Magnetic reconnection, turbulence, and collisionless shock

Hantao Ji, Russell Kulsrud, Masaaki Yamada

Research output: Contribution to journalArticlepeer-review

2 Scopus citations

Abstract

A short summary of recent progress in measuring and understanding turbulence during magnetic reconnection in laboratory plasmas is given. Magnetic reconnection is considered as a primary process to dissipate magnetic energy in laboratory and astrophysical plasmas. A central question concerns why the observed reconnection rates are much faster than predictions made by classical theories, such as the Sweet-Parker model based on MHD with classical Spitzer resistivity. Often, the local resistivity is conjectured to be enhanced by turbulence to accelerate reconnection rates either in the context of the Sweet-Parker model or by facilitating setup of the Pestchek model. Measurements at a dedicated laboratory experiment, called MRX or Magnetic Reconnection Experiment, have indicated existence of strong electromagnetic turbulence in current sheets undergoing fast reconnection. The origin of the turbulence has been identified as right-hand polarized whistler waves, propagating obliquely to the reconnecting field, with a phase velocity comparable to the relative drift velocity. These waves are consistent with an obliquely propagating electromagnetic lower-hybrid drift instability driven by drift speeds large compared to the Alfven speed in high-beta plasmas. Interestingly, this instability may explain electromagnetic turbulence also observed in collisionless shocks, which are common in energetic astrophysical phenomena.

Original languageEnglish (US)
Pages (from-to)219-226
Number of pages8
JournalAstrophysics and Space Science
Volume298
Issue number1-2
DOIs
StatePublished - Jun 2005

All Science Journal Classification (ASJC) codes

  • Astronomy and Astrophysics
  • Space and Planetary Science

Keywords

  • Collisionless shock
  • Laboratory experiment
  • Magnetic reconnection
  • Plasma instability
  • Turbulence

Fingerprint

Dive into the research topics of 'Magnetic reconnection, turbulence, and collisionless shock'. Together they form a unique fingerprint.

Cite this