On-site training using JMTR and related facilities in FY2016

Eguchi, Shohei; Takemoto, Noriyuki; Shibata, Hiroshi; Tanimoto, Masataka; Kusunoki, Tsuyoshi

JAEA-Review 2017-007, 32 Pages, 2017/03

JAEA-Review-2017-007.pdf:3.19MB

A practical training course using the JMTR and other research infrastructures was held from July 25th to August 5th in 2016 for domestic and foreign young researchers and engineers. This course aims to enlarge the number of high-level nuclear researchers/engineers in Japan and foreign countries which are planning to introduce a nuclear power plant, and to promote the use of facilities in future. In this year, 13 young researchers and engineers joined the course from 7 countries. This course consists of lectures, which are related to irradiation test research, safety management of nuclear reactors, nuclear characteristics of the nuclear reactors, etc., practical training and technical tour of nuclear facilities on nuclear energy. At the end of the course, the trainees discussed the energy policy and prospect of each country, each country's research reactor, and trainee's current research. The content of this course in FY 2016 is reported in this paper.

Conceptual design of multipurpose compact research reactor; Annual report FY2011

Watahiki, Shunsuke; Hanakawa, Hiroki; Imaizumi, Tomomi; Nagata, Hiroshi; Ide, Hiroshi; Komukai, Bunsaku; Kimura, Nobuaki; Miyauchi, Masaru; Ito, Masayasu; Nishikata, Kaori; et al.

JAEA-Technology 2013-021, 43 Pages, 2013/07

JAEA-Technology-2013-021.pdf:5.12MB

The number of research reactors in the world is decreasing because of their aging. On the other hand, the necessity of research reactor, which is used for human resources development, progress of the science and technology, industrial use and safety research is increasing for the countries which are planning to introduce the nuclear power plants. From above background, the Neutron Irradiation and Testing Reactor Center began to discuss a basic concept of Multipurpose Compact Research Reactor (MCRR) for education and training, etc., on 2010 to 2012. This activity is also expected to contribute to design tool improvement and human resource development in the center. In 2011, design study of reactor core, irradiation facilities with high versatility and practicality, and hot laboratory equipment for the production of Mo-99 was carried out. As the result of design study of reactor core, subcriticality and operation time of the reactor in consideration of an irradiation capsule, and about the transient response of the reactor to the reactivity disturbance during automatic control operation, it was possible to do automatic operation of MCRR, was confirmed. As the result of design study of irradiation facilities, it was confirmed that the implementation of an efficient mass production radioisotope Mo-99 can be expected. As the result of design study with hot laboratory facilities, Mo-99 production, RI export devised considered cell and facilities for exporting the specimens quickly was designed.

Quasi-monochromatic pencil beam of laser-driven protons generated using a conical cavity target holder

Nishiuchi, Mamiko; Pirozhkov, A. S.; Sakaki, Hironao; Ogura, Koichi; Esirkepov, T. Z.; Tanimoto, Tsuyoshi; Kanasaki, Masato; Yogo, Akifumi; Hori, Toshihiko; Sagisaka, Akito; et al.

Physics of Plasmas, 19(3), p.030706_1 - 030706_4, 2012/03

https://doi.org/10.1063/1.3697843

A 7 MeV proton beam collimated to 16 mrad containing more than particles is experimentally demonstrated by focusing a 2J, 60 fs pulse of a Ti:sapphire laser onto targets of different materials and thicknesses placed in a millimeter scale conical holder. The electric potential induced on the target holder by laser-driven electrons accelerates and dynamically controls a portion of a divergent quasi-thermal proton beam originated from the target, producing a quasi-monoenergetic "pencil" beam.

The Progress in the laser-driven proton acceleration experiment at JAEA with table-top Ti:Sappire laser system

Nishiuchi, Mamiko; Ogura, Koichi; Pirozhkov, A. S.; Tanimoto, Tsuyoshi; Yogo, Akifumi; Sakaki, Hironao; Hori, Toshihiko; Fukuda, Yuji; Kanasaki, Masato; Sagisaka, Akito; et al.

Proceedings of SPIE Europe Optics + Optoelectronics 2011, Vol.8079, 7 Pages, 2011/04

https://doi.org/10.1117/12.886429

Because of the peculiar characteristics of the laser-driven proton beam, many potential applications are proposed including establishing compact medical accelerator for the cancer therapy. For our final destination to establish the compact laser-driven proton accelerator, the experiments are performed to investigate proton and ion acceleration from thin foil targets, using a high contrast, ultra-short laser pulse from the J-KAREN laser at the Japan Atomic Energy Agency. The P-polarized laser pulse with the parameters of 800 nm, 40 fs, 4J, and with extremely high ASE contrast of 10 is focused onto the thin-foil targets with variable materials and thicknesses ranging from 100 um to sub-um. The achieved peak intensity is 10 Wcm. The maximum proton energy is reached to 14 MeV. The number of 10 MeV protons is enough to carry 2 Gy dose onto the skin of the mouse within 10min with 10 Hz operation. This enables us to carry out in-vivo test instead of in-vitro test.

Model experiment of cosmic ray acceleration due to an incoherent wakefield induced by an intense laser pulse

Kuramitsu, Yasuhiro*; Nakanii, Nobuhiko*; Kondo, Kiminori; Sakawa, Yoichi*; Mori, Yoshitaka*; Miura, Eisuke*; Tsuji, Kazuki*; Kimura, Kazuya*; Fukumochi, Shuji*; Kashihara, Mamoru*; et al.

Physics of Plasmas, 18(1), p.010701_1 - 010701_4, 2011/01

https://doi.org/10.1063/1.3528434

Substituting an intensive laser pulse for the large amplitude light waves, we performed a model experiment of the shock environments in a laboratory plasma. An intensive laser pulse was propagated in a plasma tube created by imploding a hollow polystyrene cylinder, as the large amplitude light waves propagated in the upstream plasma at an astrophysical shock. Nonthermal electrons were generated, and the energy distribution functions of the electrons have a power-law component with an index of 2.

Recent progress in the energy recovery linac project in Japan

Sakanaka, Shogo*; Akemoto, Mitsuo*; Aoto, Tomohiro*; Arakawa, Dai*; Asaoka, Seiji*; Enomoto, Atsushi*; Fukuda, Shigeki*; Furukawa, Kazuro*; Furuya, Takaaki*; Haga, Kaiichi*; et al.

Proceedings of 1st International Particle Accelerator Conference (IPAC '10) (Internet), p.2338 - 2340, 2010/05

http://accelconf.web.cern.ch/AccelConf/IPAC10/papers/tupe091.pdf

Future synchrotron light source using a 5-GeV energy recovery linac (ERL) is under proposal by our Japanese collaboration team, and we are conducting R&D efforts for that. We are developing high-brightness DC photocathode guns, two types of cryomodules for both injector and main superconducting (SC) linacs, and 1.3 GHz high CW-power RF sources. We are also constructing the Compact ERL (cERL) for demonstrating the recirculation of low-emittance, high-current beams using above-mentioned critical technologies.

Spectrum modulation of relativistic electrons by laser wakefield

Nakanii, Nobuhiko*; Kondo, Kiminori; Kuramitsu, Yasuhiro*; Mori, Yoshitaka*; Miura, Eisuke*; Tsuji, Kazuki*; Kimura, Kazuya*; Fukumochi, Shuji*; Kashihara, Mamoru*; Tanimoto, Tsuyoshi*; et al.

Applied Physics Letters, 93(8), p.081501_1 - 081501_3, 2008/08

https://doi.org/10.1063/1.2971235

Energetic electrons were generated by the interaction of a high-intensity laser pulse with a plasma preformed from a hollow plastic cylinder via laser-driven implosion. The spectra of a comparatively high-density plasma had a bump around 10 MeV. Simple numerical calculations explained the spectra obtained in this experiment. This indicates that the plasma tube has sufficient potential to convert a Maxwellian spectrum to a comparatively narrow spectrum.

Plasma-mirror free 40 MeV proton beam generation with ultra-high intensity high-contrast Ti:sapphire laser system

Ogura, Koichi; Nishiuchi, Mamiko; Pirozhkov, A. S.; Tanimoto, Tsuyoshi; Esirkepov, T. Z.; Sagisaka, Akito; Kando, Masaki; Shizuma, Toshiyuki; Hayakawa, Takehito; Kiriyama, Hiromitsu; et al.

no journal, , 

Without plasma mirror, the maximum proton energy of 40 MeV is obtained using a compact, high spatiotemporal-quality, high-intensity Ti:sapphire laser system with an intensity of 1E21 W/cm/cm for the first time to our knowledge.

Laser-solid target interaction at 10 W/cm intensity and 10 contrast

Pirozhkov, A. S.; Ogura, Koichi; Nishiuchi, Mamiko; Esirkepov, T. Z.; Tanimoto, Tsuyoshi*; Shimomura, Takuya; Kiriyama, Hiromitsu; Bulanov, S. V.; Kondo, Kiminori

no journal, , 

We present results of the recent experiments conducted with the J-KAREN laser at KPSI, JAEA. The laser has been carefully tuned and the solid targets aligned to provide on-target irradiance of 10 W/cm (8 J, 40 fs, 200 TW, 3 um spot). The nanosecond contrast was and the picosecond contrast has been improved by spectral phase control using high-dynamic range TG-FROG device and Dazzler. Under such conditions, we have observed integer-order and half-integer harmonics in the specular direction, which represents interest for the plasma and preplasma diagnostics relevant to the ion acceleration experiments.

Proton acceleration with the thin-foil target at KPSI

Nishiuchi, Mamiko; Ogura, Koichi; Tanimoto, Tsuyoshi*; Pirozhkov, A. S.; Sakaki, Hironao; Fukuda, Yuji; Kanasaki, Masato; Kando, Masaki; Esirkepov, T. Z.; Sagisaka, Akito*; et al.

no journal, , 

We present the extension of the maximum energy of protons from the interaction between the short-pulse compact laser system and solid thin-foil target. The laser pulses with parameters of 800 nm in wavelength, 40 fs of pulse width, 7 J of energy, 10 contrast are focused onto the target with the peak intensity of more than 10 Wcm, which is also well confirmed by the measured electron temperature of 16 MeV. We report about the acceleration mechanism as well as future prospect on the proton acceleration experiment at JAEA.