Refine your search:     
Report No.
Search Results: Records 1-20 displayed on this page of 234

Presentation/Publication Type

Initialising ...


Journal/Book Title

Initialising ...

Meeting title

Initialising ...

First Author

Initialising ...


Initialising ...


Initialising ...

Publication Year

Initialising ...

Held year of conference

Initialising ...

Save select records

Journal Articles

Towards a novel laser-driven method of exotic nuclei extraction-acceleration for fundamental physics and technology

Nishiuchi, Mamiko*; Sakaki, Hironao*; Esirkepov, T. Zh.*; Nishio, Katsuhisa; Pikuz, T. A.*; Faenov, A. Ya.*; Skobelev, I. Yu.*; Orlandi, R.; Pirozhkov, A. S.*; Sagisaka, Akito*; et al.

Plasma Physics Reports, 42(4), p.327 - 337, 2016/04

 Times Cited Count:5 Percentile:42.53(Physics, Fluids & Plasmas)

A combination of a petawatt laser and nuclear physics techniques can crucially facilitate the measurement of exotic nuclei properties. With numerical simulations and laser-driven experiments we show prospects for the Laser-driven Exotic Nuclei extraction-acceleration method proposed in [M. Nishiuchi et al., Phys. Plasmas 22, 033107 (2015)]: a femtosecond petawatt laser, irradiating a target bombarded by an external ion beam, extracts from the target and accelerates to few GeV highly charged short-lived heavy exotic nuclei created in the target via nuclear reactions.

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:38 Percentile:1.6(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

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:40 Percentile:2.13(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

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:15 Percentile:21.56(Physics, Multidisciplinary)

Journal Articles

Prepulse and amplified spontaneous emission effects on the interaction of a petawatt class laser with thin solid targets

Esirkepov, T. Z.; Koga, J. K.; Sunahara, Atsushi*; Morita, Toshimasa; Nishikino, Masaharu; Kageyama, Kei*; Nagatomo, Hideo*; Nishihara, Katsunobu; Sagisaka, Akito; Kotaki, Hideyuki; et al.

Nuclear Instruments and Methods in Physics Research A, 745, p.150 - 163, 2014/05

 Times Cited Count:28 Percentile:2.15(Instruments & Instrumentation)

Journal Articles

Current status and future prospects of "J-KAREN"; High contrast, high intensity laser for studying relativistic laser-matter interactions

Kiriyama, Hiromitsu; Mori, Michiaki; Okada, Hajime; Shimomura, Takuya; Nakai, Yoshiki*; Tanoue, Manabu; Kondo, Shuji; Kanazawa, Shuhei; Yogo, Akifumi; Sagisaka, Akito; et al.

JPS Conference Proceedings (Internet), 1, p.015095_1 - 015095_5, 2014/03

We present the design and characterization of a high-contrast, petawatt-class Ti:sapphire chirped-pulse amplification (CPA) laser system. Two saturable absorbers and low-gain optical parametric chirped-pulse amplification (OPCPA) preamplifier in the double CPA laser chain have improved the temporal contrast to 1.4$$times$$10$$^{12}$$ on the subnanosecond time scale at 70 terawatt level. Final uncompressed broadband pulse energy is 28 J, indicating the potential for reaching peak power near 600 terawatt. We also discuss our upgrade to over petawatt level at a 0.1 Hz repetition rate briefly.

Journal Articles

Measurements of electron-induced neutrons as a tool for determination of electron temperature of fast electrons in the task of optimization laser-produced plasma ions acceleration

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:81.48(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$$times$$10$$^{21}$$ W/cm$$^{2}$$ 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.

Journal Articles

Observation of preformed plasma generated from a thin-foil target for laser-driven proton acceleration

Sagisaka, Akito; Pirozhkov, A. S.; Nishiuchi, Mamiko; Ogura, Koichi; Sakaki, Hironao; Yogo, Akifumi; Mori, Michiaki; Kiriyama, Hiromitsu; Okada, Hajime; Kanazawa, Shuhei; et al.

Reza Kenkyu, 42(2), p.160 - 162, 2014/02

High-intensity laser and thin-foil interactions produce high-energy particles, hard X-ray, high-order harmonics, and terahertz radiation. A proton beam driven by a high-intensity laser has received attention as a compact ion source for medical and other applications. We have measured the proton yield from thin-foil targets irradiated with a high-intensity Ti:sapphire laser (J-KAREN) at JAEA. The longitudinal extent of the preformed plasma protruding from the front surface of the target is reduced by decreasing the duration of the amplified spontaneous emission (ASE) before the main pulse. The maximum proton energy in the target normal direction increases when the size of the preformed plasma is controlled.

Journal Articles

Relativistic high harmonic generation in gas jet targets

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

AIP Conference Proceedings 1465, p.167 - 171, 2012/07


Journal Articles

High-order harmonics from bow wave caustics driven by a high-intensity laser

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

AIP Conference Proceedings 1465, p.172 - 180, 2012/07


The bow wave induced mechanism of high-order harmonics generation was discovered using simulations and catastrophe theory. This mechanism feasibility was successfully demonstrated in 3D and 2D PIC simulations. The mechanism and the simulations explained high-order harmonics in the XUV spectral region seen in recent experiments with terawatt lasers. Development of new XUV light and X-ray source based on the high-order harmonics generation mechanism is proposed.

Journal Articles

Proton acceleration to 40 MeV using a high intensity, high contrast optical parametric chirped-pulse amplification/Ti:sapphire hybrid laser system

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

Optics Letters, 37(14), p.2868 - 2870, 2012/07

 Times Cited Count:65 Percentile:2.65(Optics)

Using high contrast (10$$^{10}$$:1) and high intensity (10$$^{21}$$ W/cm$$^{2}$$) laser pulse with the duration of 40 fs from OPCPA/Ti:Sapphire laser, a 40 MeV proton bunch is obtained, which is a record for laser pulse with energy less than 10 J. The efficiency for generation of protons with kinetic energy above 15 MeV is 0.1%.

Journal Articles

Quantitative measurement of hard X-ray spectra for high intensity laser produced plasma

Zhang, Z.*; Nishimura, Hiroaki*; Namimoto, Takura*; Fujioka, Shinsuke*; Arikawa, Yasunobu*; Nishikino, Masaharu; Kawachi, Tetsuya; Sagisaka, Akito; Hosoda, Hirokazu*; Orimo, Satoshi; et al.

Review of Scientific Instruments, 83(5), p.053502_1 - 053502_5, 2012/05

 Times Cited Count:12 Percentile:37.9(Instruments & Instrumentation)

X-ray line spectra ranging from 17 to 77 keV were quantitatively measured with a Laue spectrometer, composed of a cylindrically curved crystal and a detector. Either a visible CCD detector coupled with a CsI phosphor screen or an imaging plate can be chosen, depending on the signal intensities and exposure times. The absolute sensitivity of the spectrometer system was calibrated using pre-characterized laser-produced X-ray sources and radioisotopes. The integrated reflectivity for the crystal is in good agreement with predictions by an open code for X-ray diffraction. The energy transfer efficiency from incident laser beams to hot electrons, as the energy transfer agency for specific X-ray line emissions, is derived as a consequence of this work.

Journal Articles

Complementary characterization of radioactivity produced by repetitive laser-driven proton beam using shot-to-shot proton spectral measurement and direct activation measurement

Ogura, Koichi; Shizuma, Toshiyuki; Hayakawa, Takehito; Yogo, Akifumi; Nishiuchi, Mamiko; Orimo, Satoshi; Sagisaka, Akito; Pirozhkov, A. S.; Mori, Michiaki; Kiriyama, Hiromitsu; et al.

Japanese Journal of Applied Physics, 51(4), p.048003_1 - 048003_2, 2012/04

 Times Cited Count:2 Percentile:87.32(Physics, Applied)

A proton beam driven by a repetitive high-intensity-laser is utilized to induce a $$^{7}$$Li(p,n)$$^{7}$$Be nuclear reaction. The total activity of $$^{7}$$Be are evaluated by two different methods. The activity obtained measuring the decay $$gamma$$-rays after 1912 shots at 1 Hz is 1.7$$pm$$0.2 Bq. This is in good agreement with 1.6$$pm$$0.3 Bq evaluated from the proton energy distribution measured using a time-of-flight detector and the nuclear reaction cross-sections. We conclude that the production of activity can be monitored in real time using the time-of-flight-detector placed inside a diverging proton beam coupled with a high-speed signal processing system.

Journal Articles

Soft-X-ray harmonic comb from relativistic electron spikes

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

Physical Review Letters, 108(13), p.135004_1 - 135004_5, 2012/03

 Times Cited Count:47 Percentile:8.78(Physics, Multidisciplinary)

We demonstrate a new high-order harmonic generation mechanism reaching the "water window" spectral region in experiments with multi-terawatt femtosecond lasers irradiating gas jets. A few hundred harmonic orders are resolved, giving $$mu$$J/sr pulses. Harmonics are collectively emitted by an oscillating electron spike formed at the joint of the boundaries of a cavity and bow wave created by a relativistically self-focusing laser in underdense plasma. The spike sharpness and stability are explained by catastrophe theory. The mechanism is corroborated by particle-in-cell simulations.

Journal Articles

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

 Times Cited Count:6 Percentile:63.68(Physics, Fluids & Plasmas)

A 7 MeV proton beam collimated to 16 mrad containing more than $$10^6$$ 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.

Journal Articles

Development of laser-driven quasi-monoenergetic proton beam line for radiobiology

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:6 Percentile:44.68(Instruments & Instrumentation)

Journal Articles

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


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$$^{11}$$ 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$$^{20}$$ Wcm$$^{-2}$$. The maximum proton energy is reached to 14 MeV. The number of $$sim$$ 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.

Journal Articles

Radiobiology with laser-accelerated quasi-monoenergetic proton beams

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

Journal Articles

Measurement of relative biological effectiveness of protons in human cancer cells using a laser-driven quasimonoenergetic proton beamline

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:60 Percentile:6.57(Physics, Applied)

234 (Records 1-20 displayed on this page)