Sign on
ADS Classic is now deprecated. It will be completely retired in October 2019. This page will automatically redirect to the new ADS interface at that point.

SAO/NASA ADS Astronomy Abstract Service

· Find Similar Abstracts (with default settings below)
· Electronic Refereed Journal Article (HTML)
· Full Refereed Journal Article (PDF/Postscript)
· arXiv e-print (arXiv:1810.04135)
· References in the article
· Also-Read Articles (Reads History)
· Translate This Page
Onset of magnetic reconnection in a collisionless, high-> beta > plasma
Alt, Andrew; Kunz, Matthew W.
AA(Department of Astrophysical Sciences, Princeton University, Peyton Hall, Princeton, NJ 08544, USA), AB(Department of Astrophysical Sciences, Princeton University, Peyton Hall, Princeton, NJ 08544, USA)
Journal of Plasma Physics, Volume 85, Issue 1, article id. 764850101, 17 pp.
Publication Date:
astrophysical plasmas, plasma instabilities, plasma nonlinear phenomena
Abstract Copyright:
(c) 2019: © Cambridge University Press 2019
Bibliographic Code:


In a magnetized, collisionless plasma, the magnetic moment of the constituent particles is an adiabatic invariant. An increase in the magnetic-field strength in such a plasma thus leads to an increase in the thermal pressure perpendicular to the field lines. Above a > beta >-dependent threshold (where > beta > is the ratio of thermal to magnetic pressure), this pressure anisotropy drives the mirror instability, producing strong distortions in the field lines on ion-Larmor scales. The impact of this instability on magnetic reconnection is investigated using a simple analytical model for the formation of a current sheet (CS) and the associated production of pressure anisotropy. The difficulty in maintaining an isotropic, Maxwellian particle distribution during the formation and subsequent thinning of a CS in a collisionless plasma, coupled with the low threshold for the mirror instability in a high-> beta > plasma, imply that the geometry of reconnecting magnetic fields can differ radically from the standard Harris-sheet profile often used in simulations of collisionless reconnection. As a result, depending on the rate of CS formation and the initial CS thickness, tearing modes whose growth rates and wavenumbers are boosted by this difference may disrupt the mirror-infested CS before standard tearing modes can develop. A quantitative theory is developed to illustrate this process, which may find application in the tearing-mediated disruption of kinetic magnetorotational `channel' modes.
Bibtex entry for this abstract   Preferred format for this abstract (see Preferences)

Find Similar Abstracts:

Use: Authors
Keywords (in text query field)
Abstract Text
Return: Query Results Return    items starting with number
Query Form
Database: Astronomy
arXiv e-prints