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Sagisaka, Akito; Pirozhkov, A. S.; Mori, Michiaki; Yogo, Akifumi; Ogura, Koichi; Orimo, Satoshi; Nishiuchi, Mamiko; Ma, J.*; Kiriyama, Hiromitsu; Kanazawa, Shuhei; et al.
NIFS-PROC-85, p.30 - 33, 2011/02
The experiment of proton generation is performed for developing the laser-driven ion source. We observe proton signals in the laser-plasma interaction by using a thin-foil target. To get higher energy protons the size of the preformed plasma is reduced by changing the laser contrast level. In the high-contrast laser pulse case the maximum energy of the protons generated at rear side of the target increases.
Sugaya, Atsushi; Tanaka, Kenji; Akutsu, Shigeru
Proceedings of International Waste Management Symposia 2011 (WM2011) (CD-ROM), 11 Pages, 2011/02
The main component of the liquid wastes is sodium nitrate. Nitrate ion decomposition technology is under development to conserve a circumference environment of a disposal site. To investigate the methods for decomposing nitrate ion, several small-scale trials were performed using reductants and a catalyst in sodium nitrate solutions. It will be reported that the cement based encapsulation trials to immobilize the sodium carbonate based liquid waste, which was performed under non-radioactive condition at both small and full scale to investigate the optimum cement formulation.
Sagisaka, Akito; Pirozhkov, A. S.; Mori, Michiaki; Yogo, Akifumi; Ogura, Koichi; Orimo, Satoshi; Nishiuchi, Mamiko; Ma, J.*; Kiriyama, Hiromitsu; Kanazawa, Shuhei; et al.
Reza Kenkyu, 38(9), p.702 - 705, 2010/09
High-intensity laser and thin-foil interactions produce high-energy particles, hard X-ray, high-order harmonics, and terahertz (THz) radiation. A proton beam driven by a high-intensity laser has received attention as a compact ion source for medical applications. In this study we have tested simultaneous generation of protons and THz radiation from a thin-foil target. We use a Ti:sapphire laser system (J-KAREN) at JAEA. A laser beam is focused by an off-axis parabolic mirror at the thin-foil target. We observed the high-energy proton in the rear side of the target and THz radiation in the reflected direction. Next, high energy protons are observed by reducing the size of preformed plasma.
Yogo, Akifumi; Kiriyama, Hiromitsu; Mori, Michiaki; Esirkepov, T. Z.; Ogura, Koichi; Sagisaka, Akito; Orimo, Satoshi; Nishiuchi, Mamiko; Pirozhkov, A. S.; Nagatomo, Hideo*; et al.
European Physical Journal D, 55(2), p.421 - 425, 2009/11
Times Cited Count：3 Percentile：20.28(Optics)We demonstrate the laser-ion acceleration from a near-critical density plasma, when amplified spontaneous emission (ASE) was used to convert a solid foil target into the lower-density target. In this work, a direct comparison is made by changing the ASE intensity by factor 3 in order to investigate the target density-dependency of the laser-ion acceleration. The beam direction of high-energy component is successfully controlled by modifying the target density. The near-critical density plasma can be a favorable target to control the beam direction to be dependent on its energy.
Sagisaka, Akito; Daido, Hiroyuki; Pirozhkov, A. S.; Mori, Michiaki; Yogo, Akifumi; Ogura, Koichi; Orimo, Satoshi; Nishiuchi, Mamiko; Ma, J.-L.; Kiriyama, Hiromitsu; et al.
Frontiers of Optoelectronics in China, 2(3), p.299 - 303, 2009/09
High-intensity laser and thin-foil interactions produce high-energy ion, electron, hard X-ray, high-order harmonics, and terahertz (THz) radiation. We have performed the laser and thin-foil interaction experiments using a high-intensity Ti:sapphire laser. We have observed simultaneous generation of proton beam and THz radiation from a thin-foil target. Simultaneous generation of proton beam and UV harmonics is also observed.
Sagisaka, Akito; Pirozhkov, A. S.; Ma, J.-L.; Mori, Michiaki; Yogo, Akifumi; Ogura, Koichi; Orimo, Satoshi; Nishiuchi, Mamiko; Kiriyama, Hiromitsu; Kanazawa, Shuhei; et al.
Journal of Plasma and Fusion Research SERIES, Vol.8, p.464 - 467, 2009/09
We measure the UV harmonics from a thin-foil target by changing the laser pulse duration in the high-energy proton generation. The maximum proton energies are around 1 MeV. In the case of the 
500 fs, the peaks of UV harmonics up to fourth-order clearly appear. The spectra are broadened and shifted at the pulse durations of 100 fs and 30 fs.
Yogo, Akifumi; Daido, Hiroyuki; Mori, Michiaki; Kiriyama, Hiromitsu; Bulanov, S. V.; Bolton, P. R.; Esirkepov, T. Z.; Ogura, Koichi; Sagisaka, Akito; Orimo, Satoshi; et al.
Reza Kenkyu, 37(6), p.449 - 454, 2009/06
The acceleration of protons driven by a high-intensity laser is comprehensively investigated via control of the target density by using ASE just before the time of the main-laser interaction. Two cases were investigated for which the ASE intensity differed by three orders of magnitude: In the low contrast case the beam centre for higher energy protons is shifted closer to the laser-propagation direction of 45
, while the center of lower-energy beam remains near the target normal direction. Particle-in-cell simulations reveal that the characteristic proton acceleration is due to the quasistatic magnetic field on the target rear side with the magnetic pressure sustaining a charge separation electrostatic field.
Ogura, Koichi; Shizuma, Toshiyuki; Hayakawa, Takehito; Yogo, Akifumi; Nishiuchi, Mamiko; Orimo, Satoshi; Sagisaka, Akito; Pirozhkov, A. S.; Mori, Michiaki; Kiriyama, Hiromitsu; et al.
Applied Physics Express, 2(6), p.066001_1 - 066001_3, 2009/05
Times Cited Count：14 Percentile：49.68(Physics, Applied)Protons with energies up to 3.5 MeV have been generated by a 10 Hz compact laser with an intensity of about 10
W/cm
, focused on a 7.5 mm thick polyimide target. These protons were used to induce a nuclear reaction of 
B(p,n)C. A total activity of 11.1 Bq was created after 60-shot laser irradiation. The possibility of thin layer activation (TLA) using a high-intensity ultra-short pulsed laser is discussed.
Horiguchi, Kenichi; Sugaya, Atsushi; Saito, Yasuo; Tanaka, Kenji; Akutsu, Shigeru; Hirata, Toshiaki
Proceedings of 2009 International Congress on Advances in Nuclear Power Plants (ICAPP '09) (CD-ROM), p.9411_1 - 9411_9, 2009/05
The low-level radioactive Waste treatment Facility (LWTF) was constructed at the Tokai Reprocessing Plant (TRP) and cold test has been carried out since 2006. The waste which is treated in the LWTF is combustible/incombustible solid waste and liquid waste. In the LWTF, The combustible/incombustible solid waste will be incinerated. The liquid waste will be treated by the radio-nuclides removal process subsequently solidified by cement materials. This report describes the essential technologies of the LWTF and results of R&D work for the nitrate-ion decomposition technology for the liquid waste.
Mori, Michiaki; Yogo, Akifumi; Kiriyama, Hiromitsu; Nishiuchi, Mamiko; Ogura, Koichi; Orimo, Satoshi; Ma, J.*; Sagisaka, Akito; Kanazawa, Shuhei; Kondo, Shuji; et al.
IEEE Transactions on Plasma Science, 36(4), p.1872 - 1877, 2008/08
Times Cited Count：7 Percentile：28.39(Physics, Fluids & Plasmas)A dependence of cut-off proton kinetic energy on laser prepulse duration has been observed. ASE pedestal duration is controlled by a fast electro-optic pulse slicer where the risetime is estimated to be 130 ps. We demonstrate a new correlated spectral technique for determining this risetime using a stretched, frequency chirped pulse.
Kiriyama, Hiromitsu; Mori, Michiaki; Nakai, Yoshiki; Shimomura, Takuya*; Tanoue, Manabu*; Akutsu, Atsushi; Okada, Hajime; Motomura, Tomohiro*; Kondo, Shuji; Kanazawa, Shuhei; et al.
JAEA-Conf 2008-007, p.13 - 16, 2008/08
One of the main bottlenecks for the applications of ultrashort and ultrahigh-peak power lasers in high-field physics is a temporal contrast of the pulses. In ultrahigh-peak power lasers, a nanosecond background of the amplified spontaneous emission (ASE) is generated at the same time as the femtosecond pulse. This background is mostly generated in the preamplifier (regenerative, multipass amplifier). Even though the contrast level is usually in the range from 10
to 10
, this level is not sufficiently low at relativistic intensities greater than 10
W/cm to avoid unwanted pre-plasmas generation. We demonstrated a high-contrast, high-peak power laser with optical parametric chirped-pulse amplification (OPCPA). With the use of OPCPA, contrast is enhanced to better than 7
10
in a few picoseconds before the main pulse, which corresponds to an improvement of three to four orders in magnitude compared with conventional systems.
Orimo, Satoshi; Nishiuchi, Mamiko; Daido, Hiroyuki; Yogo, Akifumi; Ogura, Koichi; Sagisaka, Akito; Li, Z.*; Pirozhkov, A. S.; Mori, Michiaki; Kiriyama, Hiromitsu; et al.
Japanese Journal of Applied Physics, Part 1, 46(9A), p.5853 - 5858, 2007/09
Times Cited Count：17 Percentile：54.91(Physics, Applied)A laser-driven proton beam with a maximum energy of a few MeV is stably obtained using an ultra-short and high-intensity Titanium Sapphire laser. At the same time, keV X-ray is also generated at almost the same place where protons are emitted. Here, we show the successful demonstration of simultaneous proton and X-ray projection images of a test sample placed close to the source with a resolution of 10
m, which is determined from the source sizes. Although the experimental configuration is very simple, the simultaneity is better than a few hundreds of ps. A CR-39 track detector and imaging plate, which are placed as close as possible to the CR-39, are used as detectors of protons and X-ray. The technique is applicable to the precise observation of microstructures.
Daido, Hiroyuki; Sagisaka, Akito; Ogura, Koichi; Orimo, Satoshi; Nishiuchi, Mamiko; Mori, Michiaki; Ma, J.-L.; Pirozhkov, A. S.; Kiriyama, Hiromitsu; Kanazawa, Shuhei; et al.
Proceedings of 7th Pacific Rim Conference on Lasers and Electro-Optics (CLEO-PR 2007) (CD-ROM), p.77 - 79, 2007/00
We are developing a proton accelerator using an intense lasers with a focused intensity of 
10
W/cm. To monitor proton energy spectra as well as plasma parameters at each laser shot, we are using real time detectors. The proton energy of MeV is stably obtained for applications.
Daido, Hiroyuki; Sagisaka, Akito; Ogura, Koichi; Orimo, Satoshi; Nishiuchi, Mamiko; Yogo, Akifumi; Mori, Michiaki; Li, Z.*; Kiriyama, Hiromitsu; Kanazawa, Shuhei; et al.
X-Ray Lasers 2006; Springer Proceedings in Physics, Vol.115, p.595 - 605, 2007/00
At present, using ultra-short high intensity lasers at APRC, JAEA Kansai photon research institute, we are developing laser driven multiple quantum beams such as protons, X-rays, electrons and THz waves. These beams are perfectly synchronized with each other. The pulse duration of each beam is lass than a pico-second. They have sharp directionality with high brightness. If we properly combined these, we have new pump-probe techniques for various applications.
Kobayashi, Kentaro; Akutsu, Shigeru; Sasayama, Yasuo; Nakanishi, Masahiro; Ozone, Takashi; Tomomi, Terunuma,; Mogaki, Isao*
JNC TN8440 2005-007, 138 Pages, 2005/07
JNC-TN8440-2005-007.pdf:7.47MB
This document is announced about the task of Waste Management Section of Waste Management Division in 2003. Mainly, our tasks are fractionating, incinerating and storing low active solid waste and storing high active solid waste. In addition, we are performing required correspondence about management program of low level waste. We had treated and stored waste safely according to our plan. As a result, we have achieved following outcomes. 1. We incinerated the combustible low active solid waste that is generated by the operation of Tokai Reprocessing Plant and the recovery operation of incident at Low Active Liquid Waste Asphalt Solidification Facility. Waste of this recovery operation is stored in the 2nd Low Active Liquid Waste Asphalt Solidification Storage Facility. We incinerated 58 ton of wastes. 2. We stored low active solid waste 854 drums that accommodate 200L. According to the time of Low-Level Waste Treatment Facility completion, we will be able to avoid full of storage. 3. We stored high active solid waste of 148 drums that accommodate 200L. For the time being, there is no problem as regards the administration of storage facility. 4. We carried out the management program of low level solid waste according to plan.
Sakakibara, Tetsuro; Tsutomu, Tanabe,; Takahashi, Kuniaki; Akutsu, Shigeru; Kojima, Hiroshi; Sakashita, Akira*; Kuroda, Kazuhiko*
Proceedings of International Waste Management Symposium 2005 (WM 2005), 0 Pages, 2005/00
Focusing on the cover layer materials (as the Radon Barrier Materials), which could have the effect to restrain the radon from scattering into the air and the effect of the radiation shielding, we produced the radon barrier materials with crude bentonite on an experimental basis, using the rotary type comprehensive unit for grinding and mixing, through which we carried out the evaluation of the characteristics thereof.
Kobayashi, Kentaro; Isozaki, Koei; Akutsu, Shigeru; Nakanishi, Masahiro; Ozone, Takashi; Mogaki, Isao*; Aizawa, Shuichi*
JNC TN8440 2004-001, 151 Pages, 2004/05
JNC-TN8440-2004-001.pdf:88.84MB
This document is announced about task of Waste Management Section in the 2003 fiscal year.
; ; Akutsu, Shigeru; Nakanishi, Masahiro
Proceedings of 8th International Conference on Radioactive Waste Management and Environmental Remediation (ICEM '01) (CD-ROM), P. 57, 2001/00
None
Sumita, Junya; Sawa, Kazuhiro; Mogi, Haruyoshi; ; Kitami, Takayuki; Akutsu, Yoichi; *; *; *
JAERI-Research 99-054, p.41 - 0, 1999/09
JAERI-Research-99-054.pdf:1.19MB
no abstracts in English
Kano, Shigeki; Nakayama, Koichi; Koakutsu, Toru; *; *; *
PNC TN941 81-183, 115 Pages, 1981/09
The wear mark was observed between fuel cladding tube and adjacent wrapping wire in the fuelassembly irradiated at the "JOYO" MK-I core. It is necessitated that the formation mechanism, formation condition in the core and the effect of wear mark on the integrity of fuel cladding tube are clarified. The out-of-core sodium test was conducted at the Sodium Tachnology Section, O-arai Engineering Center, PNC, to estimate the load condition in the core and grasp the growth of wear mark. The test conditions were as follows: sodium temperature of 550C, cold trap temparatures of 120C and 150C, contact loads of 59 - 885g, sliding frequency of 1 Hz and sliding cycles of 10
, 10
and 10
. The test results obtained are as follows. (1)The wear depth linearly increases with increasing load and logarithm of sliding cycle, respectively. The growth of wear mark changes from initial wear to steady state wear. (2)The contact load between fuel cladding tube and wrapping wire in "JOYO" MK-I core is estimated as lower than 250g by the analysis using the test results, wear depth values, obtained at the present test. (3)The higher the contact load, the smoother the morphology of wear mark surface was. The increase of hardness was observed on the sliding surface, but the compositional and crystalline structure change and the crack caused by fatigue were not observed. (4)The sliding resistance between fuel cladding tube and wrapping wire incrementally increases with sliding and, there after, it is apt to be constant at ca. 510 sliding cycles. (5)There is not significant difference in the wear depth and the sliding reststance, respectively, between at cold trap temperatures of 120C and 150C. (6)The estimation of the growth of wear mark until the JOYO MK-I No.6 cycle by the present test results shows that the growth of wear depth is slight even after No.6 cycle.
