Flux Rope Acceleration and Enhanced Magnetic Reconnection Rate

Technical Report · Tue Mar 25 04:00:00 EST 2003

DOI:https://doi.org/10.2172/813604· OSTI ID:813604

Cheng, C Z ^[1]; Ren, Y; Choe, G S; Moon, Y -J

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1. Princeton Plasma Physics Laboratory

A physical mechanism of flares, in particular for the flare rise phase, has emerged from our 2-1/2-dimensional resistive MHD simulations. The dynamical evolution of current-sheet formation and magnetic reconnection and flux-rope acceleration subject to continuous, slow increase of magnetic shear in the arcade are studied by employing a non-uniform anomalous resistivity in the reconnecting current sheet under gravity. The simulation results directly relate the flux rope's accelerated rising motion with an enhanced magnetic reconnection rate and thus an enhanced reconnection electric field in the current sheet during the flare rise phase. The simulation results provide good quantitative agreements with observations of the acceleration of flux rope, which manifests in the form of SXR ejecta or erupting filament or CMEs, in the low corona. Moreover, for the X-class flare events studied in this paper the peak reconnection electric field is about O(10{sup 2} V/m) or larger, enough to accelerate p articles to over 100 keV in a field-aligned distance of 10 km. Nonthermal electrons thus generated can produce hard X-rays, consistent with impulsive HXR emission observed during the flare rise phase.

• Research Organization: Princeton Plasma Physics Lab., NJ (US)
• Sponsoring Organization: USDOE Office of Science (SC) (US)
• DOE Contract Number: AC02-76CH03073
• OSTI ID: 813604
• Report Number(s): PPPL-3799
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
ACCELERATION
ELECTRIC FIELDS
ELECTRONS
MAGNETIC RECONNECTION
MAGNETOHYDRODYNAMICS (MHD)
SHEAR
SIMULATION
SOLAR FLARES
SPACE PLASMA PHYSICS