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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:7 Percentile:38.91(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 (310 W/cm) 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.
Faenov, A.*; Matsubayashi, Masahito; Pikuz, T.*; Fukuda, Yuji; Kando, Masaki; Yasuda, Ryo; Iikura, Hiroshi; Nojima, Takehiro; Sakai, Takuro; Shiozawa, Masahiro*; et al.
High Power Laser Science and Engineering, 3, p.e27_1 - e27_9, 2015/10
Times Cited Count:10 Percentile:49.69(Optics)Ando, Ryosuke; Abe, Teruyoshi; Nakamura, Takahisa
E-Journal of Advanced Maintenance (Internet), 6(4), p.153 - 164, 2015/02
Wall thinning of serviced carbon steel piping of the secondary cooling system after long term operation of Advanced Thermal prototype Reactor (ATR) Fugen power station has been investigated as a series of evaluation of validity and availability of utilization of serviced materials on research projects focused on aging management. Reliability of wall thinning rates of the steel piping has been examined referring the previous inspection data. Examinations also have been made on prediction of wall thinning rates, rationalization of management of pipe wall thinning and verification of countermeasures against wall thinning.
Bulanov, S. V.; Esirkepov, T. Z.; Kando, Masaki; Koga, J. K.; Hosokai, Tomonao*; Zhidkov, A.*; Kodama, Ryosuke*
Physics of Plasmas, 20(8), p.083113_1 - 083113_10, 2013/08
Times Cited Count:19 Percentile:64.31(Physics, Fluids & Plasmas)Mizuta, Yoshio*; Hosokai, Tomonao*; Masuda, Shinichi*; Zhidkov, A.*; Makito, Keigo*; Nakanii, Nobuhiko*; Kajino, Shohei*; Nishida, Akinori*; Kando, Masaki; Mori, Michiaki; et al.
Physical Review Special Topics; Accelerators and Beams, 15(12), p.121301_1 - 121301_10, 2012/12
Times Cited Count:21 Percentile:72.39(Physics, Nuclear)Fukuda, Yuji; Faenov, A.*; Tampo, Motonobu; Pikuz, T.*; Nakamura, Tatsufumi; Kando, Masaki; Hayashi, Yukio; Yogo, Akifumi; Sakaki, Hironao; Kameshima, Takashi*; et al.
Progress in Ultrafast Intense Laser Science VII, p.225 - 240, 2011/05
We present substantial enhancement of the accelerated ion energies up to 10-20 MeV per nucleon by utilizing the unique properties of the cluster-gas target irradiated with 40-fs laser pulses of only 150 mJ energy, corresponding to approximately tenfold increase in the ion energies compared to previous experiments using thin foil targets. A particle-in-cell simulation infers that the high energy ions are generated at the rear side of the target due to the formation of a strong dipole vortex structure in sub-critical density plasmas. The demonstrated method can be important in the development of efficient laser ion accelerators for hadron therapy and other applications.
Nakamura, Tatsufumi; Tampo, Motonobu; Kodama, Ryosuke*; Bulanov, S. V.; Kando, Masaki
Physics of Plasmas, 17(11), p.113107_1 - 113107_6, 2010/11
Times Cited Count:40 Percentile:81.61(Physics, Fluids & Plasmas)Interactions of high contrast laser pulses with foam-attached targets are investigated via Particle-in-Cell (PIC) simulations in order to enhance the energy coupling from laser to plasmas. A foam layer whose mass density is much lower than that of the solid state is used for controlling the plasma density distribution of the laser irradiation region with the aid of the high contrast laser pulses. The ionization process plays a role in the laser and foam interaction, which results in the formation of periodic structure of ion charge density. The bulk electrons inside the foam layer are heated by the laser pulse, which results in the generation of abundant MeV electrons and higher energy coupling from laser to plasma. These features are utilized for laser ion acceleration by using a foam-attached thin foil target. It is shown that the laser accelerated ion energy is enhanced by properly choosing the foam parameters.
Fukuda, Yuji; Faenov, A. Y.; Tampo, Motonobu; Pikuz, T. A.*; Nakamura, Tatsufumi; Kando, Masaki; Hayashi, Yukio; Yogo, Akifumi; Sakaki, Hironao; Kameshima, Takashi*; et al.
Physical Review Letters, 103(16), p.165002_1 - 165002_4, 2009/10
Times Cited Count:162 Percentile:96.67(Physics, Multidisciplinary)A new approach for accelerating ions, based on the use of a cluster-gas target and a compact ultrashort pulse laser, is presented. It is shown that ions with energy 10-20 MeV per nucleon having a small divergence (full angle) of 3.4 are generated, corresponding to an approximately tenfold increase in the ion energies compared to previous experiments using solid targets. It is inferred from a particle-in-cell code simulation that the high energy ions are generated at the rear side of the target due to the formation of a strong dipole vortex structure in near-critical density plasmas.
Fukuda, Yuji; Faenov, A. Y.; Tampo, Motonobu; Pikuz, T. A.*; Nakamura, Tatsufumi; Kando, Masaki; Hayashi, Yukio; Yogo, Akifumi; Sakaki, Hironao; Kameshima, Takashi; et al.
AIP Conference Proceedings 1153, p.85 - 93, 2009/07
When the target consists of solid-density clusters embedded in the background gas, its irradiation by high intensity laser light renders ion acceleration a truly unique property. We present that the cluster-gas target, which consists of submicron-sized clusters and background gases, irradiated by a few TW laser pulse produces high energy ions upward of the order of 10-20 MeV/n in the forward direction.
Takamura, Shuichi*; Kado, Shinichiro*; Fujii, Takashi*; Fujiyama, Hiroshi*; Takabe, Hideaki*; Adachi, Kazuo*; Morimiya, Osamu*; Fujimori, Naoji*; Watanabe, Takayuki*; Hayashi, Yasuaki*; et al.
Kara Zukai, Purazuma Enerugi No Subete, P. 164, 2007/03
no abstracts in English
Fukuda, Yuji; Faenov, A. Y.; Tampo, Motonobu; Yogo, Akifumi; Pikuz, T. A.*; Kando, Masaki; Kotaki, Hideyuki; Daito, Izuru; Hayashi, Yukio; Kawase, Keigo; et al.
no journal, ,
A near-critical plasma cloud embedded in an underdense plasma, created by the interaction of laser prepulses with the cluster-gas target, is irradiated by the high-repetition laser pulses. Through a shadowgraphy, observed is a 3-mm long stable channel formation, from which high energy ions, accelerated up to 10 MeV/n in the laser propagation direction, are detected in a stack of plastic nuclear track detectors.
Fukuda, Yuji; Faenov, A. Y.; Tampo, Motonobu; Pikuz, T.*; Nakamura, Tatsufumi; Kando, Masaki; Hayashi, Yukio; Yogo, Akifumi; Sakaki, Hironao; Kawase, Keigo; et al.
no journal, ,
We demonstrate generation of 10-20 MeV/u ions with a compact 4 TW laser using a gas target mixed with submicron clusters, corresponding to tenfold increase in the ion energies compared to previous experiments with solid targets. It is inferred that the high energy ions are generated due to formation of a strong dipole vortex structure. The demonstrated method has a potential to construct compact and high repetition rate ion sources for hadron therapy and other applications.
Fukuda, Yuji; Faenov, A. Y.; Tampo, Motonobu; Pikuz, T. A.*; Nakamura, Tatsufumi; Kando, Masaki; Hayashi, Yukio; Homma, Takayuki; Kawase, Keigo; Yogo, Akifumi; et al.
no journal, ,
We demonstrate generation of 10-20 MeV/u ions with a compact 4 TW laser using a gas target mixed with submicron clusters, corresponding to tenfold increase in the ion energies compared to previous experiments with solid targets. It is inferred that the high energy ions are generated due to formation of a strong dipole vortex structure.
Fukuda, Yuji; Faenov, A. Y.; Tampo, Motonobu; Pikuz, T. A.*; Nakamura, Tatsufumi; Kando, Masaki; Hayashi, Yukio; Homma, Takayuki; Kawase, Keigo; Kotaki, Hideyuki; et al.
no journal, ,
An approach for accelerating ions, with the use of a cluster-gas target and an ultrashort pulse laser of 150-mJ energy and 40-fs duration, is presented. Ions with energy 10-20 MeV per nucleon having a small divergence (full angle) of 3.4 are generated in the forward direction, corresponding to approximately tenfold increase in the ion energies compared to previous experiments using solid targets. It is inferred from a particle-in-cell simulation that the high energy ions are generated at the rear side of the target due to the formation of a strong dipole vortex structure in subcritical density plasmas.
Fukuda, Yuji; Faenov, A.*; Tampo, Motonobu; Pikuz, T. A.*; Nakamura, Tatsufumi; Kando, Masaki; Hayashi, Yukio; Yogo, Akifumi; Sakaki, Hironao; Kawase, Keigo; et al.
no journal, ,
We present substantial enhancement of the accelerated ion energies up to 10-20 MeV per nucleon by utilizing the unique properties of the cluster-gas target irradiated with 40-fs laser pulses of only 150 mJ energy, corresponding to approximately tenfold increase in the ion energies compared to previous experiments using thin foil targets. A particle-in-cell simulation infers that the high energy ions are generated at the rear side of the target due to the formation of a strong dipole vortex structure in sub-critical density plasmas. The demonstrated method can be important in the development of efficient laser ion accelerators for hadron therapy and other applications.
Fukuda, Yuji; Tampo, Motonobu; Kando, Masaki; Hayashi, Yukio; Kawase, Keigo*; Faenov, A. Ya.*; Pikuz, T. A.*; Nakamura, Tatsufumi; Sakaki, Hironao; Pirozhkov, A. S.; et al.
no journal, ,
We present substantial enhancement of accelerated ion energies up to 10-20 MeV per nucleon by utilizing the unique properties of the cluster-gas target irradiated with 40-fs laser pulse of only 150 mJ energy, corresponding to approximately tenfold increase in ion energies compared to previous experiments using thin foil targets. A particle-in-cell (PIC) simulation infers that the high energy ions are generated at the rear side of the target due to the formation of a strong dipole vortex structure in sub-critical density plasmas. The latest experimental results of ion acceleration using the cluster-gas target with 40-fs laser pulses of 1-J energy will be also presented in the presentation.
Ando, Ryosuke; Abe, Teruyoshi; Nakamura, Takahisa
no journal, ,
Wall thinning of the steel piping of secondary cooling system after long term operation using the served materials of "Fugen" Power Station has been investigated as a series of the evaluation of the validity and availability of the utilization of serviced materials on the research projects focused on the aging. Reliability of the wall thinning rate of the steel piping has been examined referring the previous inspection data. Besides, prediction of the wall thinning rate, rationalization of the management of pipe wall thinning and verification of the countermeasures against wall thinning, have been also examined.
Kawachi, Tetsuya; Nishikino, Masaharu; Faenov, A.*; Pikuz, T.*; Ishino, Masahiko; Hasegawa, Noboru; Magnitskiy, S.*; Pirozhkov, A. S.; Esirkepov, T. Z.; Nishiuchi, Mamiko; et al.
no journal, ,
Laser-driven particle and radiation sources have unique and attractive characteristics such as ultra-short duration, high peak brilliance and potentials of downsizing of the source etc. Recent advent of high peak power lasers toward peta-watt (PW) level makes it possible for us to realize these particle and radiation sources with higher energy region, and now we are on the stage to investigate the mechanisms in detail and to start the applications of these novel sources. In this presentation, first of all, recent research activities in major high peak power laser facilities in Japan will be introduced, and then we will present research highlights in the last few years on the source development and the applications using high peak power lasers in Japan Atomic Energy Agency (JAEA) based upon Japan-Russia collaborations.