Refine your search:     
Report No.
 - 
Search Results: Records 1-20 displayed on this page of 537

Presentation/Publication Type

Initialising ...

Refine

Journal/Book Title

Initialising ...

Meeting title

Initialising ...

First Author

Initialising ...

Keyword

Initialising ...

Language

Initialising ...

Publication Year

Initialising ...

Held year of conference

Initialising ...

Save select records

JAEA Reports

Proceedings of the 16th Symposium on Advanced Photon Research; October 15-16, 2015, Kizugawa, Kyoto, Japan

Secretariat of Symposium on Advanced Photon Research

JAEA-Conf 2016-001, 53 Pages, 2016/03

JAEA-Conf-2016-001.pdf:6.17MB

The 16th Symposium on Advanced Photon Research was held at Kansai Photon Science Institute, Japan Atomic Energy Agency (JAEA-KPSI) in Kizugawa city, Kyoto on October 15 - 16, 2015. This report consists of invited and contributed papers presented at the oral and poster sessions in the Symposium.

Journal Articles

The Precise energy spectra measurement of laser-accelerated MeV/n-class high-Z ions and protons using CR-39 detectors

Kanasaki, Masato; Jinno, Satoshi*; Sakaki, Hironao; Kondo, Kiminori; Oda, Keiji*; Yamauchi, Tomoya*; Fukuda, Yuji

Plasma Physics and Controlled Fusion, 58(3), p.034013_1 - 034013_6, 2016/03

 Times Cited Count:13 Percentile:21.85(Physics, Fluids & Plasmas)

In order to understand the synergetic interplay between the Coulomb explosion of clusters and the background gas dynamics, we have conducted ion acceleration experiments using CO$$_2$$ clusters (250 nm in dia.) embedded in background H$$_2$$ gas with the J-KAREN laser (1 J, 40 fs, 10$$^{-10}$$ contrast) at JAEA-KPSI. By a careful analysis of etch pit positions on CR-39 and their structures including the etch pit growth behavior analysis with the multi-step etching technique, energy spectra for protons from the background gas and carbon/oxygen ions from the clusters are obtained separately. The maximum energies of protons and carbon/oxygen ions are determined as 1.6 MeV and 1.1 MeV/u, respectively. Based on the experimental results, the acceleration mechanism of the background gas ions induced by Coulomb explosion of clusters is discussed with the help from numerical simulations which employ a particle-in-cell (PIC) method including relaxation and ionization processes of plasma particles.

Journal Articles

Revealing the second harmonic generation in a femtosecond laser-driven cluster-based plasma by analyzing shapes of Ar XVII spectral lines

Oks, E.*; Dalimier, E.*; Faenov, A.*; Pikuz, T.*; Fukuda, Yuji; Andreev, A.*; Koga, J. K.; Sakaki, Hironao; Kotaki, Hideyuki; Pirozhkov, A. S.; et al.

Optics Express (Internet), 23(25), p.31991 - 32005, 2015/12

 Times Cited Count:5 Percentile:61.21(Optics)

We present experiments dealing with a femtosecond laser-driven cluster-based plasma, where by analyzing the nonlinear phenomenon of satellites of spectral lines of Ar XVII, we revealed the nonlinear phenomenon of the generation of the second harmonic of the laser frequency. For performing this analysis we developed new results in the theory of satellites of spectral lines. From such lineshape analysis we found, in particular, that the efficiency of converting the short (40 fs) intense (3$$times$$10$$^{18}$$ W/cm$$^2$$) incident laser light into the second harmonic was 2%. This result is in the excellent agreement with the 2-Dimensional Particle-In-Cell (2D PIC) simulation that we also performed. There is also an order of magnitude agreement between the thresholds for the SHG found from the line shape analysis and from the 2D PIC simulations.

JAEA Reports

Development of multi pass pumping module for thin disk laser material

Okada, Hajime; Maruyama, Momoko; Ochi, Yoshihiro; Nagashima, Keisuke

JAEA-Technology 2015-029, 29 Pages, 2015/11

JAEA-Technology-2015-029.pdf:11.21MB

We develop high repetitive and short pulse laser system using Yb doped laser ceramics for future laser application of generating high power tera-hertz wave for experimental proof of isotope separation and generating a Laser-Compton Scattering $$gamma$$-ray source for precise specific isotopes analysis. As these future laser applications needs very stable and high average power laser system, we develop thin disk laser system using Yb:YAG ceramics because of its large stored energy property and large thermal conductivity, which could avoid thermal induced effects and thermal fracture limitation due to large pumping power. A few hundred $$mu$$m thickness of thin disk laser material in laser amplifier needs multi pass optical components for enough absorption of pump power, the pumping profile and spot size on laser disk should be variable for required laser performance. We design multi pass pumping module for thin disk laser material which consists of commercial optical components and precise stages and also design doublet and triplet for various pumping profile and spot size, the laser oscillation power is evaluated with this pumping module.

Journal Articles

Terahertz dynamics of water before and after water shedding from reverse micelles

Murakami, Hiroshi

Journal of Molecular Liquids, 210(Part.A), p.37 - 43, 2015/10

Picosecond relaxation dynamics of water before and after water shedding from reverse micelles are studied using temperature-dependent terahertz time-domain spectroscopy measurements to clarify the confinement effect of the reverse micelle on the dynamics of water. Before water shedding, the relaxation process due to the collective motion of bulk-like water in the core of the reverse micelle exhibits a considerable slowing down in comparison with that in liquid water as the temperature decreases. This is attributed to the confinement effect of reverse micelles. Moreover, the time constant abruptly drops at the water shedding, and its temperature behavior is similar to that of liquid water afterwards. These results demonstrate that the water extracted from the reverse micelle attains the property of liquid water by reduction in the confinement imposed on the motion of the water.

Journal Articles

Polarization of amplified spontaneous emission in a plasma active medium

Kim, C. M.*; Steil, H.*; Matou$v{s}$, B.*; Nishikino, Masaharu; Hasegawa, Noboru; Kawachi, Tetsuya; Tran, K. A.*; Janulewicz, K. A.*

Physical Review A, 92(4), p.043807_1 - 043807_7, 2015/10

AA2015-0690.pdf:0.77MB

 Times Cited Count:3 Percentile:74.46(Optics)

We present polarization measurement of a Ni-like Ag X-ray laser working in the transient collisional excitation scheme. A calibrated membrane multilayer beam splitter was used to determine the energies of two mutually perpendicular polarization components (s and p components). As a result, we observed a high degree of polarization that fluctuated from shot to shot. The dominant polarization component switched from s to p when pumping was made stronger. The measurement results are discussed from the point of view of the general polarization theory and supported by a numerical simulation based on Maxwell-Bloch equations.

JAEA Reports

Proceedings of the 15th Symposium on Advanced Photon Research; November 13-14, 2014, Kizugawa, Kyoto, Japan

Secretariat of Symposium on Advanced Photon Research

JAEA-Conf 2015-001, 93 Pages, 2015/07

JAEA-Conf-2015-001.pdf:27.43MB

The 15th Symposium on Advanced Photon Research was held at Kansai Photon Science Institute, Japan Atomic Energy Agency (JAEA-KPSI) in Kizugawa city, Kyoto on November 13 - 14, 2014. This report consists of invited and contributed papers presented at the oral and poster sessions in the Symposium.

Journal Articles

Direct observation of the pulse width of an ultrashort electron beam

Kotaki, Hideyuki; Kawase, Keigo*; Hayashi, Yukio; Mori, Michiaki; Kando, Masaki; Koga, J. K.; Bulanov, S. V.

Journal of the Physical Society of Japan, 84(7), p.074501_1 - 074501_5, 2015/07

 Times Cited Count:6 Percentile:50.64(Physics, Multidisciplinary)

Journal Articles

Atomic/molecular clusters in intense laser fields

Fukuda, Yuji

Kyo Koshiba Kagaku No Tenkai CSJ Karento Rebyu, p.116 - 122, 2015/03

We review research activities concerning laser-cluster interactions and introduce laser-driven ion acceleration studies mainly focusing on that using relativistic plasmas produced from cluster targets, which are now intensively carrying out at JAEA-KPSI.

Journal Articles

Acceleration of highly charged GeV Fe ions from a low-Z substrate by intense femtosecond laser

Nishiuchi, Mamiko; Sakaki, Hironao; Esirkepov, T. Z.; Nishio, Katsuhisa; Pikuz, T.*; Faenov, A.*; Skobelev, I. Yu.*; Orlandi, R.; Sako, Hiroyuki; Pirozhkov, A. S.; et al.

Physics of Plasmas, 22(3), p.033107_1 - 033107_8, 2015/03

 Times Cited Count:54 Percentile:1.69(Physics, Fluids & Plasmas)

Almost fully stripped Fe ions accelerated up to 0.9 GeV are demonstrated with a 200 TW femtosecond high-intensity laser irradiating a micron-thick Al foil with Fe impurity on the surface. An energetic low-emittance high-density beam of heavy ions with a large charge-to-mass ratio can be obtained, which is useful for many applications, such as a compact radio isotope source in combination with conventional technology.

Journal Articles

Efficient selenium(IV) detection and removal from water by tailor-made novel conjugate adsorbent

Awual, M. R.; Hasan, M. M.*; Khaleque, M. A.*

Sensors and Actuators B; Chemical, 209, p.194 - 202, 2015/03

 Times Cited Count:146 Percentile:0.23(Chemistry, Analytical)

Journal Articles

High-contrast, high-intensity petawatt-class laser and applications

Kiriyama, Hiromitsu; Mori, Michiaki; Pirozhkov, A. S.; Ogura, Koichi; Sagisaka, Akito; Kon, Akira; Esirkepov, T. Z.; Hayashi, Yukio; Kotaki, Hideyuki; Kanasaki, Masato*; et al.

IEEE Journal of Selected Topics in Quantum Electronics, 21(1), p.1601118_1 - 1601118_18, 2015/01

 Times Cited Count:50 Percentile:3.09(Engineering, Electrical & Electronic)

This paper reviews the development of a high-contrast high-intensity petawatt-class Ti:sapphire chirped-pulse amplification (CPA) laser for research on high field science. We discuss in detail the design, performance and characterization of the laser. We also describe the on-going upgrade of the laser system and some applications for the laser in relativistic dominated laser-matter interactions.

Journal Articles

High order harmonics from relativistic electron spikes

Pirozhkov, A. S.; Kando, Masaki; Esirkepov, T. Z.; Faenov, A. Y.*; Pikuz, T. A.*; Kawachi, Tetsuya; Sagisaka, Akito; Koga, J. K.; Mori, Michiaki; Kawase, Keigo*; et al.

RAL-TR-2015-025, P. 22, 2015/00

Journal Articles

Demonstration of heat resistant fiber Bragg grating sensors based on femtosecond laser processing for vibration monitoring and temperature change

Nishimura, Akihiko; Takenaka, Yusuke*; Furuyama, Takehiro*; Shimomura, Takuya; Terada, Takaya; Daido, Hiroyuki

Journal of Laser Micro/Nanoengineering, 9(3), p.221 - 224, 2014/11

 Times Cited Count:0 Percentile:100(Nanoscience & Nanotechnology)

Heat resistant FBG sensors were developed by femtosecond laser processing to apply them to high temperature operated piping system of nuclear power plants. The FBG sensor was installed on the surface of a steel blade and a vibration test was conducted to detect the resonant vibration frequency of the vibrating blade. The FBG sensor had the heatproof performance at 600$$^{circ}$$C. A frequency stabilized sensing system using a tunable laser was tested for structural health monitoring in daily operation of nuclear power plants. The FBG sensor was installed on the surface of a steel blade for vibration induced strain measurements. Welding, brazing, soldering and noble metal powder adhesive were discussed for molding the FBG sensors.

JAEA Reports

Proceedings of the 14th Symposium on Advanced Photon Research; November 14-15, 2013, Kizugawa, Kyoto, Japan

Secretariat of Symposium on Advanced Photon Research

JAEA-Conf 2014-001, 90 Pages, 2014/09

JAEA-Conf-2014-001.pdf:39.21MB

The 14th Symposium on Advanced Photon Research was held Quantum Beam Science directorate at Kansai Photon Science Institute, Japan Atomic Energy Agency in Kizugawa-shi, Kyoto on November 14- 15, 2013. This report consists of invited and contributed papers presented at the oral and poster sessions in the Symposium.

Journal Articles

High order harmonics from relativistic electron spikes

Pirozhkov, A. S.; Kando, Masaki; Esirkepov, T. Z.; Gallegos, P.*; Ahmed, H.*; Ragozin, E. N.*; Faenov, A. Ya.*; Pikuz, T. A.*; Kawachi, Tetsuya; Sagisaka, Akito; et al.

New Journal of Physics (Internet), 16(9), p.093003_1 - 093003_30, 2014/09

 Times Cited Count:24 Percentile:18.59(Physics, Multidisciplinary)

Journal Articles

Optical frequency comb opens up highly efficient isotope separation of long-lived fission products; The Quantum walk to reduce radioactive waste

Yokoyama, Keiichi; Matsuoka, Leo*

Nippon Genshiryoku Gakkai-Shi, 56(8), p.525 - 528, 2014/08

With respect to the isotope separation of cesium, one of the long-lived fission products, the background, principle, feasibility, and research activity in Kansai Photon Science Institute are described.

Journal Articles

Ultra-short pulse, ultra-high intensity laser improvement techniques for laser-driven quantum beam science

Kiriyama, Hiromitsu; Kando, Masaki

Purazuma, Kaku Yugo Gakkai-Shi, 90(8), p.449 - 455, 2014/08

This paper reviews the development of a petawatt-class femtosecond laser for research on high field science. We discuss in detail the design, performance and characterization of the laser. We also describe the on-going upgrade of the laser system and some potential applications for the laser in relativistic dominated laser-matter interactions.

Journal Articles

New instrumentation using a heat resistant FBG sensor installed by laser cladding

Nishimura, Akihiko; Terada, Takaya; Takenaka, Yusuke*; Furuyama, Takehiro*; Shimomura, Takuya

Proceedings of 22nd International Conference on Nuclear Engineering (ICONE-22) (DVD-ROM), 6 Pages, 2014/07

Since 2007, JAEA has been developing laser based technologies of structural health monitoring. The FBG sensor made by femtosecond laser processing will be the best candidate. To make the best use of the heat resistant characteristic, the FBG sensor was embedded in metal mold by laser cladding. A groove was processed to the surface of a SUS metal plate. We used a QCW laser to weld a filler wire on the plate. A series of weld beads perfectly formed a sealing clad on the groove. Though the FBG sensor was buried tightly, no degradation on the reflection spectrum was detected after the processing. The FBG sensor could detect the vibration of the plate caused by impact shocks and audio vibration. The reflection peak of the FBG sensor under laser cladding condition was shifted to be 6 nm. We demonstrated that the corresponded temperature derive from the reflection peak shift reached 600 degrees in heat shock experiments. The installation procedure of a FBG sensor using a portable laser cladding machine was described.

Journal Articles

High power laser developments with femtosecond to nanosecond pulse durations for laser shock science and engineering

Kiriyama, Hiromitsu; Mori, Michiaki; Suzuki, Masayuki*; Daito, Izuru*; Okada, Hajime; Ochi, Yoshihiro; Tanaka, Momoko; Sato, Masatoshi*; Tamaoki, Yoshinori*; Yoshii, Takehiro*; et al.

Reza Kenkyu, 42(6), p.441 - 447, 2014/06

We describe three specific high power laser systems that are being developed in our laboratory for many applications in high field science, nonlinear optics and material processing. We report on a femtosecond petawatt-class Ti:sapphire chirped-pulse amplification laser system that can produce a pulse energy of 20 J of 40 fs pulse duration, a picosecond high intensity Yb:YAG chirped-pulse amplification laser system that can generate a pulse energy of 100 mJ of 0.5 ps pulse duration, and a nanosecond high repetition rate Nd:YAG laser system that can provide an average power of 360 W with a pulse duration of 30 ns delivered at a 1 kHz repetition rate. We discuss the basic design aspects and present the results from our experimental investigations of these laser systems.

537 (Records 1-20 displayed on this page)