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Arran C, Bradford P, Dearling A, Hicks GS, Al-Atabi S, Antonelli L, Ettlinger OC, Khan M, Read MP, Glize K, Notley M, Walsh CA, Kingham RJ, Najmudin Z, Ridgers CP, Woolsey NC. Measurement of Magnetic Cavitation Driven by Heat Flow in a Plasma. PHYSICAL REVIEW LETTERS 2023; 131:015101. [PMID: 37478421 DOI: 10.1103/physrevlett.131.015101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 03/22/2023] [Accepted: 05/17/2023] [Indexed: 07/23/2023]
Abstract
We describe the direct measurement of the expulsion of a magnetic field from a plasma driven by heat flow. Using a laser to heat a column of gas within an applied magnetic field, we isolate Nernst advection and show how it changes the field over a nanosecond timescale. Reconstruction of the magnetic field map from proton radiographs demonstrates that the field is advected by heat flow in advance of the plasma expansion with a velocity v_{N}=(6±2)×10^{5} m/s. Kinetic and extended magnetohydrodynamic simulations agree well in this regime due to the buildup of a magnetic transport barrier.
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Affiliation(s)
- C Arran
- York Plasma Institute, University of York, York YO10 5DD, United Kingdom
| | - P Bradford
- York Plasma Institute, University of York, York YO10 5DD, United Kingdom
| | - A Dearling
- York Plasma Institute, University of York, York YO10 5DD, United Kingdom
| | - G S Hicks
- The John Adams Institute for Accelerator Science, Blackett Laboratory, Imperial College London, London SW7 2BZ, United Kingdom
| | - S Al-Atabi
- The John Adams Institute for Accelerator Science, Blackett Laboratory, Imperial College London, London SW7 2BZ, United Kingdom
| | - L Antonelli
- First Light Fusion Ltd., Unit 9/10 Oxford Industrial Park, Mead Road, Yarnton, Kidlington OX5 1QU, United Kingdom
| | - O C Ettlinger
- The John Adams Institute for Accelerator Science, Blackett Laboratory, Imperial College London, London SW7 2BZ, United Kingdom
| | - M Khan
- York Plasma Institute, University of York, York YO10 5DD, United Kingdom
| | - M P Read
- First Light Fusion Ltd., Unit 9/10 Oxford Industrial Park, Mead Road, Yarnton, Kidlington OX5 1QU, United Kingdom
| | - K Glize
- Central Laser Facility, STFC Rutherford Appleton Laboratory, Harwell Campus, Didcot OX11 OQX, United Kingdom
| | - M Notley
- Central Laser Facility, STFC Rutherford Appleton Laboratory, Harwell Campus, Didcot OX11 OQX, United Kingdom
| | - C A Walsh
- Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550-9234, USA
| | - R J Kingham
- Blackett Laboratory, Imperial College London, London SW7 2BZ, United Kingdom
| | - Z Najmudin
- The John Adams Institute for Accelerator Science, Blackett Laboratory, Imperial College London, London SW7 2BZ, United Kingdom
| | - C P Ridgers
- York Plasma Institute, University of York, York YO10 5DD, United Kingdom
| | - N C Woolsey
- York Plasma Institute, University of York, York YO10 5DD, United Kingdom
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Ridgers CP, Arran C, Bissell JJ, Kingham RJ. The inadequacy of a magnetohydrodynamic approach to the Biermann battery. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2021; 379:20200017. [PMID: 33280564 PMCID: PMC7741009 DOI: 10.1098/rsta.2020.0017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Accepted: 08/29/2020] [Indexed: 06/12/2023]
Abstract
Magnetic fields can be generated in plasmas by the Biermann battery when the electric field produced by the electron pressure gradient has a curl. The commonly employed magnetohydrodynamic (MHD) model of the Biermann battery breaks down when the electron distribution function is distorted away from Maxwellian. Using both MHD and kinetic simulations of a laser-plasma interaction relevant to inertial confinement fusion we have shown that this distortion can reduce the Biermann-producing electric field by around 50%. More importantly, the use of a flux limiter in an MHD treatment to deal with the effect of the non-Maxwellian electron distribution on electron thermal transport leads to a completely unphysical prediction of the Biermann-producing electric field and so results in erroneous predictions for the generated magnetic field. This article is part of a discussion meeting issue 'Prospects for high gain inertial fusion energy (part 2)'.
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Affiliation(s)
- C. P. Ridgers
- York Plasma Institute, Department of Physics, University of York, Heslington, York, North Yorkshire YO10 5DD, UK
| | - C. Arran
- York Plasma Institute, Department of Physics, University of York, Heslington, York, North Yorkshire YO10 5DD, UK
| | - J. J. Bissell
- Department of Electronic Engineering, University of York, Heslington, York, North Yorkshire YO10 5DD, UK
| | - R. J. Kingham
- Blackett Laboratory, Imperial College London, Prince Consort Road, South Kensington, London SW7 2AZ, UK
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Campbell PT, Walsh CA, Russell BK, Chittenden JP, Crilly A, Fiksel G, Nilson PM, Thomas AGR, Krushelnick K, Willingale L. Magnetic Signatures of Radiation-Driven Double Ablation Fronts. PHYSICAL REVIEW LETTERS 2020; 125:145001. [PMID: 33064539 DOI: 10.1103/physrevlett.125.145001] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 08/04/2020] [Accepted: 08/10/2020] [Indexed: 06/11/2023]
Abstract
In experiments performed with the OMEGA EP laser system, magnetic field generation in double ablation fronts was observed. Proton radiography measured the strength, spatial profile, and temporal dynamics of self-generated magnetic fields as the target material was varied between plastic, aluminum, copper, and gold. Two distinct regions of magnetic field are generated in mid-Z targets-one produced by gradients from electron thermal transport and the second from radiation-driven gradients. Extended magnetohydrodynamic simulations including radiation transport reproduced key aspects of the experiment, including field generation and double ablation front formation.
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Affiliation(s)
- P T Campbell
- Gérard Mourou Center for Ultrafast Optical Science, University of Michigan, 2200 Bonisteel Boulevard, Ann Arbor, Michigan 48109, USA
| | - C A Walsh
- Blackett Laboratory, Imperial College, London SW7 2AZ, United Kingdom
| | - B K Russell
- Gérard Mourou Center for Ultrafast Optical Science, University of Michigan, 2200 Bonisteel Boulevard, Ann Arbor, Michigan 48109, USA
| | - J P Chittenden
- Blackett Laboratory, Imperial College, London SW7 2AZ, United Kingdom
| | - A Crilly
- Blackett Laboratory, Imperial College, London SW7 2AZ, United Kingdom
| | - G Fiksel
- Gérard Mourou Center for Ultrafast Optical Science, University of Michigan, 2200 Bonisteel Boulevard, Ann Arbor, Michigan 48109, USA
| | - P M Nilson
- Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623, USA
| | - A G R Thomas
- Gérard Mourou Center for Ultrafast Optical Science, University of Michigan, 2200 Bonisteel Boulevard, Ann Arbor, Michigan 48109, USA
| | - K Krushelnick
- Gérard Mourou Center for Ultrafast Optical Science, University of Michigan, 2200 Bonisteel Boulevard, Ann Arbor, Michigan 48109, USA
| | - L Willingale
- Gérard Mourou Center for Ultrafast Optical Science, University of Michigan, 2200 Bonisteel Boulevard, Ann Arbor, Michigan 48109, USA
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Liu C, Fox W, Bhattacharjee A, Thomas AGR, Joglekar AS. Momentum transport and nonlocality in heat-flux-driven magnetic reconnection in high-energy-density plasmas. Phys Rev E 2018; 96:043203. [PMID: 29347495 DOI: 10.1103/physreve.96.043203] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Indexed: 11/07/2022]
Abstract
Recent theory has demonstrated a novel physics regime for magnetic reconnection in high-energy-density plasmas where the magnetic field is advected by heat flux via the Nernst effect. Here we elucidate the physics of the electron dissipation layer in this regime. Through fully kinetic simulation and a generalized Ohm's law derived from first principles, we show that momentum transport due to a nonlocal effect, the heat-flux-viscosity, provides the dissipation mechanism for magnetic reconnection. Scaling analysis, and simulations show that the reconnection process comprises a magnetic field compression stage and quasisteady reconnection stage, and the characteristic width of the current sheet in this regime is several electron mean-free paths. These results show the important interplay between nonlocal transport effects and generation of anisotropic components to the distribution function.
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Affiliation(s)
- Chang Liu
- Department of Astrophysical Sciences, Princeton University, Princeton, New Jersey 08544, USA
| | - William Fox
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08540, USA
| | - Amitava Bhattacharjee
- Department of Astrophysical Sciences, Princeton University, Princeton, New Jersey 08544, USA.,Princeton Plasma Physics Laboratory, Princeton, New Jersey 08540, USA
| | - Alexander G R Thomas
- Department of Physics, Lancaster University, Lancaster LA1 4YB, United Kingdom.,Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Archis S Joglekar
- Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, Michigan 48109, USA.,Department of Physics and Astronomy, University of California, Los Angeles, California 90095, USA
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