SENJU; A New time-of-flight single-crystal neutron diffractometer at J-PARC

Ohara, Takashi; Kiyanagi, Ryoji; Oikawa, Kenichi; Kaneko, Koji; Kawasaki, Takuro; Tamura, Itaru; Nakao, Akiko*; Hanashima, Takayasu*; Munakata, Koji*; Moyoshi, Taketo*; et al.

Journal of Applied Crystallography, 49(1), p.120 - 127, 2016/02

https://doi.org/10.1107/S1600576715022943

Instrument design and performance evaluation of a new single crystal neutron diffractometer SENJU at J-PARC

Oikawa, Kenichi; Kawasaki, Takuro; Ohara, Takashi; Kiyanagi, Ryoji; Kaneko, Koji; Tamura, Itaru; Nakamura, Tatsuya; Harada, Masahide; Nakao, Akiko*; Hanashima, Takayasu*; et al.

JPS Conference Proceedings (Internet), 1, p.014013_1 - 014013_5, 2014/03

https://doi.org/10.7566/JPSCP.1.014013

A new single crystal time-of-flight neutron diffractometer has been installed at BL18 of the Materials and Life Science Experimental Facility of J-PARC. The diffractometer "SENJU" was designed for precise crystal and magnetic structure analyses using a small crystal less than 1.0 mm under multiple extreme environments such as low-temperature and high-magnetic field. The first neutron beam was delivered to the sample position on March 5, 2012. Subsequently, the hardware and software of SENJU have been checked and confirmed that they worked fine. At the same time, diffraction experiments of several organic and inorganic crystals have been done using NaCl, C12A7, and so on. In these measurements, Bragg reflections in the high-Q region (d-spacing 0.5 ) were clearly observed and analyzed successfully. In this presentation, we will show the instrument design and performance evaluation of SENJU in detail.

Current status of a time-of-flight single crystal neutron diffractometer SENJU at J-PARC

Tamura, Itaru; Oikawa, Kenichi; Kawasaki, Takuro; Ohara, Takashi; Kaneko, Koji; Kiyanagi, Ryoji; Kimura, Hiroyuki*; Takahashi, Miwako; Kiyotani, Tamiko*; Arai, Masatoshi; et al.

Journal of Physics; Conference Series, 340, p.012040_1 - 012040_4, 2012/02

https://doi.org/10.1088/1742-6596/340/1/012040

X-ray reciprocal space mapping of dislocation-mediated strain relaxation during InGaAs/GaAs(001) epitaxial growth

Sasaki, Takuo*; Suzuki, Hidetoshi*; Takahashi, Masamitsu; Oshita, Yoshio*; Kamiya, Itaru*; Yamaguchi, Masafumi*

Journal of Applied Physics, 110(11), p.113502_1 - 113502_7, 2011/12

https://doi.org/10.1063/1.3664832

Growth temperature dependence of strain relaxation during InGaAs/GaAs(0 0 1) heteroepitaxy

Sasaki, Takuo*; Suzuki, Hidetoshi*; Sai, Akihisa*; Takahashi, Masamitsu; Fujikawa, Seiji; Kamiya, Itaru*; Oshita, Yoshio*; Yamaguchi, Masafumi*

Journal of Crystal Growth, 323(1), p.13 - 16, 2011/05

https://doi.org/10.1016/j.jcrysgro.2010.10.005

Growth temperature dependence of strain relaxation during InGaAs/GaAs(001) molecular beam epitaxy was studied by in situ X-ray reciprocal space mapping. Evolution of the residual strain and crystal quality for the InGaAs film was obtained as a function of film thickness at growth temperatures of 420, 445 and 477 C. In the early stages of strain relaxation, it was found that evolution of the residual strain and crystal quality was dependent on the growth temperature. In order to discuss this observation quantitatively, the strain relaxation model was proposed based on the Dodson-Tsao kinetic model, and its validity was demonstrated by good agreement with the experimental residual strain. Additionally, rate coefficients reflecting dislocation motions during strain relaxation were obtained as a function of growth temperature and strain relaxation was discussed in terms of the thermally active dislocation motion.

real-time X-Ray reciprocal space mapping during InGaAs/GaAs growth for understanding strain relaxation mechanisms

Sasaki, Takuo*; Suzuki, Hidetoshi*; Sai, Akihisa*; Lee, J.-H.*; Takahashi, Masamitsu; Fujikawa, Seiji; Arafune, Koji*; Kamiya, Itaru*; Oshita, Yoshio*; Yamaguchi, Masafumi*

Applied Physics Express, 2, p.085501_1 - 085501_3, 2009/07

https://doi.org/10.1143/APEX.2.085501

Instrumental design of indirect geometry crystal analyzer spectrometer; DNA at J-PARC

Shibata, Kaoru; Takahashi, Nobuaki; Nakagawa, Hiroshi; Fujiwara, Satoru; Kataoka, Mikio; Sato, Taku*; Kawakita, Yukinobu*; Tsukushi, Itaru*

Nihon Kessho Gakkai-Shi, 50(1), p.46 - 50, 2008/02

https://doi.org/10.5940/jcrsj.50.46

The instrumental design of an indirect geometry crystal analyzer spectrometer: DNA which is scheduled to be constructed in the Material and Life Science experimental Facility (MLF) at J-PARC, is reported in this article. This spectrometer is mainly aimed at searching for the high quality inelastic scattering spectra with only several mg order biomolecular sample in the plenty of wide range of energy and momentum transfers.

Study of the instrumental detailed design on near-backscattering spectrometers DNA

Shibata, Kaoru; Takahashi, Nobuaki; Sato, Taku*; Kawakita, Yukinobu*; Tsukushi, Itaru*; Nakagawa, Hiroshi; Fujiwara, Satoru; Nakajima, Kenji; Arai, Masatoshi

no journal, , 

no abstracts in English

Potential of 1 micro-eV energy resolution of the Si-analyzer backscattering spectrometer DNA at the spallation neutron source J-PARC

Takahashi, Nobuaki; Shibata, Kaoru; Sato, Taku*; Kawakita, Yukinobu*; Tsukushi, Itaru*; Nakajima, Kenji; Arai, Masatoshi

no journal, , 

A time-of-flight Si-analyzer backscattering spectrometer (BSS) DNA is proposed for construction in the Materials and Life Science Facility (MLF) of Japan Proton Accelerator Research Complex (J-PARC) located in Tokai, Ibaraki, Japan. Four crystal analyzer sets, namely Si(111), Si(311), PG(002) and Ge(311) had been planned to be mounted on it in near-backscattering configurations in two evacuated tanks in order to cover wide energy and momentum transfer ranges that suit research on the dynamics of bio-molecules and proteins. After extensive discussion with instrument scientists of BSSs as well as biophysicists in the committee the highest energy resolution option provided by the Si analyzer came to the highest priority. Therefore the design of the DNA has been rather simplified. Si(111) and Si(311) analyzers will be mounted in a vacuum vessel putting at 43 m away from a coupled moderator to enjoy the highest peak intensity around several meV, which is the elastic energies of the Si analyzers, among three moderators of JSNS, namely the coupled, a decoupled and a decoupled-poison. Because the pulse time-width of the coupled moderator is the widest of the three, it is designed to utilize a pulse-shaping device, which is high speed counter rotating disc choppers, on the beamline staying as far away from the sample position as possible to narrow the time-width. In this paper we will present the conceptual design and the expected performance of the pulse-shape short-flight-length BSS DNA. The obtainable performance will be compared with BSSs at reactor sources as well as a decoupled-poisoned-moderator-source long-flight-length BSS at a spallation neutron source.

Study of thermal diffuse scattering from single crystal in near-backscattering TOF neutron diffraction

Shibata, Kaoru; Takahashi, Nobuaki; Tsukushi, Itaru*; Kawakita, Yukinobu*; Sato, Taku*; Nakajima, Kenji; Arai, Masatoshi

no journal, , 

We will report the experimental results of thermal diffuse scattering (TDS) which occurs close to the Bragg reflections in time-of-flight neutron diffraction. We measured the thermal diffuse scatterings around some analyzer crystals Bragg peaks; pyrolitic graphite PG(002), perfect silicon Si(111) and natural green mica: Mica(006).