Study on engineering technologies in the Mizunami Underground Research Laboratory (FY 2012) (Contract research)

Fukaya, Masaaki*; Noda, Masaru*; Hata, Koji*; Takeda, Nobufumi*; Akiyoshi, Kenji*; Ishizeki, Yoshikazu*; Kaneda, Tsutomu*; Sato, Shin*; Shibata, Chihoko*; Ueda, Tadashi*; et al.

JAEA-Technology 2014-019, 495 Pages, 2014/08

JAEA-Technology-2014-019.pdf:82.23MB

The researches on engineering technology in the Mizunami Underground Research Laboratory (MIU) plan consists of (1) research on engineering technology deep underground, and (2) research on engineering technology as a basis of geological disposal. The former research is mainly aimed in this study, which is categorized in (a) development of design and construction planning technologies, (b) development of construction technologies, (c) development of countermeasure technologies, and (d) development of technologies for security. In this study, the researches on engineering technology are being conducted in these four categories by using data measured during construction as a part of the second phase of the MIU plan.

Small-angle polarized neutron scattering study of spherical FeN nano-particles for magnetic recording tape

Oku, Takayuki; Kikuchi, Takayuki*; Shinohara, Takenao; Suzuki, Junichi; Ishii, Yuya*; Takeda, Masayasu; Kakurai, Kazuhisa; Sasaki, Yuji*; Kishimoto, Mikio*; Yokoyama, Makoto*; et al.

Physica B; Condensed Matter, 404(17), p.2575 - 2577, 2009/09

https://doi.org/10.1016/j.physb.2009.06.027

The microscopic determination of the magnetic moment in the FeN nano-particles by means of polarized neutron diffraction experiment is reported. These particles had been developed by industrial researchers for use in high-density magnetic tape, and the particles were coated with proprietary nonmagnetic material. Polarized neutrons were used to measure the magnetic-nuclear interference contributions and, given the known crystal structure, the detailed analysis allowed to determine the magnetic moments on the different Fe-sites. The future perspectives of this technique using the high-intensity powder instrument in combination with pulsed magnetic high-field at J-PARC including the possible industrial application is discussed.

JAEA photocathode DC-gun for an ERL injector

Nishitani, Tomohiro; Hajima, Ryoichi; Iijima, Hokuto; Nagai, Ryoji; Sawamura, Masaru; Kikuzawa, Nobuhiro; Nishimori, Nobuyuki; Minehara, Eisuke; Tabuchi, Masao*; Noritake, Yosuke*; et al.

Proceedings of 28th International Free Electron Laser Conference (FEL 2006) (CD-ROM), p.319 - 322, 2006/08

ERL light source and FEL require an electron beam of large current and small emittance. In order to realize an electron gun satisfying such requirements,we started developments of a photocathode DC-gun and a new-type NEA-photocathode. The DC-gun consists of a chamber to activate NEA-surface, a 250 keV acceleration chamber, and a mode-locked Ti:Sapphire laser. Since extreme high vacuum is essential to obtain a long-life photocathode, we adopt a load-lock system for transporting a photocathode between the chambers, each of which is equipped with an NEG pump. Up to now, we fabricated an electrodes chamber and a high voltage terminal of 250 kV and we succeeded in a 250kV high voltage test. We also have suggested a superlattice photocathode as a new-type photocathode with higher performance than an existing technology. Up to now, we fabricated photocathode samples by molecular beam epitaxy and measured a quantum efficiency after NEA-surface activation.

Highly polarized electrons from GaAs-GaAsP and InGaAs-AlGaAs strained-layer superlattice photocathodes

Nishitani, Tomohiro; Nakanishi, Tsutomu*; Yamamoto, Masahiro*; Okumi, Shoji*; Furuta, Fumio*; Miyamoto, Masaharu*; Kuwahara, Makoto*; Yamamoto, Naoto*; Naniwa, Kenichi*; Watanabe, Osamu*; et al.

Journal of Applied Physics, 97(9), p.094907_1 - 094907_6, 2005/05

https://doi.org/10.1063/1.1886888

no abstracts in English

A Polarized SANS study of spherical Fe-N nanoparticles for magnetic recording tape, 2

Kikuchi, Takayuki; Oku, Takayuki; Shinohara, Takenao; Suzuki, Junichi; Ishii, Yuya; Takeda, Masayasu; Kakurai, Kazuhisa; Sasaki, Yuji*; Kishimoto, Mikio*; Yokoyama, Makoto*; et al.

no journal, , 

no abstracts in English

A Small-angle polarized neutron scattering study of spherical Fe-N particles for magnetic recording tape

Oku, Takayuki; Kikuchi, Takayuki; Shinohara, Takenao; Suzuki, Junichi; Ishii, Yuya; Takeda, Masayasu; Kakurai, Kazuhisa; Sasaki, Yuji*; Kishimoto, Mikio*; Yokoyama, Makoto*; et al.

no journal, , 

no abstracts in English

Evaluation of magnetic moments on particulate FeN by polarized neutrons

Ishii, Yuya; Takeda, Masayasu; Kakurai, Kazuhisa; Kikuchi, Takayuki; Shinohara, Takenao; Oku, Takayuki; Suzuki, Junichi; Sasaki, Yuji*; Kishimoto, Mikio*; Yokoyama, Makoto*; et al.

no journal, , 

no abstracts in English

Measurement of the magnetic form factor of -Fe and CoFe powder by polarized neutron diffraction

Oitani, Seiki; Ishii, Yuya; Takeda, Masayasu; Kakurai, Kazuhisa; Kikuchi, Takayuki; Oku, Takayuki; Shinohara, Takenao; Suzuki, Junichi; Yokoyama, Makoto*; Nishihara, Yoshikazu*; et al.

no journal, , 

no abstracts in English

NEA-AlGaAs photocathode high brightness electron source

Nishitani, Tomohiro; Hajima, Ryoichi; Takeda, Yoshikazu*; Tabuchi, Masao*; Noritake, Yosuke*; Hayashitani, Haruhiko*

no journal, , 

no abstracts in English

Polarized neutron diffractometry of FeN nanoparticles

Tamai, Yuta; Ishii, Yuya*; Hagiya, Hiroyuki; Kikuchi, Takayuki*; Yokoyama, Makoto*; Nishihara, Yoshikazu*; Takeda, Masayasu; Kakurai, Kazuhisa; Oku, Takayuki; Shinohara, Takenao; et al.

no journal, , 

Magnetic recording tape is widely used for a massive data storage with high reliability, and further increase of capacity, the recording density, is requested by IT organizations. The needle-shaped ferromagnetic metals has been used for the recording media. However, it is necessary to make the media a small and spherical shape to increase the recording density. We have performed the polarized neutron diffraction measurements of FeN round-shape nanoparticles, and determined the saturation magnetic moments and averaged core size of FeN nanoparticles covered by a laminate layer.