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6 results on '"H. Shimogawara"'

1. Hydrodynamic instabilities in a highly radiative environment

Author

G. Rigon, B. Albertazzi, P. Mabey, Th. Michel, P. Barroso, A. Faenov, R. Kumar, C. Michaut, T. Pikuz, Y. Sakawa, T. Sano, H. Shimogawara, S. Tamatani, A. Casner, M. Koenig, Laboratoire pour l'utilisation des lasers intenses (LULI), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École polytechnique (X)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Nagoya University, Freie Universität Berlin, Galaxies, Etoiles, Physique, Instrumentation (GEPI), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Joint Institute for High Temperatures of the RAS (JIHT), Russian Academy of Sciences [Moscow] (RAS), Osaka University [Osaka], Joseph Louis LAGRANGE (LAGRANGE), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Centre d'études scientifiques et techniques d'Aquitaine (CESTA), Direction des Applications Militaires (DAM), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)

Subjects
Shock waves, Radiography, 500 Naturwissenschaften und Mathematik::530 Physik::539 Moderne Physik, [PHYS.PHYS.PHYS-PLASM-PH]Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph], Fluid instabilities, Lasers, Radiative gas dynamics, Flow instabilities, Astrophysics, Condensed Matter Physics, Optical imaging
Abstract

International audience; In this paper, we present the effects of a radiative shock (RS) on the morphology of jet-like objects subjected to hydrodynamic instabilities. To this end, we used an experimental platform developed to create RSs on high energy laser facilities such as LULI2000 and GEKKO XII. Here, we employed modulated targets to initiate Richtmyer–Meshkov and Rayleigh–Taylor instability (RTI) growth in the presence of an RS. The RS is obtained by generating a strong shock in a dense pusher that expands into a low-density xenon gas. With our design, only a limited RTI growth occurs in the absence of radiative effects. A strongly radiative shock has opposite effects on RTI growth. While its deceleration enhances the instability growth, the produced radiations tend to stabilize the interfaces. Our indirect experimental observations suggest a lower instability growth despite the interface deceleration. In addition, the jets, produced during the experiment, are relevant to astrophysical structures such as Herbig–Haro objects or other radiatively cooling jets.

Published
2022
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2. Laser astrophysics experiment on the amplification of magnetic fields by shock-induced interfacial instabilities

Author

Michel Koenig, Youichi Sakawa, P. Mabey, Bruno Albertazzi, Masakatsu Murakami, Takayoshi Sano, M. Ota, Seung Ho Lee, R. Kumar, S. Egashira, Kazuki Matsuo, Alexis Casner, Taichi Morita, Shohei Tamatani, Y. Hara, Keisuke Shigemori, Shinsuke Fujioka, Shohei Sakata, Thibault Michel, H. Shimogawara, G. Rigon, King Fai Farley Law, Research Applications Laboratory [Boulder] (RAL), National Center for Atmospheric Research [Boulder] (NCAR), Laboratoire pour l'utilisation des lasers intenses (LULI), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École polytechnique (X)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Centre d'Etudes Lasers Intenses et Applications (CELIA), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Bordeaux (UB), and Université de Bordeaux (UB)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
FOS: Physical sciences, 7. Clean energy, 01 natural sciences, Instability, 010305 fluids & plasmas, law.invention, law, 0103 physical sciences, 010306 general physics, ComputingMilieux_MISCELLANEOUS, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, [PHYS]Physics [physics], Turbulence, Plasma, Laser, Physics - Plasma Physics, [PHYS.PHYS.PHYS-GEN-PH]Physics [physics]/Physics [physics]/General Physics [physics.gen-ph], Shock (mechanics), Magnetic field, Computational physics, Plasma Physics (physics.plasm-ph), Interstellar medium, Supernova, 13. Climate action, Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract

Laser experiments are becoming established as a new tool for astronomical research that complements observations and theoretical modeling. Localized strong magnetic fields have been observed at a shock front of supernova explosions. Experimental confirmation and identification of the physical mechanism for this observation are of great importance in understanding the evolution of the interstellar medium. However, it has been challenging to treat the interaction between hydrodynamic instabilities and an ambient magnetic field in the laboratory. Here, we developed an experimental platform to examine magnetized Richtmyer-Meshkov instability (RMI). The measured growth velocity was consistent with the linear theory, and the magnetic-field amplification was correlated with RMI growth. Our experiment validated the turbulent amplification of magnetic fields associated with the shock-induced interfacial instability in astrophysical conditions for the first time. Experimental elucidation of fundamental processes in magnetized plasmas is generally essential in various situations such as fusion plasmas and planetary sciences., 17 pages, 12 figures, 3 tables, accepted for publication in PRE

Published
2021
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3. Spatial and temporal plasma evolutions of magnetic reconnection in laser produced plasmas

Author

Takayoshi Sano, Nima Bolouki, Toseo Moritaka, Ryo Yamazaki, Kiichiro Uchino, C. H. Chen, C. W. Peng, H. Shimogawara, Shuichi Matsukiyo, Kentaro Tomita, M. Koenig, Yuta Sato, N. Khasanah, Sara Tomita, Youichi Sakawa, T. Y. Huang, Yasuhiro Kuramitsu, Y. Hara, Y. Shoji, and S. Tomiya

Subjects
Physics, Nuclear and High Energy Physics, Framing (visual arts), Radiation, Bubble, Magnetic reconnection, Plasma, Laser, 01 natural sciences, 010305 fluids & plasmas, law.invention, Nanoflares, Optical diagnostics, Physics::Plasma Physics, law, Physics::Space Physics, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Atomic physics, 010306 general physics, Laser beams
Abstract

Magnetic reconnection is experimentally investigated in laser produced plasmas. By irradiating a solid target with a high-power laser beam, a magnetic bubble is generated due to the Biermann effect. When two laser beams with finite focal spot displacements are utilized, two magnetic bubbles are generated, and the magnetic reconnection can take place. We measure the spatial and temporal plasma evolutions with optical diagnostics using framing camera. We observed the plasma jets, which are considered to be reconnection out flows. Spatial and temporal scales of the plasma jets are much larger than those of laser. The magnetic reconnection time has been estimated from the expansion velocity, which is consistent with the Sweet-Parker model.

Published
2017
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4. Collective Thomson scattering measurements of electron feature using stimulated Brillouin scattering in laser-produced plasmas

Author

Shogo Isayama, S. Sakata, Hsu-Hsin Chu, S. Tomiya, M. Koenig, H. Shimogawara, Shinsuke Fujioka, T. Y. Huang, Y. L. Liu, C. H. Chen, C. W. Peng, Kentaro Tomita, N. Khasanah, Kiichiro Uchino, Toseo Moritaka, Yoichi Sakawa, K. Sakai, Nima Bolouki, Yuta Sato, Ryo Yamazaki, Yasuhiro Kuramitsu, Sadaoki Kojima, Y. Hara, Y. Shoji, Taichi Morita, Shuichi Matsukiyo, National Central University [Taiwan] (NCU), National Institute for Fusion Science (NIFS), Kyushu University [Fukuoka], Max-Planck-Institut für Extraterrestrische Physik (MPE), Institute of Laser Engineering (ILE), Osaka University [Osaka], Laboratoire pour l'utilisation des lasers intenses (LULI), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École polytechnique (X)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Graduate School of Engineering, Osaka University, and Kyushu University

Subjects
Nuclear and High Energy Physics, Electron density, Radiation, Drift velocity, Materials science, Thomson scattering, business.industry, Physics::Optics, Electron, Plasma, Laser, 01 natural sciences, 010305 fluids & plasmas, law.invention, Optics, Physics::Plasma Physics, Brillouin scattering, law, [PHYS.PHYS.PHYS-PLASM-PH]Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph], 0103 physical sciences, Electron temperature, 010306 general physics, business, ComputingMilieux_MISCELLANEOUS
Abstract

Collective Thomson scattering (CTS) has been applied to laser-produced plasmas with Gekko XII HIPER laser facility. A scheme of stimulated Brillouin scattering (SBS) has been used in CTS measurements for the first time. Utilizing SBS shortens the probe pulse, which increases the scattered power, and thus collected scattered signal of CTS. Therefore, a lower energy probe laser can be used for given background emission levels to avoid probe heating, which is crucial for plasmas with low electron temperature. Both electron and ion features of CTS have been successfully detected by using the SBS technique. The spatial profile of electron density, temperature, and drift velocity have been estimated in an ablation plasma. In addition to the local measurements with CTS, a global structure of plasmas has been obtained with optical imaging of the self-emission of plasmas and the interferometry. In the aspects of drift velocity and plasma density, the local and global information are in good agreement.

Published
2019
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5. Toward the Generation of Magnetized Collisionless Shocks with High-Power Lasers

Author

Toseo Moritaka, Yushiro Kawamura, Satoshi Tomiya, Sarana Kondo, H. Shimogawara, Y. Hara, Hitoki Yoneda, Sara Tomita, Naofumi Ohnishi, Ryo Yamazaki, Taichi Morita, Kentaro Tomita, Yutaka Ohira, Yasuhiro Kuramitsu, Yoshitaka Shoji, Takayuki Umeda, Takayoshi Sano, Hideaki Takabe, Shuichi Matsukiyo, Yoichi Sakawa, and Kazunori Nagamine

Subjects
Physics, Particle acceleration, Shock waves in astrophysics, 010504 meteorology & atmospheric sciences, High power lasers, 0103 physical sciences, Cosmic ray, Astrophysics, 010306 general physics, Condensed Matter Physics, 01 natural sciences, 0105 earth and related environmental sciences
Published
2016
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6. Laser astrophysics experiment on the amplification of magnetic fields by shock-induced interfacial instabilities.

Author

Sano T, Tamatani S, Matsuo K, Law KFF, Morita T, Egashira S, Ota M, Kumar R, Shimogawara H, Hara Y, Lee S, Sakata S, Rigon G, Michel T, Mabey P, Albertazzi B, Koenig M, Casner A, Shigemori K, Fujioka S, Murakami M, and Sakawa Y

Abstract

Laser experiments are becoming established as tools for astronomical research that complement observations and theoretical modeling. Localized strong magnetic fields have been observed at a shock front of supernova explosions. Experimental confirmation and identification of the physical mechanism for this observation are of great importance in understanding the evolution of the interstellar medium. However, it has been challenging to treat the interaction between hydrodynamic instabilities and an ambient magnetic field in the laboratory. Here, we developed an experimental platform to examine magnetized Richtmyer-Meshkov instability (RMI). The measured growth velocity was consistent with the linear theory, and the magnetic-field amplification was correlated with RMI growth. Our experiment validated the turbulent amplification of magnetic fields associated with the shock-induced interfacial instability in astrophysical conditions. Experimental elucidation of fundamental processes in magnetized plasmas is generally essential in various situations such as fusion plasmas and planetary sciences.

Published
2021
Full Text
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