Direct implicit simulation of collisionless magnetic reconnection

Conference · Wed Jul 12 04:00:00 EDT 1989

OSTI ID:7161998

Francis, G. E.; Hewett, D. W.; Max, C. E.

Collisionless reconnection of magnetic field lines depends upon electron inertia effects and details of the electron and ion distribution functions, thus requiring a kinetic description of both. Though traditional explicit PIC techniques provide this description in principle, they are severely limited in parameters by time step constraints. This parameter regime has been expanded in this work by using the recently constructed 2.5 D electromagnetic code AVANTI. The code runs stably with arbitrarily large {Delta}t and is quite robust with respect to large fluctuations occurring due to small numbers of particles per cell. We find excellent agreement with linear electron tearing theory for early simulation times, provided electrostatic effects are included in the theory. In the non-linear regime following tearing, we observe electrostatic ringing of electrons and trapped flux into the magnetic island, superposed on linear growth determined by the ion sound velocity. It is found that the inclusion of a guide magnetic field (magnetic shear) severely slows the initial stages of reconnection and damps out the electrostatic ringing if local values of the guide field are above a threshold determined by questions of electron mobility. 21 refs., 8 figs.

• Research Organization: Lawrence Livermore National Lab., CA (USA)
• Sponsoring Organization: DOE/DP
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 7161998
• Report Number(s): UCRL-101516; CONF-8903131--4; ON: DE90007250
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700202* -- Fusion Power Plant Technology-- Magnet Coils & Fields
COLLISIONLESS PLASMA
EARTH ATMOSPHERE
EARTH MAGNETOSPHERE
ELECTRIC FIELDS
MAGNETIC FIELD CONFIGURATIONS
MAGNETIC FLUX
MAGNETIC ISLANDS
PLASMA
PLASMA SHEET
PLASMA SIMULATION
SHEAR
SIMULATION