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Sakaki, Hironao; Nishiuchi, Mamiko; Maeda, Shota; Sagisaka, Akito; Pirozhkov, A. S.; Pikuz, T.; Faenov, A.*; Ogura, Koichi; Fukami, Tomoyo; Matsukawa, Kenya*; et al.
Review of Scientific Instruments, 85(2), p.02A705_1 - 02A705_4, 2014/02
Times Cited Count：2 Percentile：11.13(Instruments & Instrumentation)High intensity laser-plasma interaction has attracted considerable interest for a number of years. The laser-plasma interaction is accompanied by generation of various charged particle beams. Results of simultaneous novel measurements of electron-induced photonuclear neutrons (photoneutron), which are a diagnostic of the laser-plasma interaction, are proposed to use for optimization of the laser-plasma ion generation. The proposed method is demonstrated by the laser irradiation with the intensity os 1
10
W/cm
on the metal foil target. The photoneutrons are measured by using NE213 liquid scintillation detectors. Heavy-ion signal is registered with the CR39 track detector simultaneously. The measured signals of the electron-induced photoneutrons are well reproduced by using the Particle and Heavy Ion Transport code System (PHITS). The results obtained provide useful approach for analyzing the various laser based ion beams.
Yogo, Akifumi; Sato, Katsutoshi; Nishikino, Masaharu; Maeda, Takuya*; Sakaki, Hironao; Hori, Toshihiko*; Ogura, Koichi; Nishiuchi, Mamiko; Teshima, Teruki*; Nishimura, Hiroaki*; et al.
Japanese Journal of Applied Physics, 50(10), p.106401_1 - 106401_7, 2011/10
Times Cited Count：8 Percentile：34.47(Physics, Applied)Yogo, Akifumi; Maeda, Takuya; Hori, Toshihiko; Sakaki, Hironao; Ogura, Koichi; Nishiuchi, Mamiko; Sagisaka, Akito; Bolton, P.; Murakami, Masao*; Kawanishi, Shunichi; et al.
Nuclear Instruments and Methods in Physics Research A, 653(1), p.189 - 192, 2011/10
Times Cited Count：9 Percentile：56.81(Instruments & Instrumentation)Yogo, Akifumi; Maeda, Takuya*; Hori, Toshihiko*; Sakaki, Hironao; Ogura, Koichi; Nishiuchi, Mamiko; Sagisaka, Akito; Bolton, P.; Murakami, Masao*; Kawanishi, Shunichi*; et al.
Proceedings of SPIE Europe Optics + Optoelectronics 2011, Vol.8079, 8 Pages, 2011/04
Yogo, Akifumi; Maeda, Takuya; Hori, Toshihiko; Sakaki, Hironao; Ogura, Koichi; Nishiuchi, Mamiko; Sagisaka, Akito; Kiriyama, Hiromitsu; Okada, Hajime; Kanazawa, Shuhei; et al.
Applied Physics Letters, 98(5), p.053701_1 - 053701_3, 2011/02
Times Cited Count：98 Percentile：94.24(Physics, Applied)Sakaki, Hironao; Nishiuchi, Mamiko; Hori, Toshihiko; Bolton, P.; Yogo, Akifumi; Ogura, Koichi; Sagisaka, Akito; Pirozhkov, A. S.; Orimo, Satoshi; Kondo, Kiminori; et al.
Proceedings of 7th Annual Meeting of Particle Accelerator Society of Japan (DVD-ROM), p.312 - 315, 2010/08
The beam transport test is carried out through the test beam line of the laser-driven proton accelerator which consists of the phase rotation cavity, PMQ, and bending magnet. The laser system used is J-KAREN at JAEA. The final transmitted bunch duration and transverse profile are well predicted by the PARMILA particle transport code by assuming relatively low initial current of the proton beam. The most probable explanation for this is the space charge neutralization by the laser-plasma-electrons.
Nishiuchi, Mamiko; Sakaki, Hironao; Hori, Toshihiko; Bolton, P.; Ogura, Koichi; Sagisaka, Akito; Yogo, Akifumi; Mori, Michiaki; Orimo, Satoshi; Pirozhkov, A. S.; et al.
Physical Review Special Topics; Accelerators and Beams, 13(7), p.071304_1 - 071304_7, 2010/07
Times Cited Count：25 Percentile：79.26(Physics, Nuclear)A laser-driven repetition-rated 1.9 MeV proton beam line composed of permanent quadrupole magnets (PMQs), a radio frequency (rf) phase rotation cavity, and a tunable monochromator is developed to evaluate and to test the simulation of laser-accelerated proton beam transport through an integrated system for the first time. In addition, the proton spectral modulation and focusing behavior of the rf phase rotationcavity device is monitored with input from a PMQ triplet. In the 1.9 MeV region we observe very weakproton defocusing by the phase rotation cavity. The final transmitted bunch duration and transverse profile are well predicted by the PARMILA particle transport code. The transmitted proton beam duration of 6 ns corresponds to an energy spread near 5% for which the transport efficiency is simulated to be 10%. The predictive capability of PARMILA suggests that it can be useful in the design of future higher energy transport beam lines as part of an integrated laser-driven ion accelerator system.
Nishiuchi, Mamiko; Sakaki, Hironao; Hori, Toshihiko; Bolton, P.; Ogura, Koichi; Sagisaka, Akito; Yogo, Akifumi; Mori, Michiaki; Orimo, Satoshi; Pirozhkov, A. S.; et al.
Proceedings of 1st International Particle Accelerator Conference (IPAC '10) (Internet), p.88 - 90, 2010/05
The concept of a compact ion particle accelerator has become attractive in view of recent progress in laser-driven ion acceleration. We report here the recent progress in the laser-driven proton beam transport at the Photo Medical Research Center (PMRC) at JAEA, which is established to address the challenge of laser-driven ion accelerator development for ion beam cancer therapy.
Ishida, Koichi; Maeda, Shigetaka; Saikawa, Takuya*; Masui, Tomohiko*
JNC TN9400 2002-005, 68 Pages, 2002/03
JNC-TN9400-2002-005.pdf:2.14MB
It is essential to evaluate the radiation damage of core structure materials used for core support plate and reactor vessel to maintain the safe operation of nuclear reactor plant. Therefore, surveillance tests for the irradiated specimen have been conducted in the experimental fast reactor JOYO to assure the integrity and to evaluate the life time. Neutron fluence and related spectral information are key palameters in evaluation of irradiation effects on the mechanical properties. They are usually predicted based on the calculation using the DORT two-dimensional transport code. In order to evaluate the calculation accuracy, the surveillance irradiation rigs (SVIRs) with dosimeter sets and gradient-monitor to monitor neutron fluences and temperatures were loaded several positions of the JOYO MK-II core. They were irradiated between 34
and 35 cycle. Based on the verification, the JOYO neutron field was precisely characterized and the calculated neutron flux at the positions of irradiated specimen and those of the core structure components need to be evaluated were corrected based on the experiments. As a result of this study, the following items are concluded: (1)The maximum fast neutron fluence (E
0.1Mev) on surveillance test specimen is determined as 2.0710
n/cm at 9th row of the core. (2)The neutron fluences at the positions of surveillance test specimen were higher than those of the core structure components. (3)For the core support plate which seems to be most critical for JOYO life time, the fast neutron fluence at present is 9.3810
n/cm and will reach 2.3110 n/cm at the end of life. The fast neutron fluence of reactor vessel is 3.1210
n/cm at present and will reach 4.8310n/cm at the end of life.
Maeda, Shigetaka; Saikawa, Takuya*; Aoyama, Takafumi
JNC TN9410 2001-005, 219 Pages, 2001/03
JNC-TN9410-2001-005.pdf:4.92MB
Neutron fluence and related spectral information are key parameters in post-irradiation test analysis so they need to be evaluated accuracy. Nuclear calculations and a number of reactor dosimetry tests have been conducted in the JOYO experimental fast reactor to assure reliable and accurate neutron fluence for fuel and material irradiation tests. This paper describes the multiple activation foil dosimetry technique for neutron fluence evaluation. Neutron fluence was determined with neutron spectrum adjustment using measured reaction rates of a set of activation foils. Dosimetry results from individual fuel and material irradiation tests and a surveillance test characterized the neutron field of the JOYO MK-II core. Neutron flux in the JOYO core region was calculated using diffusion theory in a three-dimensional Hex-Z geometry. Flux in the stainless steel reflector region, which is outside the core, was calculated using the DORT two-dimensional transport calculation code. It is essential to correct the dosimetry results for locations far outside the core region. With corrected values, the calculated to experimental value (C/E) was approximately 1.05 in the core region and 1.1
1.5 in the reflector region.
Yogo, Akifumi; Sato, Katsutoshi; Nishikino, Masaharu; Maeda, Takuya; Nishiuchi, Mamiko; Sakaki, Hironao; Hori, Toshihiko; Mori, Michiaki; Ogura, Koichi; Orimo, Satoshi; et al.
no journal, ,
no abstracts in English
Nishiuchi, Mamiko; Sakaki, Hironao; Hori, Toshihiko; Bolton, P.; Ogura, Koichi; Yogo, Akifumi; Pirozhkov, A. S.; Sagisaka, Akito; Orimo, Satoshi; Mori, Michiaki; et al.
no journal, ,
no abstracts in English
Kiriyama, Hiromitsu; Mori, Michiaki; Shimomura, Takuya; Tanoue, Manabu; Kondo, Shuji; Kanazawa, Shuhei; Daito, Izuru; Suzuki, Masayuki*; Okada, Hajime; Ochi, Yoshihiro; et al.
no journal, ,
We describe two specific high intensity laser systems that are being developed in our laboratory for many applications such as high field science, nonlinear optics. We report on an ultra-high intensity petawatt-class Ti:sapphire chirped-pulse amplification laser system that can produce a pulse energy of 18 J with 30 fs pulse duration for studying extremely high intensity laser matter interaction process and a small-scaled Yb:YAG chirped-pulse amplification laser system that can generate a pulse energy of 100 m J of 500 fs pulse duration for compact, high efficiency, high repetition system. We discuss the basic design aspects and present the results from our experimental investigations of these laser systems.
Maeda, Shigetaka; Ito, Chikara; Aoyama, Takafumi; Saikawa, Takuya*; Masui, Tomohiko*
no journal, ,
In 2003, Joyo MK-III core was upgraded to increase the irradiation testing capability. This paper describes the details of distributions of neutron flux and reaction rate in the MK-III core that was measured by characterization tests during the first two operating cycles. The calculation accuracy of the core management codes HESTIA, TORT and MCNP, was also evaluated by the measured data. The calculated fission rates of 
U by HESTIA agreed well with the measured one within approximately 4% in the fuel region. MCNP could simulate within 6% in the central non-fuel irradiation test subassembly and the radial reflector region, while large discrepancies were obtained in TORT results. Hence, the precise geometry model was effective in evaluating the neutron spectrum and the flux at such locations.
Nishiuchi, Mamiko; Sakaki, Hironao; Sagisaka, Akito; Maeda, Shota; Pirozhkov, A. S.; Pikuz, T.; Faenov, A. Ya.*; Ogura, Koichi; Fukuda, Yuji; Matsukawa, Kenya*; et al.
no journal, ,
no abstracts in English
Maeda, Shota; Nishiuchi, Mamiko; Sakaki, Hironao; Sagisaka, Akito; Pirozhkov, A. S.; Pikuz, T.; Faenov, A. Ya.*; Ogura, Koichi; Fukuda, Yuji; Matsukawa, Kenya*; et al.
no journal, ,
In JAEA, the high energy ions generated by the interaction between Ultra-intense Ultra-Short pulse laser and thin-foil target is being studied. Irradiating condition must be optimized to generate higher energy ions while suppress the becoming gigantic of laser. It is necessary to know the physical phenomenon in plasma to determine the parameter to optimize from the information on the electron and neutron, X-rays, which are generated simultaneously with ion. In this study, in order to measure electron temperature accurately, an electron spectrometer was developed which have broad range (1-200 MeV). The detector is comprised of permanent magnets and a fluorescent plate, CCD camera. In the presentation, the result of the calibration experiment carried out using 4, 9, 12, 15 MeV quasi-monoenergetic electron beam in HIBMC will be reported. Moreover, response analysis method was inspected using PHITS which is particle transporting Monte Carlo simulation code, and will also report the result.
Bolton, P.; Abe, Mitsuyuki*; Akagi, Takashi*; Nuesslin, F.*; Hori, Toshihiko; Iwashita, Yoshihisa*; Kawanishi, Shunichi; Kondo, Kiminori; Maeda, Takuya; Molls, M.*; et al.
no journal, ,
Maeda, Takuya; Yogo, Akifumi; Demizu, Yusuke*; Hori, Toshihiko; Sakaki, Hironao; Tomoe, Yusuke*; Kondo, Kiminori; Murakami, Masao*
no journal, ,
Yogo, Akifumi; Hori, Toshihiko*; Sakaki, Hironao; Ogura, Koichi; Nishiuchi, Mamiko; Bolton, P.; Kondo, Kiminori; Maeda, Takuya*
no journal, ,
no abstracts in English
Kiriyama, Hiromitsu; Mori, Michiaki; Shimomura, Takuya; Nakai, Yoshiki*; Tanoue, Manabu*; Sasao, Hajime*; Kondo, Shuji; Kanazawa, Shuhei; Ochi, Yoshihiro; Tanaka, Momoko; et al.
no journal, ,
We report on a femtosecond high-intensity OPCPA/Ti:sapphire hybrid laser system that produces more than 30 J broadband output energy, indicating the potential for achieving petawatt-class peak powers. High temporal-contrast of 10
to 10
has been obtained with a near-perfect flat-topped spatial-profile of filling factor 80%. We also present a compact, high-intensity OPCPA/Yb:YAG hybrid laser system that generates 100 mJ output energy with a temporal contrast of better than 10
and good spatial beam quality.
