Relationship between internal stress distribution and microstructure in a suspension-sprayed thermal barrier coating with a columnar structure

Yamazaki, Yasuhiro*; Shinomiya, Keisuke*; Okumura, Tadaharu*; Suzuki, Kenji*; Shobu, Takahisa; Nakamura, Yuiga*

Quantum Beam Science (Internet), 7(2), p.14_1 - 14_12, 2023/05

https://doi.org/10.3390/qubs7020014

Experimental characterization of high-energy component in extracted pulsed neutrons at the J-PARC spallation neutron source

Harada, Masahide; Teshigawara, Makoto; Oi, Motoki; Oikawa, Kenichi; Takada, Hiroshi; Ikeda, Yujiro

Nuclear Instruments and Methods in Physics Research A, 1000, p.165252_1 - 165252_8, 2021/06

https://doi.org/10.1016/j.nima.2021.165252

This study explores high-energy neutron components of the extracted neutron beam at J-PARC pulsed neutron source using the foil activation method with threshold reactions. Foils of aluminum, gold, bismuth, niobium, and thulium were used to cover the neutron energy range from 0.3 MeV to 79.4 MeV. The experiment was performed using neutron beams of BL10 (NOBORU). The foils were irradiated by a neutron beam at 13.4 m from the moderator. To characterize high-energy neutron fields for irradiation applications, reaction rates in three different configurations with and without BC slit and Pb filter were examined. To compare the experiments with calculations given for the user, reaction rates for corresponding reactions were calculated by the PHITS code with the JENDL-3.2 and the JENDL dosimetry file. Although there was a systematic tendency in C/E (Calculation/Experiment) ratios for different threshold energies, which C/E ratio decreased as threshold energy increased up to 100 MeV, and all C/E ratios were in the range of 1.00.2. This indicated that high-energy neutron calculations were adequate for the analysis of experimental data for NOBORU users.

Unified description of the fission probability for highly excited nuclei

Iwamoto, Hiroki; Meigo, Shinichiro

Journal of Nuclear Science and Technology, 56(2), p.160 - 171, 2019/02

https://doi.org/10.1080/00223131.2018.1539351

We present a new model to describe the fission probability of the high-energy fission model, as deduced from the intranuclear cascade calculation with the Intra-Nuclear Cascade model of Lige (INCL) version 4.6 and Prokofiev's phenomenological systematics of the proton-induced fission cross sections. This model is implemented in the de-excitation model of the Generalized Evaporation Model (GEM), and applied to Monte Carlo spallation reaction simulation using the Particle and Heavy Ion Transport code System (PHITS). Comparing with experimental data for subactinide nuclei shows that this model can provide a unified prediction of the proton-, neutron-, and deuteron-induced fission cross sections with markedly improved accuracy. The calculated fission fragments tend to shift to higher mass numbers. To account for the isotopic distributions of fission fragments within the framework of a coupled INCL/GEM, modification of INCL is required, especially for description of the highly-excited states of residual nuclei.

Effect of electromagnetic pulse transverse inhomogeneity on ion acceleration by radiation pressure

Lezhnin, K.*; Kamenets, F. F.*; Beskin, V.*; Kando, Masaki; Esirkepov, T. Z.; Bulanov, S. V.

Physics of Plasmas, 22(3), p.033112_1 - 033112_9, 2015/03

https://doi.org/10.1063/1.4915136

Development of a 100eV, high-flux ion beam acceleration system

Yoshida, Hajime; Yokoyama, Kenji; Suzuki, Satoshi; Enoeda, Mikio; Akiba, Masato

Review of Scientific Instruments, 77(4), p.043502_1 - 043502_4, 2006/04

https://doi.org/10.1063/1.2188459

New beam extraction electrode has been developed for a 100 eV level, high-flux, large irradiation area, and steady-state ion beam source to study about plasma wall interaction in fusion reactors. This electrode has two specific features; one is the structure has sub-millimeter order of spherical multi-aperture triode electrodes and the other is to utilize the plasma sheath for ion acceleration. Obtained ion fluxes ware from 1.51020 H/ms to 5.31020 H/ms with the energy from 28 eV/H to 102 eV/H. These values are comparable to those of conventional high flux ion source in spite of such an extremely low energy.

Nuclear technology and potential ripple effect of superconducting magnets for fusion power plant

Nishimura, Arata*; Muroga, Takeo*; Takeuchi, Takao*; Nishitani, Takeo; Morioka, Atsuhiko

Fusion Engineering and Design, 81(8-14), p.1675 - 1681, 2006/02

https://doi.org/10.1016/j.fusengdes.2005.09.007

In a fusion reactor plant, a neutral beam injector (NBI) will be operated for a long time, and it will allow neutron streaming from NBI ports to outside of the plasma vacuum vessel. It requires the superconducting magnet to develop nuclear technology to produce stable magnetic field and to reduce activation of the magnet components. In this report, the back ground of the necessity and the contents of the nuclear technology of the superconducting magnets for fusion application are discussed and some typical investigation results are presented, which are the neutron irradiation effect on NbSn wire, the development of low activation superconducting wire, and the design concept to reduce nuclear heating and nuclear transformation by streaming. In addition, recent activities in high energy particle physics are introduced and potential ripple effect of the technology of the superconducting magnets is described briefly.

Development and operation of the JAERI superconducting energy recovery linacs

Minehara, Eisuke

Nuclear Instruments and Methods in Physics Research A, 557(1), p.16 - 22, 2006/02

https://doi.org/10.1016/j.nima.2005.10.049

The JAERI FEL facility at Tokai, Ibaraki, Japan has been well known one of the two existing and operating superconducting energy recovery linacs together with one more of JLAB (Jefferson national accelerator facility) FEL facility at Newport News, Virginia, U.S.A. We have independently and successfully developed one of the most advanced and newest accelerator technologies named "superconducting energy recovery linacs (ERLs)" and the application technologies using ERLs in future. We plan to report the current high power FEL upgrade program research, stress corrosion cracking prevention technology research, large current and high brightness photoelectron gun research of negative-electron affinity (NEA) photocathode and NEA electron-excitation cathode as the most important elemental technology in realizing many powerful ERLs.

Radiation safety design for the J-PARC project

Nakashima, Hiroshi; Nakane, Yoshihiro; Masukawa, Fumihiro; Matsuda, Norihiro; Oguri, Tomomi*; Nakano, Hideo*; Sasamoto, Nobuo*; Shibata, Tokushi*; Suzuki, Takenori*; Miura, Taichi*; et al.

Radiation Protection Dosimetry, 115(1-4), p.564 - 568, 2005/12

https://doi.org/10.1093/rpd/nci237

The High Intensity Proton Accelerator Project, named as J-PARC, is in progress, aiming at studies on the latest basic science and the advancing nuclear technology. In the project, the high-energy proton accelerator complex of the world highest intensity is under construction. In order to establish a reasonable shielding design, both simplified and detailed design methods were used in the shielding design of J-PARC. This paper reviews the present status of the radiation safety design study for J-PARC.

Development of dose monitoring system applicable to various radiations with wide energy ranges

Sato, Tatsuhiko; Satoh, Daiki; Endo, Akira; Yamaguchi, Yasuhiro

Journal of Nuclear Science and Technology, 42(9), p.768 - 778, 2005/09

https://doi.org/10.3327/jnst.42.768

A new inventive radiation monitor, designated to DARWIN (Dose Assessment system applicable to various Radiations with WIde energy raNges), has been developed for monitoring doses at workspaces of high energy accelerator facilities and on ground. Characteristics of DARWIN were studied by both calculation and experiment. The calculated results indicate that DARWIN gives reasonable estimations of doses at most radiation fields. It was found from the experiment that DARWIN has an excellent property of measuring doses from all particles that significantly contribute to the background dose - photon, muon and neutron with wide energy ranges.

Structure reform and special economic zone in large helium liquifier complex for the 4th generation ERL light source

Minehara, Eisuke

Proceedings of 2nd Annual Meeting of Particle Accelerator Society of Japan and 30th Linear Accelerator Meeting in Japan, p.200 - 201, 2005/07

As the fourth generation energy recovering super-conducting linac (ERL) driven light source is planned to develop and to build as the most advanced national light source facility in Japan, this is a conceptual design work and key components developmental programs including a 200MeV prototype construction. Our existing 4K zero-boil off refrigerator cryogenic and a huge 2K liquefier facility will be combined to make a new hybrid one. Because all cryogenic devices in Japan have been seriously and unnecessarily controlled and affected their safety, maintenance, operation and construction over these several tens years, we will therefore have to cut back excess safety regulation in Japanese domestic high pressure vessel code using a structure reform and special economic zone policy.