A Terrestrial SER Estimation Methodology Based on Simulation Coupled With One-Time Neutron Irradiation Testing

Abe, Shinichiro; Hashimoto, Masanori*; Liao, W.*; Kato, Takashi*; Asai, Hiroaki*; Shimbo, Kenichi*; Matsuyama, Hideya*; Sato, Tatsuhiko; Kobayashi, Kazutoshi*; Watanabe, Yukinobu*

IEEE Transactions on Nuclear Science, 70(8, Part 1), p.1652 - 1657, 2023/08

https://doi.org/10.1109/TNS.2023.3280190

Single event upsets (SEUs) caused by neutrons is a reliability problem for microelectronic devices in the terrestrial environment. Acceleration tests using white neutron beam provide realistic soft error rates (SERs), but only a few facilities can provide white neutron beam in the world. If single-source irradiation applicable to diverse neutron source can be utilized for the evaluation of the SER in the terrestrial environment, it contributes to solve the shortage of beam time. In this study, we investigated the feasibility of the SER estimation in the terrestrial environment by any one of these measured data with the SEU cross sections obtained by PHITS simulation. It was found that the SERs estimated by our proposed method are within a factor of 2.7 of that estimated by the Weibull function. We also investigated the effect of simplification which reduce the computational cost in simulation to the SER estimation.

Dimensional reduction by geometrical frustration in a cubic antiferromagnet composed of tetrahedral clusters

Okuma, Ryutaro*; Kofu, Maiko; Asai, Shinichiro*; Avdeev, M.*; Koda, Akihiro*; Okabe, Hirotaka*; Hiraishi, Masatoshi*; Takeshita, Soshi*; Kojima, Kenji*; Kadono, Ryosuke*; et al.

Nature Communications (Internet), 12, p.4382_1 - 4382_7, 2021/07

https://doi.org/10.1038/s41467-021-24636-1

Spin state of Co in LaCo RhO investigated by structural phenomena

Asai, Shinichiro*; Okazaki, Ryuji*; Terasaki, Ichiro*; Yasui, Yukio*; Kobayashi, Wataru*; Nakao, Akiko*; Kobayashi, Kensuke*; Kumai, Reiji*; Nakao, Hironori*; Murakami, Yoichi*; et al.

Journal of the Physical Society of Japan, 82(11), p.114606_1 - 114606_6, 2013/11

https://doi.org/10.7566/JPSJ.82.114606

Neutron and synchrotron X-ray diffraction for LaCo RhO have been carried out in order to investigate the structural properties related with the spin state of Co ions. We have found that the values of the Co(Rh)-O bond lengths in the Co(Rh)O octahedron of LaCoRhO are nearly identical at 10 K. The lattice volume for the Rh substituted samples decreases with the thermal expansion coefficient similar to that of LaCoO from room temperature, and ceases to decrease around 70 K. These experimental results favor a mixed state consisting of the high-spin state and low-spin state Co ions, and suggest that the high-spin state Co ions are thermally excited in addition to those pinned by the substituted Rh ions.

Countermeasures planned for reducing water inflow into deep shafts at the Mizunami Underground Research Laboratory (Research for post-excavation grouting)

Kuji, Masayoshi*; Matsui, Hiroya; Hara, Masato; Minamide, Masashi*; Mikake, Shinichiro; Takeuchi, Shinji; Sato, Toshinori*; Asai, Hideaki

JAEA-Research 2008-095, 54 Pages, 2009/01

JAEA-Research-2008-095.pdf:13.14MB

A large amount of water inflow is frequently generated during the excavation of an underground cavern, such as road and railway tunnels, underground electric facilities etc. The reduction of water inflow is sometimes quite important for the reduction of cost for the water treatment and pumping during the construction of an underground cavern. The Mizunami Underground Research Laboratory (MIU) is currently being constructed by Japan Atomic Energy Agency. During its excavation, a large amount of water inflow into the shafts has been increasing and affecting the project progress. Therefore, a field experiment of post-excavation grouting around the Ventilation Shaft in a sedimentary formation carried out to confirm the effect of existing grouting technology for sedimentary formations in MIU project. The result shows that the applied methods in this field experiment are effective to prevent water inflow. This report describes the summary of the field experiment and the knowledge obtained through the experiment.

Studies on engineering technologies in the Mizunami Underground Research Laboratory

Matsui, Hiroya; Mikake, Shinichiro; Asai, Hideaki; Sugihara, Kozo

no journal, , 

In the construction phase of the MIU project, engineering studies have focused on research into design and construction technologies for deep underground. The main subjects consist of the following: "Demonstration of the design methodology", "Demonstration of existing and supplementary excavation methods", "Demonstration of countermeasures during excavation" and "Demonstration of safe construction". In the FY 2007, identification and evaluation of the subjects for this study were carried out to optimize future research work. Specific studies have been performed as well. Based on these studies, future research focused on the four subject areas has been identified. The design methodology in the surface-based investigation phase was verified to 200 m depth. Evaluation of countermeasures and studies of concepts for the estimation of the influence of high differential water pressures, long-term maintenance and risk management have been proposed with respect to the geological disposal project.

Mizunami Underground Research Laboratory Project, 2; Current status of development of engineering technology for deep underground

Asai, Hideaki; Matsui, Hiroya; Mikake, Shinichiro; Ito, Hiroaki; Horiuchi, Yasuharu; Ishii, Yoji

no journal, , 

The Mizunami Underground Research Laboratory (MIU) is currently being constructed by Japan Atomic Energy Agency. As part of MIU Project, development of engineering technology for deep underground intended for the crystalline rock is executed. The research to confirm the effectiveness of engineering technology is being executed during its excavation now. It reports on study results up to 300m in depth of engineering technology research and the schedule for the future.

Nuclear structure studies of Es region by Coulomb excitation -ray spectroscopy

Yanagihara, Rikuto; Ideguchi, Eiji*; Nishio, Katsuhisa; Orlandi, R.; Makii, Hiroyuki; Asai, Masato; Hirose, Kentaro; Tsukada, Kazuaki; Toyoshima, Atsushi; Sato, Tetsuya; et al.

no journal, ,