Development of spin-contrast-variation neutron powder diffractometry for extracting the structure factor of hydrogen atoms

Miura, Daisuke*; Kumada, Takayuki; Sekine, Yurina; Motokawa, Ryuhei; Nakagawa, Hiroshi; Oba, Yojiro; Ohara, Takashi; Takata, Shinichi; Hiroi, Kosuke; Morikawa, Toshiaki*; et al.

Journal of Applied Crystallography, 54(2), p.454 - 460, 2021/04

AA2020-0724.pdf:2.05MB

https://doi.org/10.1107/S1600576721000303

We developed a spin-contrast-variation neutron powder diffractometry technique that extracts the structure factor of hydrogen atoms, namely, the contribution of hydrogen atoms to a crystal structure factor. Crystals of L-glutamic acid were dispersed in a dpolystyrene matrix containing 4-methacryloyloxy-2,2,6,6,-tetramethyl-1-piperidinyloxy (TEMPO methacrylate) to polarize their proton spins dynamically. The intensities of the diffraction peaks of the sample changed according to the proton polarization, and the structure factor of the hydrogen atoms was extracted from the proton-polarization dependent intensities. This technique is expected to enable analyses of the structures of hydrogen-containing materials that are difficult to determine with conventional powder diffractometry.

Present status of J-PARC linac

Oguri, Hidetomo; Hasegawa, Kazuo; Ito, Takashi; Chishiro, Etsuji; Hirano, Koichiro; Morishita, Takatoshi; Shinozaki, Shinichi; Ao, Hiroyuki; Okoshi, Kiyonori; Kondo, Yasuhiro; et al.

Proceedings of 11th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.389 - 393, 2014/10

http://www.pasj.jp/web_publish/pasj2014/proceedings/PDF/FSP0/FSP021.pdf

no abstracts in English

Developments of high power gyrotron and power modulation technique using the JT-60U ECRF system

Kobayashi, Takayuki; Terakado, Masayuki; Sato, Fumiaki; Yokokura, Kenji; Shimono, Mitsugu; Hasegawa, Koichi; Sawahata, Masayuki; Suzuki, Sadaaki; Hiranai, Shinichi; Igarashi, Koichi; et al.

Plasma and Fusion Research (Internet), 4, p.037_1 - 037_10, 2009/08

https://doi.org/10.1585/pfr.4.037

Electron cyclotron (EC) heating and current drive (CD) are key tools to control fusion plasma especially for effective electron heating and for suppression of neoclassical tearing mode (NTM). Recently, developments of a high power gyrotron and a power modulation technique have been successfully achieved on JT-60U ECRF system in order to enhance the system performance. Stable gyrotron oscillation with oscillation power of 1.5 MW for 1 s was demonstrated in 2007, for the first time. Then temperature rise of cavity and collector has been investigated. It has been shown that the longer pulse operation with 1.5 MW by an improved 110 GHz gyrotron is possible. In addition, modulated ECCD in synchronized with NTM rotation has been performed with the oscillation power of 0.8 MW and the frequency around 5 kHz. The synchronizing system has worked very well and it has played an essential role in NTM suppression experiments on JT-60U.

Study on disassembly work of the radio frequency heating system in the amplifier rooms and heating power supply building

Yokokura, Kenji; Shimono, Mitsugu; Hasegawa, Koichi; Sawahata, Masayuki; Suzuki, Sadaaki; Terakado, Masayuki; Hiranai, Shinichi; Igarashi, Koichi; Sato, Fumiaki; Wada, Kenji; et al.

JAEA-Technology 2008-065, 98 Pages, 2008/10

JAEA-Technology-2008-065.pdf:38.83MB

Construction of the JT-60SA (super advanced) is planned as an upgrade of JT-60U as the satellite tokamak in ITER broader approach and as the national centralized tokamak facility program in Japan. The present JT-60U will be disassembled and the JT-60SA will be constructed at the same location in the JT-60 tours hall. The disassembly work will be planned in the period from 2009 to 2011. In this report, disassembly of the radio frequency heating system of JT-60U in the amplifier rooms and heating power supply building is studied on (1) object for disassembly, (2) work plan, (3) estimation of materials amount, (4) procedure.

Report on the expert committee on development and utilization of phantoms, 2

Saito, Kimiaki; Kinase, Sakae; Suzuki, Toshikazu*; Nakano, Takashi*; Sato, Yuichi*; Ishigure, Nobuhito*; Iwai, Satoshi*

Hoken Butsuri, 42(1), p.38 - 52, 2007/03

https://doi.org/10.5453/jhps.42.38

The expert committee on development and utilization of phantoms had activities from April, 2004 to March, 2006 sponsored by the Japan Health Physics Society. The purpose of the committee was to accumulate and share the latest information concerning phantoms and related technical issues, and to discuss how and for what phantoms should be utilized in future. The committee had twelve meetings and one symposium. Many people took part in the activity including the committee members, observers and other participants; we had a certain number of lectures covering versatile topics and chances to discuss essential problems including sophistication and standardization of phantoms. Some parts of the information we obtained in this activity have been presented in the articles in series.

Relaxation test data collection of the FBR structural material

Onizawa, Takashi; ; ; ;

JNC TN9450 2001-005, 245 Pages, 2001/08

JNC-TN9450-2001-005.pdf:5.11MB

FBR structural materials tests have been preformed in New Technology Development Group. Many valuable relaxation data in this report will be used for material examination of FBR in the future. Contents of the data sheet are as follows; (1)Material: SUS304, SUS316, SUS321, 316FR, 2.25Cr-1Mo Steel, Mod.9Cr-1Mo Steel, 9Cr-2Mo Steel, INCONEL718 (2)Test environment: In air (3)Test temperature: 400C to 650C (4)Test method: According to JIS and FBR Metallic Materials Test Method (5)Number of data: Total 343. These data are the printouts of "the structural material data processing system, SMAT".

Developments of antennas and transmission lines for ECH on JT-60U

Kobayashi, Takayuki; Moriyama, Shinichi; Yokokura, Kenji; Hasegawa, Koichi; Suzuki, Sadaaki; Hiranai, Shinichi; Sato, Fumiaki; Suzuki, Takashi; Wada, Kenji; Fujii, Tsuneyuki

no journal, , 

Developments of reliable transmission lines and antennas are important to high power and long pulse operations of electron cyclotron resonance heating (ECH) systems. Design study of an antenna concept, which has a reliable cooling and driving structure to alter wave injection angle in poloidal direction only by a linear motion of a mirror, is under way. For an effective current drive and an electron heating by ECH, a toroidal injection angle () should be optimized for each objective of the experiment. In this study, an available range of was evaluated. Due to a difference of the reflecting position on the movable mirror toward depth of a port for each , the available is limited for small . By a numerical calculation, it was found that 0 20 was available for = 0 by this antenna assuming the JT-60U ECH port. Therefore toroidal injection angle can be optimized for each experiment.

Software development for neutron experimental instruments at MLF, J-PARC

Nakatani, Takeshi; Inamura, Yasuhiro; Ito, Takayoshi; Kajimoto, Ryoichi; Aoyagi, Tetsuo; Ohara, Takashi; Otomo, Toshiya*; Yasu, Yoshiji*; Suzuki, Jiro*; Morishima, Takahiro*; et al.

no journal, , 

We have started the commissioning of the neutron scattering experiment instruments since May 2008 in MLF, J-PARC. Simultaneously, we have started the commissioning of the data acquisition and analysis software. Experimental users operate this software through the software framework which we have developed. The software framework was developed based on Python which is an object oriented script language. The system implemented with the software framework can seamlessly measure, analyze and visualize with some modules which are experimental control and data analysis. In this presentation, we report the process of the construction and the current status of the software.

Current status and future plan of the software framework in MLF computing environment

Nakatani, Takeshi; Inamura, Yasuhiro; Ito, Takayoshi; Kajimoto, Ryoichi; Harjo, S.; Arai, Masatoshi; Ohara, Takashi; Nakagawa, Hiroshi; Aoyagi, Tetsuo; Otomo, Toshiya*; et al.

no journal, , 

We have developed the software framework in MLF computing environment from 2006 to 2008. The software framework is the fundamental software for neutron and muon experimental instruments in J-PARC/MLF. Currently, the software framework is installed at 4D Space Access Neutron Spectrometer (BL01), IBARAKI Biological Crystal Diffractometer (BL03), Cold-Neutron Disk-Chopper Spectrometer (BL14), Engineering Materials Diffractometer (BL19) and High Intensity Total Diffractometer (BL21). The features of experimental control, analysis, visualization and authorization are already implemented in the software framework. In this year, we will start the development to introduce the feature of database. We will present the current status and future plan of the software framework.

Data processing software for a new TOF single crystal neutron diffractometer iBIX at J-PARC

Ohara, Takashi; Kusaka, Katsuhiro*; Hosoya, Takaaki*; Kurihara, Kazuo; Yamada, Taro*; Tomoyori, Katsuaki*; Yokoyama, Takeshi*; Onishi, Yuki*; Tanaka, Ichiro*; Niimura, Nobuo*; et al.

no journal, , 

For a single crystal diffractometer, a data processing software which extracts a HKLF list from raw data is one of the most important components. We have developed a new data processing software, named STARGazer, for a new TOF single crystal neutron diffractometer, IBARAKI Biological Crystal Diffractometer (iBIX), which is constructed at Materials and Life-science Facility (MLF) of J-PARC. We have already collected and processed neutron diffraction dataset of ammonium bitartrate, glutamic acid and some crystals of organic molecules. The obtained cell parameters agreed with the known values and positions of hydrogen atoms are reasonable. In this presentation, we will show the feature of STARGazer and also show the results of neutron structure analyses of the organic molecules by iBIX.