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Title: A Titov–Démoulin Type Eruptive Event Generator for β > 0 Plasmas
Abstract

We provide exact analytical solutions for the magnetic field produced by prescribed current distributions located inside a toroidal filament of finite thickness. The solutions are expressed in terms of toroidal functions, which are modifications of the Legendre functions. In application to the MHD equilibrium of a twisted toroidal current loop in the solar corona, the Grad–Shafranov equation is decomposed into an analytic solution describing an equilibrium configuration against the pinch-effect from its own current and an approximate solution for an external strapping field to balance the hoop force. Our solutions can be employed in numerical simulations of coronal mass ejections (CMEs). When superimposed on the background solar coronal magnetic field, the excess magnetic energy of the twisted current loop configuration can be made unstable by applying flux cancellation to reduce the strapping field. Such loss of stability accompanied by the formation of an expanding flux rope is typical for the Titov & Démoulin eruptive event generator. The main new features of the proposed model are as follows: the filament is filled with finiteβplasma with finite mass and energy, the model describes an equilibrium solution that will spontaneously erupt due to magnetic reconnection of the strapping magnetic field arcade, and there are analytic expressions connecting the model parameters to the asymptotic velocity and total mass of the resulting CME, providing a way to connect the simulated CME properties to multipoint coronograph observations.

 
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Award ID(s):
2149771
NSF-PAR ID:
10493811
Author(s) / Creator(s):
;
Publisher / Repository:
ApJ
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
955
Issue:
2
ISSN:
0004-637X
Page Range / eLocation ID:
126
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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