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Ross JS, Higginson DP, Ryutov D, Fiuza F, Hatarik R, Huntington CM, Kalantar DH, Link A, Pollock BB, Remington BA, Rinderknecht HG, Swadling GF, Turnbull DP, Weber S, Wilks S, Froula DH, Rosenberg MJ, Morita T, Sakawa Y, Takabe H, Drake RP, Kuranz C, Gregori G, Meinecke J, Levy MC, Koenig M, Spitkovsky A, Petrasso RD, Li CK, Sio H, Lahmann B, Zylstra AB, Park HS. Transition from Collisional to Collisionless Regimes in Interpenetrating Plasma Flows on the National Ignition Facility. PHYSICAL REVIEW LETTERS 2017; 118:185003. [PMID: 28524679 DOI: 10.1103/physrevlett.118.185003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Indexed: 06/07/2023]
Abstract
A study of the transition from collisional to collisionless plasma flows has been carried out at the National Ignition Facility using high Mach number (M>4) counterstreaming plasmas. In these experiments, CD-CD and CD-CH planar foils separated by 6-10 mm are irradiated with laser energies of 250 kJ per foil, generating ∼1000 km/s plasma flows. Varying the foil separation distance scales the ion density and average bulk velocity and, therefore, the ion-ion Coulomb mean free path, at the interaction region at the midplane. The characteristics of the flow interaction have been inferred from the neutrons and protons generated by deuteron-deuteron interactions and by x-ray emission from the hot, interpenetrating, and interacting plasmas. A localized burst of neutrons and bright x-ray emission near the midpoint of the counterstreaming flows was observed, suggesting strong heating and the initial stages of shock formation. As the separation of the CD-CH foils increases we observe enhanced neutron production compared to particle-in-cell simulations that include Coulomb collisions, but do not include collective collisionless plasma instabilities. The observed plasma heating and enhanced neutron production is consistent with the initial stages of collisionless shock formation, mediated by the Weibel filamentation instability.
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Affiliation(s)
- J S Ross
- Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551, USA
| | - D P Higginson
- Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551, USA
| | - D Ryutov
- Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551, USA
| | - F Fiuza
- SLAC National Accelerator Laboratory, Stanford University, Stanford, California 94305, USA
| | - R Hatarik
- Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551, USA
| | - C M Huntington
- Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551, USA
| | - D H Kalantar
- Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551, USA
| | - A Link
- Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551, USA
| | - B B Pollock
- Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551, USA
| | - B A Remington
- Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551, USA
| | - H G Rinderknecht
- Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551, USA
| | - G F Swadling
- Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551, USA
| | - D P Turnbull
- Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551, USA
| | - S Weber
- Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551, USA
| | - S Wilks
- Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551, USA
| | - D H Froula
- Laboratory for Laser Energetics, University of Rochester, 250 E. River Road, Rochester, New York 14623, USA
| | - M J Rosenberg
- Laboratory for Laser Energetics, University of Rochester, 250 E. River Road, Rochester, New York 14623, USA
| | - T Morita
- Kyushu University, 6-1 Kasuga-Koen, Kasuga, Fukuoka 816-8580, Japan
| | - Y Sakawa
- Osaka University, 1-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - H Takabe
- Osaka University, 1-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - R P Drake
- University of Michigan, Ann Arbor, Michigan 48109, USA
| | - C Kuranz
- University of Michigan, Ann Arbor, Michigan 48109, USA
| | - G Gregori
- Department of Physics, University of Oxford, Parks Road OX1 3PU, United Kingdom
| | - J Meinecke
- Department of Physics, University of Oxford, Parks Road OX1 3PU, United Kingdom
| | - M C Levy
- Department of Physics, University of Oxford, Parks Road OX1 3PU, United Kingdom
| | - M Koenig
- LULI, Ecole Polytechnique, CNRS, Universit Paris 6, 91128 Palaiseau, France
| | - A Spitkovsky
- Princeton University, Princeton, New Jersey 08544, USA
| | - R D Petrasso
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - C K Li
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - H Sio
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - B Lahmann
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - A B Zylstra
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - H-S Park
- Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551, USA
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Marcowith A, Bret A, Bykov A, Dieckman ME, Drury LO, Lembège B, Lemoine M, Morlino G, Murphy G, Pelletier G, Plotnikov I, Reville B, Riquelme M, Sironi L, Novo AS. The microphysics of collisionless shock waves. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2016; 79:046901. [PMID: 27007555 DOI: 10.1088/0034-4885/79/4/046901] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Collisionless shocks, that is shocks mediated by electromagnetic processes, are customary in space physics and in astrophysics. They are to be found in a great variety of objects and environments: magnetospheric and heliospheric shocks, supernova remnants, pulsar winds and their nebulæ, active galactic nuclei, gamma-ray bursts and clusters of galaxies shock waves. Collisionless shock microphysics enters at different stages of shock formation, shock dynamics and particle energization and/or acceleration. It turns out that the shock phenomenon is a multi-scale non-linear problem in time and space. It is complexified by the impact due to high-energy cosmic rays in astrophysical environments. This review adresses the physics of shock formation, shock dynamics and particle acceleration based on a close examination of available multi-wavelength or in situ observations, analytical and numerical developments. A particular emphasis is made on the different instabilities triggered during the shock formation and in association with particle acceleration processes with regards to the properties of the background upstream medium. It appears that among the most important parameters the background magnetic field through the magnetization and its obliquity is the dominant one. The shock velocity that can reach relativistic speeds has also a strong impact over the development of the micro-instabilities and the fate of particle acceleration. Recent developments of laboratory shock experiments has started to bring some new insights in the physics of space plasma and astrophysical shock waves. A special section is dedicated to new laser plasma experiments probing shock physics.
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Affiliation(s)
- A Marcowith
- Laboratoire Univers et Particules de Montpellier CNRS/Université de Montpellier, Place E. Bataillon, 34095 Montpellier, France
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