2016/03/09 by D. Del Sarto, Daniele Del Sarto, M. Ottaviani +1
Physics and Astronomy · #BETA (programming language) #Collisionality #Current sheet #Instability #Ionosphere and magnetosphere dynamics #Kink instability #Laser-Plasma Interactions and Diagnostics #Magnetic confinement fusion research #Magnetic reconnection #Magnetohydrodynamics #Plasma #Sawtooth wave #physics.plasm-ph
paper · pdf · doi:10.1063/1.4973328
7 pages, 3 figures
arxiv created 2016/03/09 · openalex created_date 2016/06/24 · openalex publication_date 2017/01/01 · arxiv updated 2017/09/13 · openalex updated_date 2026/08/05
In this work, we consider magnetic reconnection in thin current sheets with both resistive and electron inertia effects. When the current sheet is produced by a primary instability of the internal kink type, the analysis of secondary instabilities indicates that reconnection proceeds on a time scale much shorter than the primary instability characteristic time. In the case of a sawtooth crash, non-collisional physics becomes important above a value of the Lundquist number, which scales like S∼(R/de)12/5, in terms of the tokamak major radius R and of the electron skin depth de. This value is commonly achieved in present day devices. As collisionality is further reduced, the characteristic rate increases, approaching Alfvénic values when the primary instability approaches the collisionless regime.