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Title: Anomalous heating and plasmoid formation in a driven magnetic reconnection experiment

Abstract

We present a detailed study of magnetic reconnection in a quasi-two-dimensional pulsed-power driven laboratory experiment. Oppositely directed magnetic fields (B=3 T), advected by supersonic, sub-Alfvénic carbon plasma flows (V in = 50 km/s), are brought together and mutually annihilate inside a thin current layer (δ = 0.6 mm). Temporally and spatially resolved optical diagnostics, including interferometry, Faraday rotation imaging, and Thomson scattering, allow us to determine the structure and dynamics of this layer, the nature of the inflows and outflows, and the detailed energy partition during the reconnection process. We measure high electron and ion temperatures (T e = 100 eV, T i = 600 eV), far in excess of what can be attributed to classical (Spitzer) resistive and viscous dissipation. Finally, we observe the repeated formation and ejection of plasmoids, consistent with the predictions from semicollisional plasmoid theory.

Authors:
 [1];  [1];  [1];  [2];  [3];  [1];  [1];  [1];  [1];  [1];  [1];  [1];  [1];  [1];  [4];  [5];  [6];  [7]
  1. Imperial College, London (United Kingdom)
  2. Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)
  3. PSL Reserch Univ., Paris (France)
  4. Imperial College, London (United Kingdom); Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
  5. Northwest Institute of Nuclear Technology, Xi'an (China)
  6. Xi'an Jiaotong Univ., Shaanxi (China)
  7. China Academy of Engineering Physics, Mianyang (China)
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1347671
Alternate Identifier(s):
OSTI ID: 1344617
Report Number(s):
LLNL-JRNL-704068
Journal ID: ISSN 0031-9007; PRLTAO; TRN: US1700698
Grant/Contract Number:
AC52-07NA27344; F03-02NA00057; SC-0001063
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Physical Review Letters
Additional Journal Information:
Journal Volume: 118; Journal Issue: 8; Journal ID: ISSN 0031-9007
Publisher:
American Physical Society (APS)
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; 70 PLASMA PHYSICS AND FUSION

Citation Formats

Hare, J. D., Suttle, L., Lebedev, S. V., Loureiro, N. F., Ciardi, A., Burdiak, G. C., Chittenden, J. P., Clayson, T., Garcia, C., Niasse, N., Robinson, T., Smith, R. A., Stuart, N., Suzuki-Vidal, F., Swadling, G. F., Ma, J., Wu, J., and Yang, Q. Anomalous heating and plasmoid formation in a driven magnetic reconnection experiment. United States: N. p., 2017. Web. doi:10.1103/PhysRevLett.118.085001.
Hare, J. D., Suttle, L., Lebedev, S. V., Loureiro, N. F., Ciardi, A., Burdiak, G. C., Chittenden, J. P., Clayson, T., Garcia, C., Niasse, N., Robinson, T., Smith, R. A., Stuart, N., Suzuki-Vidal, F., Swadling, G. F., Ma, J., Wu, J., & Yang, Q. Anomalous heating and plasmoid formation in a driven magnetic reconnection experiment. United States. doi:10.1103/PhysRevLett.118.085001.
Hare, J. D., Suttle, L., Lebedev, S. V., Loureiro, N. F., Ciardi, A., Burdiak, G. C., Chittenden, J. P., Clayson, T., Garcia, C., Niasse, N., Robinson, T., Smith, R. A., Stuart, N., Suzuki-Vidal, F., Swadling, G. F., Ma, J., Wu, J., and Yang, Q. Tue . "Anomalous heating and plasmoid formation in a driven magnetic reconnection experiment". United States. doi:10.1103/PhysRevLett.118.085001. https://www.osti.gov/servlets/purl/1347671.
@article{osti_1347671,
title = {Anomalous heating and plasmoid formation in a driven magnetic reconnection experiment},
author = {Hare, J. D. and Suttle, L. and Lebedev, S. V. and Loureiro, N. F. and Ciardi, A. and Burdiak, G. C. and Chittenden, J. P. and Clayson, T. and Garcia, C. and Niasse, N. and Robinson, T. and Smith, R. A. and Stuart, N. and Suzuki-Vidal, F. and Swadling, G. F. and Ma, J. and Wu, J. and Yang, Q.},
abstractNote = {We present a detailed study of magnetic reconnection in a quasi-two-dimensional pulsed-power driven laboratory experiment. Oppositely directed magnetic fields (B=3 T), advected by supersonic, sub-Alfvénic carbon plasma flows (Vin = 50 km/s), are brought together and mutually annihilate inside a thin current layer (δ = 0.6 mm). Temporally and spatially resolved optical diagnostics, including interferometry, Faraday rotation imaging, and Thomson scattering, allow us to determine the structure and dynamics of this layer, the nature of the inflows and outflows, and the detailed energy partition during the reconnection process. We measure high electron and ion temperatures (Te = 100 eV, Ti = 600 eV), far in excess of what can be attributed to classical (Spitzer) resistive and viscous dissipation. Finally, we observe the repeated formation and ejection of plasmoids, consistent with the predictions from semicollisional plasmoid theory.},
doi = {10.1103/PhysRevLett.118.085001},
journal = {Physical Review Letters},
number = 8,
volume = 118,
place = {United States},
year = {Tue Feb 21 00:00:00 EST 2017},
month = {Tue Feb 21 00:00:00 EST 2017}
}

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