scattering length from photoproduction on the proton near the reaction threshold

Ishikawa, Takatsugu*; Fujimura, Hisako*; Fukasawa, Hiroshi*; Hashimoto, Ryo*; He, Q.*; Honda, Yuki*; Hosaka, Atsushi; Iwata, Takahiro*; Kaida, Shun*; Kasagi, Jirota*; et al.

Physical Review C, 101(5), p.052201_1 - 052201_6, 2020/05

https://doi.org/10.1103/PhysRevC.101.052201

Shielding performance of newly developed boron-loaded concrete for DT neutrons

Sato, Satoshi*; Konno, Chikara; Nakashima, Hiroshi; Shionaga, Ryosuke*; Nose, Hiroyuki*; Ito, Yuji*; Hashimoto, Hirohide*

Journal of Nuclear Science and Technology, 55(4), p.410 - 417, 2018/04

https://doi.org/10.1080/00223131.2017.1403380

In order to enhance the neutron shielding performance, we developed concrete with boron of more than 10 wt%. We performed a neutron shielding experiment using the mockup of the newly developed boron-loaded concrete and DT neutrons at FNS in JAEA, and measured the reaction rates of the Nb(n,2n)Nb and Au(n,)Au reactions in the mockup. The calculations were conducted by using MCNP-5.14 and FENDL-2.1. The calculation results agreed well with the measured ones, and we confirmed that the accuracy was very good on the atomic composition data of the boron-loaded concrete and their nuclear data. In addition, we calculated effective dose rates and reaction rates of the Co(n,)Co and Eu(n,)Eu reactions in the boron-loaded concrete and other concretes. It is concluded that the boron-loaded concrete has much better shielding performance for DT neutrons than other concretes.

Detection of a gas region in a human body across a therapeutic carbon beam by measuring low-energy photons

Yamaguchi, Mitsutaka; Nagao, Yuto; Kawachi, Naoki; Sato, Takahiro; Fujimaki, Shu; Kamiya, Tomihiro; Torikai, Kota*; Shimada, Hirofumi*; Sugai, Hiroyuki*; Sakai, Makoto*; et al.

International Journal of PIXE, 26(1&2), p.61 - 72, 2016/00

https://doi.org/10.1142/S0129083516500078

no abstracts in English

Durability of triple-junction solar cell for HIHT environments, venus and mercury exploration missions

Imaizumi, Mitsuru*; Toyota, Hiroyuki*; Shimada, Takanobu*; Ogawa, Hiroyuki*; Tajima, Michio*; Hisamatsu, Tadashi*; Nakamura, Kazuyo*; Takamoto, Tatsuya*; Sato, Shinichiro; Oshima, Takeshi

Proceedings of the 8th International Workshop on Radiation Effects on Semiconductor Devices for Space Applications (RASEDA-8), p.127 - 130, 2008/12

Results of our study of effects of high-light-intensity and high-temperature conditions (HIHT) on the output performance of an InGaP/GaAs/Ge triple-junction solar cell are described herein. The HIHT conditions are adjusted for spacecraft environments expected for a Venus mission (Planet-C) and a Mercury mission (MMO) to be undertaken by the Japan Aerospace Exploration Agency (JAXA). Measurements of current-voltage characteristics under high light intensity for wide range of cell temperatures exhibit a kinked pattern at 0 current at +200C. The thermal cycle test results for bare cells with a wide temperature range show no output performance degradation. Continuous operation tests of 3J cells under HIHT conditions reveal gradual current output degradation, implying that solar panel design should address decreased output specifically.

A Modular metal-fuel fast reactor with one-loop main cooling system

Chikazawa, Yoshitaka; Okano, Yasushi; Konomura, Mamoru; Sato, Koji; Sawa, Naoki*; Sumita, Hiroyuki*; Nakanishi, Shigeyuki*; Ando, Masato*

Nuclear Technology, 159(3), p.267 - 278, 2007/09

https://doi.org/10.13182/NT07-A3875

A diversified or modular power source is attractive since it requires a low construction cost per unit and can be demonstrated in small scale experimental facilities. In this study, a new metal fuel sodium cooled reactor with 300MW electric has been developed enhancing cost reduction. And economical potential at demonstration stage with first of a kind (FOAK) is emphasized. A minimum configuration with a compact reactor vessel, a one-loop main cooling system and a simple fuel handling system is adopted enhancing cost reduction. For safety evaluation, reliability of the one-loop main cooling system has been shown by pipe-break transient analyses. Besides, construction cost of a demonstration plant with a first reactor and a small reprocessing and fuel fabrication facility is also evaluated. A major feature of the present concept is that the demonstration reactor and facilities can be directly appropriated for first commercial modules and the power plant can easily increase its capacity adding reactor and electrorefiner modules. A fast reactor cycle commercialization scenario using the present concept is thought to give low R&D or investment risk and high cost performance since the total demonstration plant cost is relatively small and the facilities are directly appropriated to commercial use.

PHITS; A Particle and heavy ion transport code system

Niita, Koji*; Sato, Tatsuhiko; Iwase, Hiroshi*; Nose, Hiroyuki*; Nakashima, Hiroshi; Sihver, L.*

Radiation Measurements, 41(9-10), p.1080 - 1090, 2006/10

https://doi.org/10.1016/j.radmeas.2006.07.013

The paper presents a summary of the recent development of the multi-purpose Monte Carlo Particle and Heavy Ion Transport code System, PHITS. In particular, we discuss in detail the development of two new models, JAM and JQMD, for high energy particle interactions, incorporated in PHITS, and show comparisons between model calculations and experiments for the validations of these models. The paper presents three applications of the code including spallation neutron source, heavy ion therapy and space radiation. The results and examples shown indicate PHITS has great ability of carrying out the radiation transport analysis of almost all particles including heavy ions within a wide energy range.

None

Hiroyuki, Mochida; Ota, Kunio; Kenji, Amano; Saegusa, Hiromitsu; Sato, Toshinori; Iwatsuki, Teruki; Tsuruta, Tadahiko

JNC TN7410 2005-001, 32 Pages, 2005/05

JNC-TN7410-2005-001.pdf:7.06MB

None

Conceptual Design Study of a Hydrogen Production Plant with a Sodium Cooled Reactor Using Membrane Reformer

Chikazawa, Yoshitaka; Hori, Toru; Konomura, Mamoru; Sato, Hiroyuki*; Uchida, Shoji*

Saikuru Kiko Giho, (22), p.19 - 25, 2004/00

https://rdreview.jaea.go.jp/gihou/pdf2/n22-03.pdf

In phase II of a feasibility study of JNC, we are finding a concept of a multi-purpose small sized reactor with various requirements, such as, economical competitiveness and safety. In the previous study, hydrogen production using hydrogen separation reformer was studied as one of promising concepts. In this study, a conceptual design study of a hydrogen and electric co-production plant has been done. The reactor thermal output is 375 MW and 25% of the thermal output is used for hydrogen production (70000 Nm/h). The hydrogen production cost is estimated 21 yen/Nm that is higher than the economical goal of 17 yen/Nm. The major reason of the high cost is the large hydrogen separation reformer because of the limit of hydrogen separation efficiency of palladium membrane. The development of a new high efficiency hydrogen separation membrane is needed.

Lifetime measurements of long-lived isomers in Gd using a total absorption detector

Asai, Masato; Hayashi, Hiroaki*; Osa, Akihiko; Sato, Tetsuya; Otokawa, Yoshinori; Nagae, Daisuke; Tsukada, Kazuaki; Miyashita, Yuji*; Ouchi, Hiroyuki*; Izumi, Sayaka*; et al.

no journal, , 

We have developed a new method to measure lifetime of long-lived isomers populated through the decay, using a total absorption detector. Using this method, we have determined lifetime of the K isomers in Gd and Gd for the first time. The short-lived neutron-rich nuclei Eu and Eu were produced and mass-separated by the on-line isotope separator (ISOL) at JAEA tandem accelerator facility. Beta- and rays emitted by the decay of Eu were total-absorbed by the detector, and all the events were recorded with time stamps. This method enabled us to determine lifetime of the isomers with more than 100-s lifetime.

Shielding experiment for new concrete with high concentration of boron by using DT neutrons, 2; Shielding experiment by using DT neutrons

Sato, Satoshi; Shionaga, Ryosuke*; Nose, Hiroyuki*; Konno, Chikara; Nakashima, Hiroshi

no journal, , 

In order to study the neutron shielding performance of the new concrete with high concentration of boron, the shielding experiment has been performed by using the DT neutron source at FNS in JAEA. The experimental mockup of the concrete with high concentration of boron was 40 cm in height, 40 cm in width and 60 cm in thickness. The distance between the DT neutron source and the mockup was 20 cm. Niobium and gold foils were inserted every 5 cm in depth along the center of the mockup. Reaction rates were measured on the Nb(n,2n)Nb and Au(n,gamma)Au reactions. A calculation with MCNP and FENDL-2.1 was done for the experiment. The calculation results agreed well with the measured ones in the both reaction rates. Another calculation was also conducted on the condition that the experimental mockup was replaced by the ordinary concrete. The reaction rate of the Au(n,gamma)Au reaction in the new concrete with high concentration of boron was about 1/40 of that in the ordinary concrete at the position of 50 cm in depth, and it was confirmed that the new concrete with high concentration of boron could reduce the neutron flux of low energy.