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3. Super-ponderomotive electron acceleration in blowout plasma heated by multi-picosecond relativistic intensity laser pulse

Author

Kojima, Sadaoki, Hata, Masayasu, Iwata, Natsumi, Arikawa, Yasunobu, Morace, Alessio, Sakata, Shouhei, Lee, Seungho, Matsuo, Kazuki, Law, King Fai Farley, Morita, Hiroki, Ochiai, Yugo, Yogo, Akifumi, Nagatomo, Hideo, Ozaki, Tetsuo, Johzaki, Tomoyuki, Sunahara, Atsushi, Sakagami, Hitoshi, Zhang, Zhe, Tosaki, Shota, Abe, Yuki, Kawanaka, Junji, Tokita, Shigeki, Nakai, Mitsuo, Nishimura, Hiroaki, Shiraga, Hiroyuki, Azechi, Hiroshi, Sentoku, Yasuhiko, and Fujioka, Shinsuke

Subjects
Physics - Plasma Physics
Abstract

The dependence of the mean kinetic energy of laser-accelerated electrons on the laser intensity, so-called ponderomotive scaling, was derived theoretically with consideration of the motion of a single electron in oscillating laser fields. This scaling explains well the experimental results obtained with high-intensity pulses and durations shorter than a picosecond; however, this scaling is no longer applicable to the multi-picosecond (multi-ps) facility experiments. Here, we experimentally clarified the generation of the super-ponderomotive-relativistic electrons (SP-REs) through multi-ps relativistic laser-plasma interactions using prepulse-free LFEX laser pulses that were realized using a plasma mirror (PM). The SP-REs are produced with direct laser acceleration assisted by the self-generated quasi-static electric field and with loop-injected direct acceleration by the self- generated quasi-static magnetic field, which grow in a blowout plasma heated by a multi-ps laser pulse. Finally, we theoretically derive the threshold pulse duration to boost the acceleration of REs, which provides an important insight into the determination of laser pulse duration at kilojoule- petawatt laser facilities.

Published
2018

4. Magnetized Fast Isochoric Laser Heating for Efficient Creation of Ultra-High-Energy-Density States

Author

Sakata, Shohei, Lee, Seungho, Johzaki, Tomoyuki, Sawada, Hiroshi, Iwasa, Yuki, Morita, Hiroki, Matsuo, Kazuki, Law, King Fai Farley, Yao, Akira, Hata, Masayasu, Sunahara, Atsushi, Kojima, Sadaoki, Abe, Yuki, Kishimoto, Hidetaka, Syuhada, Aneez, Shiroto, Takashi, Morace, Alessio, Yogo, Akifumi, Iwata, Natsumi, Nakai, Mitsuo, Sakagami, Hitoshi, Ozaki, Tetsuo, Yamanoi, Kohei, Norimatsu, Takayoshi, Nakata, Yoshiki, Tokita, Shigeki, Miyanaga, Noriaki, Kawanaka, Junji, Shiraga, Hiroyuki, Mima, Kunioki, Nishimura, Hiroaki, Bailly-Grandvaux, Mathieu, Santos, Joao Jorge, Nagatomo, Hideo, Azechi, Hiroshi, Kodama, Ryosuke, Arikawa, Yasunobu, Sentoku, Yasuhiko, and Fujioka, Shinsuke

Subjects
Physics - Plasma Physics
Abstract

The quest for the inertial confinement fusion (ICF) ignition is a grand challenge, as exemplified by extraordinary large laser facilities. Fast isochoric heating of a pre-compressed plasma core with a high-intensity short-pulse laser is an attractive and alternative approach to create ultra-high-energy-density states like those found in ICF ignition sparks. This avoids the ignition quench caused by the hot spark mixing with the surrounding cold fuel, which is the crucial problem of the currently pursued ignition scheme. High-intensity lasers efficiently produce relativistic electron beams (REB). A part of the REB kinetic energy is deposited in the core, and then the heated region becomes the hot spark to trigger the ignition. However, only a small portion of the REB collides with the core because of its large divergence. Here we have demonstrated enhanced laser-to-core energy coupling with the magnetized fast isochoric heating. The method employs a kilo-tesla-level magnetic field that is applied to the transport region from the REB generation point to the core which results in guiding the REB along the magnetic field lines to the core. 7.7 $\pm$ 1.3 % of the maximum coupling was achieved even with a relatively small radial area density core ($\rho R$ $\sim$ 0.1 g/cm$^2$). The guided REB transport was clearly visualized in a pre-compressed core by using Cu-$K_\alpha$ imaging technique. A simplified model coupled with the comprehensive diagnostics yields 6.2\% of the coupling that agrees fairly with the measured coupling. This model also reveals that an ignition-scale areal density core ($\rho R$ $\sim$ 0.4 g/cm$^2$) leads to much higher laser-to-core coupling ($>$ 15%), this is much higher than that achieved by the current scheme.

Published
2017
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10. X-ray Astronomy in the Laboratory with a Miniature Compact Object Produced by Laser-Driven Implosion

Author

Fujioka, Shinsuke, Takabe, Hideaki, Yamamoto, Norimasa, Salzmann, David, Wang, Feilu, Nishimura, Hiroaki, Li, Yutong, Dong, Quanli, Wang, Shoujun, Zhang, Yi, Rhee, Yong-Joo, Lee, Yong-Woo, Han, Jae-Min, Tanabe, Minoru, Fujiwara, Takashi, Nakabayashi, Yuto, Zhao, Gang, Zhang, Jie, and Mima, Kunioki

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Solar and Stellar Astrophysics
Abstract

Laboratory spectroscopy of non-thermal equilibrium plasmas photoionized by intense radiation is a key to understanding compact objects, such as black holes, based on astronomical observations. This paper describes an experiment to study photoionizing plasmas in laboratory under well-defined and genuine conditions. Photoionized plasma is here generated using a 0.5-keV Planckian x-ray source created by means of a laser-driven implosion. The measured x-ray spectrum from the photoionized silicon plasma resembles those observed from the binary stars Cygnus X-3 and Vela X-1 with the Chandra x-ray satellite. This demonstrates that an extreme radiation field was produced in the laboratory, however, the theoretical interpretation of the laboratory spectrum significantly contradicts the generally accepted explanations in x-ray astronomy. This model experiment offers a novel test bed for validation and verification of computational codes used in x-ray astronomy., Comment: 5 pages, 4 figures are included. This is the original submitted version of the manuscript to be published in Nature Physics

Published
2009
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11. Impact of Locoregional Therapies for Brain Lesions on Survival in Patients With Non-small Cell Lung Cancer With Multiple Extrathoracic Metastases

Author

SAKAI, KOSUKE, primary, KURAMOTO, JOJI, additional, TAKAHASHI, TOMOYUKI, additional, KAWANO, YUICHIRO, additional, NISHIMURA, HIROAKI, additional, KUWABARA, YOSHIKI, additional, KOJIMA, AKITOSHI, additional, SASAKI-TODA, MAIKO, additional, OGAWA-KOBAYASHI, YUMIKO, additional, KIKUCHI, SATOSHI, additional, HIRATA, YUSUKE, additional, MIKAMI-SAITO, YURIKO, additional, MIKAMI, SHINTARO, additional, KYOYAMA, HIROYUKI, additional, MORIYAMA, GAKU, additional, KOYAMA, NOBUYUKI, additional, and UEMATSU, KAZUTSUGU, additional

Published
2023
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13. Dense Matter States Produced by Laser Pulses

Author

Nishimura, Hiroaki, Batani, Dimitri, Castleman, Albert W, Series editor, Toennies, Jan Peter, Series editor, Yamanouchi, Kaoru, Series editor, Zinth, Wolfgang, Series editor, Roso, Luis, editor, Li, Ruxin, editor, Mathur, Deepak, editor, and Normand, Didier, editor

Published
2015
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15. Electromagnetic field growth triggering super-ponderomotive electron acceleration during multi-picosecond laser-plasma interaction

Author

Kojima, Sadaoki, Hata, Masayasu, Iwata, Natsumi, Arikawa, Yasunobu, Morace, Alessio, Sakata, Shohei, Lee, Seungho, Matsuo, Kazuki, Law, King Fai Farley, Morita, Hiroki, Ochiai, Yugo, Yogo, Akifumi, Nagatomo, Hideo, Ozaki, Tetsuo, Johzaki, Tomoyuki, Sunahara, Atsushi, Sakagami, Hitoshi, Zhang, Zhe, Tosaki, Shota, Abe, Yuki, Kawanaka, Junji, Tokita, Shigeki, Nakai, Mitsuo, Nishimura, Hiroaki, Shiraga, Hiroyuki, Azechi, Hiroshi, Sentoku, Yasuhiko, and Fujioka, Shinsuke

Published
2019
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16. Demonstration of efficient relativistic electron acceleration by surface plasmonics with sequential target processing using high repetition lasers

Author

Arikawa, Yasunobu, primary, Morace, Alessio, additional, Abe, Yuki, additional, Iwata, Natsumi, additional, Sentoku, Yasuhiko, additional, Yogo, Akifumi, additional, Matsuo, Kazuki, additional, Nakai, Mitsuo, additional, Nagatomo, Hideo, additional, Mima, Kunioki, additional, Nishimura, Hiroaki, additional, Fujioka, Shinsuke, additional, Kodama, Ryosuke, additional, Inoue, Shunsuke, additional, Hashida, Masaki, additional, Sakabe, Shuji, additional, De Luis, Diego, additional, Gatti, Giancarlo, additional, Huault, Marine, additional, Pérez-Hernández, José Antonio, additional, Roso, Luis, additional, and Volpe, Luca, additional

Published
2023
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17. Feasibility study of laser-driven neutron sources for pharmaceutical applications

Author

Mori, Takato, primary, Yogo, Akifumi, additional, Arikawa, Yasunobu, additional, Hayakawa, Takehito, additional, Mirfayzi, Seyed R., additional, Lan, Zechen, additional, Wei, Tianyun, additional, Abe, Yuki, additional, Nakai, Mitsuo, additional, Mima, Kunioki, additional, Nishimura, Hiroaki, additional, Fujioka, Shinsuke, additional, and Kodama, Ryosuke, additional

Published
2023
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21. Magnetized fast isochoric laser heating for efficient creation of ultra-high-energy-density states

Author

Sakata, Shohei, Lee, Seungho, Morita, Hiroki, Johzaki, Tomoyuki, Sawada, Hiroshi, Iwasa, Yuki, Matsuo, Kazuki, Law, King Fai Farley, Yao, Akira, Hata, Masayasu, Sunahara, Atsushi, Kojima, Sadaoki, Abe, Yuki, Kishimoto, Hidetaka, Syuhada, Aneez, Shiroto, Takashi, Morace, Alessio, Yogo, Akifumi, Iwata, Natsumi, Nakai, Mitsuo, Sakagami, Hitoshi, Ozaki, Tetsuo, Yamanoi, Kohei, Norimatsu, Takayoshi, Nakata, Yoshiki, Tokita, Shigeki, Miyanaga, Noriaki, Kawanaka, Junji, Shiraga, Hiroyuki, Mima, Kunioki, Nishimura, Hiroaki, Bailly-Grandvaux, Mathieu, Santos, João Jorge, Nagatomo, Hideo, Azechi, Hiroshi, Kodama, Ryosuke, Arikawa, Yasunobu, Sentoku, Yasuhiko, and Fujioka, Shinsuke

Published
2018
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23. Nintedanib induces gene expression changes in the lung of induced-rheumatoid arthritis–associated interstitial lung disease mice

Author

Mikami, Shintaro, primary, Miura, Yoko, additional, Kondo, Shinji, additional, Sakai, Kosuke, additional, Nishimura, Hiroaki, additional, Kyoyama, Hiroyuki, additional, Moriyama, Gaku, additional, Koyama, Nobuyuki, additional, Noguchi, Hideki, additional, Ohkubo, Hirotsugu, additional, Kanazawa, Satoshi, additional, and Uematsu, Kazutsugu, additional

Published
2022
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25. Video Motion Analysis of Cinder Models through Fall Experiment

Author

MARUYAMA, Takashi, LIU, Meizhi, SASAKI, Kansuke, INOUE, Minoru, IGUCHI, Masato, FUJITA, Eisuke, and NISHIMURA, Hiroaki

Subjects
落下試験, video motion analysis, fall experiment, 抗力係数, 519.9, drag coefficient, 噴石模型, cinder models, 動画解析
Abstract

Falling properties of cinder models, non-simple shaped objects, were measured and three-dimensional falling trajectories were obtained by using video movies. Aerodynamic characteristics of cinder models were examined by the trajectory. The falling models imitated the configuration of cinders collected at the site of the experiment, Sakurajima volcano. Two types, one with sharp edges and one without sharp edges, were selected as representatives and a sphere was selected as reference model. The results showed that the drag coefficient varied with the falling velocity becoming smaller as the velocity increased. When the models fell with terminal velocity, the drag coefficients of the cinder models without and with sharp edges were about 0.5 and 0.6, respectively. The drag coefficient of the sphere model was about 0.3.

Published
2020

26. Non-destructive inspection of water or high-pressure hydrogen gas in metal pipes by the flash of neutrons and X-rays generated by laser

Author

Wei, Tianyun, Yogo, Akifumi, Hayakawa, Takehito, Arikawa, Yasunobu, Abe, Yuki, Nakanishi, Maiko, Reza Mirfayzi, Seyed, Lan, Zechen, Mori, Takato, Mima, Kunioki, Fujioka, Shinsuke, Murakami, Masakatsu, Nakai, Mitsuo, Nishimura, Hiroaki, Kar, Satyabrata, Takehito, Hayakawa, Wei, Tianyun, Yogo, Akifumi, Hayakawa, Takehito, Arikawa, Yasunobu, Abe, Yuki, Nakanishi, Maiko, Reza Mirfayzi, Seyed, Lan, Zechen, Mori, Takato, Mima, Kunioki, Fujioka, Shinsuke, Murakami, Masakatsu, Nakai, Mitsuo, Nishimura, Hiroaki, Kar, Satyabrata, and Takehito, Hayakawa

Abstract

Low-energy neutrons in the thermal and epithermal energy regions are a powerful probe to inspect water or high pressure hydrogen gas because of their large scattering cross-sections with protons. Laser-driven neutron source, which is able to simultaneously emit different types of radiations such as X-rays, can be used for neutron and X-ray radiography in the same laser shot. In the present paper, we report the demonstration of non-destructive inspection for H2O inside of a stainless steel pipe using a laser driven thermal neutron source, where water and stainless containers are detected by neutrons and X-rays, respectively. The simulation result indicates that this method is also able to measure accurately the hydrogen density in high-pressure hydrogen gas in metal containers.

Published
2022

29. Non-destructive inspection of water or high-pressure hydrogen gas in metal pipes by the flash of neutrons and x rays generated by laser

Author

Wei, Tianyun, primary, Yogo, Akifumi, additional, Hayakawa, Takehito, additional, Arikawa, Yasunobu, additional, Abe, Yuki, additional, Nakanishi, Maiko, additional, Mirfayzi, Seyed Reza, additional, Lan, Zechen, additional, Mori, Takato, additional, Mima, Kunioki, additional, Fujioka, Shinsuke, additional, Murakami, Masakatsu, additional, Nakai, Mitsuo, additional, Nishimura, Hiroaki, additional, Kar, Satyabrata, additional, and Kodama, Ryosuke, additional

Published
2022
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30. Thermal neutron fluence measurement by Cadmium differential method at laser-driven neutron source

Author

Mori, Takato, primary, Yogo, Akifumi, additional, Hayakawa, Takehito, additional, Mirfayzi, Seyed R., additional, Lan, Zechen, additional, Wei, Tianyun, additional, Abe, Yuki, additional, Arikawa, Yasunobu, additional, Nakai, Mitsuo, additional, Mima, Kunioki, additional, Nishimura, Hiroaki, additional, Fujioka, Shinsuke, additional, and Kodama, Ryosuke, additional

Published
2022
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35. High Flux Neutrons Provided by a Laser driven Neutron Source and its Application to Nuclear Astrophysics

Author

Mori, Takato, Yogo, Akifumi, Hayakawa, Takehito, Arikawa, Yasunobu, Abe, Yuki, R. Mirfayzi, Seyed, Lan, Zechen, Wei, Tianyun, Nishimura, Hiroaki, Mima, Kunioki, Nakai, Mitsuo, Golovin, Daniil, Kodama, Ryosuke, and Takehito, Hayakawa

Subjects
Astrophysics::High Energy Astrophysical Phenomena, Nuclear Experiment
Abstract

We demonstrated that (n, 2n) and (n, gamma) reactions are induced by a high-flux pulse of fast neutrons provided from a Laser-driven Neutron Source (LDNS). Several kinds of metal targets are exposed to the fast neutrons with energies of approximately 10-20 MeV. As a result, 180Hfm,181Hf, 56Mn, 198Au, and 60Co are produced by (n, gamma) reactions. Furthermore, unstable isotopes such as 54Mn, 58Co, 175Hf, and 196Au are produced by (n, 2n) reactions. We evaluate the neutron fluence and energy spectrum using the activation method in conjunction with a time-of-flight (TOF) method., The 16th international symposium on nculei in cosmos

Published
2021

40. Single shot radiography by a bright source of laser-driven thermal neutrons and x-rays

Author

Yogo, Akifumi, primary, Mirfayzi, Seyed Reza, additional, Arikawa, Yasunobu, additional, Abe, Yuki, additional, Wei, Tianyun, additional, Mori, Takato, additional, Lan, Zechen, additional, Hoonoki, Yuki, additional, Golovin, Daniil O., additional, Koga, Keisuke, additional, Suzuki, Yosuke, additional, Kanasaki, Masato, additional, Fujioka, Shinsuke, additional, Nakai, Mitsuo, additional, Hayakawa, Takehito, additional, Mima, Kunioki, additional, Nishimura, Hiroaki, additional, Kar, Satyabrata, additional, and Kodama, Ryosuke, additional

Published
2021
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43. Initial rapidity of tumor growth as a prognostic factor for the therapeutic effect of immune-checkpoint inhibitors in patients with non-small cell lung cancer: evaluation for linear and non-linear correlation

Author

Sakai, Kosuke, primary, Kuramoto, Joji, additional, Nishimura, Hiroaki, additional, Kuwabara, Yoshiki, additional, Kojima, Akitoshi, additional, Sasaki-Toda, Maiko, additional, Ogawa-Kobayashi, Yumiko, additional, Kikuchi, Satoshi, additional, Hirata, Yusuke, additional, Mikami-Saito, Yuriko, additional, Mikami, Shintaro, additional, Kyoyama, Hiroyuki, additional, Moriyama, Gaku, additional, Gemma, Akihiko, additional, and Uematsu, Kazutsugu, additional

Published
2021
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44. Direct evaluation of high neutron density environment using (n,2n) reaction induced by laser-driven neutron source

Author

Mori, Takato, primary, Yogo, Akifumi, additional, Hayakawa, Takehito, additional, Mirfayzi, Seyed R., additional, Lan, Zechen, additional, Abe, Yuki, additional, Arikawa, Yasunobu, additional, Golovin, Daniil, additional, Wei, Tianyun, additional, Honoki, Yuki, additional, Nakai, Mitsuo, additional, Mima, Kunioki, additional, Nishimura, Hiroaki, additional, Fujioka, Shinsuke, additional, and Kodama, Ryosuke, additional

Published
2021
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46. Direct evaluation of high neutron density environment using (n,2n) reaction induced by laser-driven neutron source

Author

Mori, Takato, Yogo, Akifumi, Hayakawa, Takehito, R. Mirfayzi, Seyed, Lan, Zechen, Abe, Yuki, Arikawa, Yasunobu, Golovin, Daniil, Wei, Tianyun, Honoki, Yuki, Nakai, Mitsuo, Mima, Kunioki, Nishimura, Hiroaki, Fujioka, Shinsuke, Takehito, Hayakawa, Mori, Takato, Yogo, Akifumi, Hayakawa, Takehito, R. Mirfayzi, Seyed, Lan, Zechen, Abe, Yuki, Arikawa, Yasunobu, Golovin, Daniil, Wei, Tianyun, Honoki, Yuki, Nakai, Mitsuo, Mima, Kunioki, Nishimura, Hiroaki, Fujioka, Shinsuke, and Takehito, Hayakawa

Abstract

We demonstrated that (n, 2n) and (n, gamma) reactions are induced by a high-flux pulse of fast neutrons provided from a Laser-driven Neutron Source (LDNS). The maximum energy of the broadband neutrons reaches a few tens MeV. Several kinds of metal targets are exposed to the fast neutrons. As a result, unstable isotopes such as 54Mn, 58Co, 175Hf, and 196Au are produced by (n, 2n) reactions and 180Hfm,181Hf, 56Mn, 198Au, and 60Co are produced by (n, gamma) reactions. We evaluate the neutron fluence and energy spectrum using the activation method in conjunction with a time-of-flight (TOF) method. The present scheme provides a method to evaluate high density neutrons seen in stellar environments, which are expected to be generated from future LDNSs.

Published
2021

48. Thermal neutron fluence measurement using a cadmium differential method at the laser-driven neutron source.

Author

Mori, Takato, Yogo, Akifumi, Hayakawa, Takehito, Mirfayzi, Seyed R, Lan, Zechen, Wei, Tianyun, Abe, Yuki, Arikawa, Yasunobu, Nakai, Mitsuo, Mima, Kunioki, Nishimura, Hiroaki, Fujioka, Shinsuke, and Kodama, Ryosuke

Subjects
NEUTRON measurement, NUCLEAR reactions, THERMAL neutrons, LASER-plasma interactions, CADMIUM, NEUTRON sources, NEUTRONS
Abstract

We produced high-energy neutrons by p + Be and d + Be reactions with protons and deuterons with continuous energies of up to 30 and 10 MeV/u, respectively, provided from laser-plasma interactions. Thermal neutrons were subsequently generated through deceleration by a small moderator with conjunction on the Be target. Here, we report the measurements on the thermal neutron fluence using the activation method with/without Cd filters. The unstable isotopes of 198Au, 56Mn, 60Co, and 181Hf were produced through (n, Îł) reactions by a single laser shot. The nuclear reaction fractions were evaluated by measuring the Îł -rays emitted from these unstable isotopes. The thermal neutron fluences from the four nuclides are consistent within their experimental uncertainties. The fluence is evaluated to be (2.2 ± 0.4) Ă— 105 neutrons cmâˆ'2 at the distance of approximately 9 mm at 90° against the laser axis. The present result shows that the method to generate thermal neutrons from a compact neutron source with a diameter of 44 mm and length of 46 mm is expected to be a useful tool for various nuclear experiments and applications. [ABSTRACT FROM AUTHOR]

Published
2022
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Author

MARUYAMA, Takashi, LIU, Meizhi, SASAKI, Kansuke, INOUE, Minoru, IGUCHI, Masato, FUJITA, Eisuke, NISHIMURA, Hiroaki, 60144391, MARUYAMA, Takashi, LIU, Meizhi, SASAKI, Kansuke, INOUE, Minoru, IGUCHI, Masato, FUJITA, Eisuke, NISHIMURA, Hiroaki, and 60144391

Abstract

Falling properties of cinder models, non-simple shaped objects, were measured and three-dimensional falling trajectories were obtained by using video movies. Aerodynamic characteristics of cinder models were examined by the trajectory. The falling models imitated the configuration of cinders collected at the site of the experiment, Sakurajima volcano. Two types, one with sharp edges and one without sharp edges, were selected as representatives and a sphere was selected as reference model. The results showed that the drag coefficient varied with the falling velocity becoming smaller as the velocity increased. When the models fell with terminal velocity, the drag coefficients of the cinder models without and with sharp edges were about 0.5 and 0.6, respectively. The drag coefficient of the sphere model was about 0.3.

Published
2020

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