of a dynamic pressure caused by a high-power proton beam operation. However, the high-power beam operation clearly has more effects than expected at the time of the design. The dynamic pressure with the beamline pressure runaway characterized by an extreme pressure rise of more than orders of magnitude occurred during beam operation. A systematic data observation showed that the pressure rise mechanism is a result of the gas desorption from the wall triggered by the hitting of the residual gas molecules ionized by the proton beam. The numerical calculation based on that model well reproduced the measured dynamic pressure behaviors in the beam operation. The calculation also showed that a large pumping speed and a small surface density of the adsorbed molecules are required to suppress the pressure runaway.

22 (Records 1-20 displayed on this page)