Dissertation/Thesis Abstract

Modeling eruptive coronal magnetohydrodynamic systems with FLUX
by Rachmeler, L. A., Ph.D., University of Colorado at Boulder, 2010, 138; 3404053
Abstract (Summary)

In this dissertation I explore solar coronal energetic eruptions in the context of magnetic reconnection, which is commonly thought to be a required trigger mechanism for solar eruptions. Reconnection is difficult to directly observe in the corona, and current numerical methods cannot model reconnectionless control cases. Thus, it is not possible to determine if reconnection is a necessary component of these eruptions. I have executed multiple controlled simulations to determine the importance of reconnection for initiation and evolution of several eruptive systems using FLUX, a numerical model that uses the comparatively new fluxon technique.

I describe two types of eruptions modeled with FLUX: a metastable confined flux rope theory for coronal mass ejection (CME) initiation, and symmetrically twisted coronal jets in a uniform vertical background field. In the former, I identified an ideal magnetohydrodynamic (MHD) instability that allows metastable twisted flux rope systems to suddenly lose stability and erupt even in the absence of reconnection, contradicting previous conjecture. The CME result is in contrast to the azimuthally symmetric coronal jet initiation model, where jet-like behavior does not manifest without reconnection.

My work has demonstrated that some of the observed eruptive phenomena may be triggered by non-reconnective means such as ideal MHD instabilities, and that magnetic reconnection is not a required element in all coronal eruptions.

Indexing (document details)
Advisor: DeForest, Craig E.
Commitee: Ayres, Tom, Bagenal, Fran, Flaxman, Samuel M., Gibson, Sarah E., Rast, Mark P.
School: University of Colorado at Boulder
Department: Astrophysical and Planetary Sciences
School Location: United States -- Colorado
Source: DAI-B 71/06, Dissertation Abstracts International
Source Type: DISSERTATION
Subjects: Astrophysics, Electromagnetics, Plasma physics
Keywords: Coronal mass ejections, Magnetohydrodynamic systems, Solar eruptions
Publication Number: 3404053
ISBN: 9781109782318
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