Thermal conduction in a mirror-unstable plasmaReport as inadecuate

Thermal conduction in a mirror-unstable plasma - Download this document for free, or read online. Document in PDF available to download.

Reference: Komarov, SV, Churazov, EM, Kunz, MW et al., (2016). Thermal conduction in a mirror-unstable plasma. Monthly Notices of the Royal Astronomical Society, 460 (1), 467-477.Citable link to this page:


Thermal conduction in a mirror-unstable plasma

Abstract: The plasma of galaxy clusters is subject to firehose and mirror instabilities at scales of order the ion Larmor radius. The mirror instability generates fluctuations of magnetic-field strength δB/B∼1. These fluctuations act as magnetic traps for the heat-conducting electrons, suppressing their transport. We calculate the effective parallel thermal conductivity in the ICM in the presence of the mirror fluctuations for different stages of the evolution of the instability. The mirror fluctuations are limited in amplitude by the maximum and minimum values of the field strength, with no large deviations from the mean value. This key property leads to a finite suppression of thermal conduction at large scales. We find suppression down to ≈0.2 of the Spitzer value for the secular phase of the perturbations’ growth, and ≈0.3 for their saturated phase. The effect operates in addition to other suppression mechanisms and independently of them. Globally, fluctuations δB/B∼1 can be present on much larger scales, of the order of the scale of turbulent motions. However, we do not expect large suppression of thermal conduction by these, because their scale is considerably larger than the collisional mean free path of the ICM electrons. The obtained suppression of thermal conduction by a factor of ∼5 appears to be characteristic and potentially universal for a weakly collisional mirror-unstable plasma.

Publication status:PublishedPeer Review status:Peer reviewedVersion:Publisher's versionDate of acceptance:2016-04-19 Funder: Russian Scientific Foundation   Notes:© 2016 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society

Bibliographic Details

Publisher: Oxford University Press

Publisher Website:

Journal: Monthly Notices of the Royal Astronomical Societysee more from them

Publication Website:

Volume: 460

Issue: 1

Extent: 467-477

Issue Date: 2016-04



Issn: 1365-2966

Issn: 0035-8711

Uuid: uuid:c3bc37d5-2856-42fc-8771-f27c071f3bff

Urn: uri:c3bc37d5-2856-42fc-8771-f27c071f3bff

Pubs-id: pubs:637678 Item Description

Type: journal-article;

Version: Publisher's versionKeywords: conduction instabilities magnetic fields plasmas galaxies: clusters: intra-cluster medium *keyword*


Author: Komarov, SV - - - Churazov, EM - - - Kunz, MW - - - Schekochihin, A - Oxford, MPLS, Physics, Theoretical Physics - - - - Bibliogr



Related documents