Solar Physics Division Meeting 2000, June 19-22
Session 1. Helioseismology, Magnetic Fields, Chromosphere and Transition Region
Display, Chair: C. U. Keller, Monday-Thursday, June 19, 2000, 8:00am-6:00pm, Forum Ballroom

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[1.36] The Cohesion of 3-D Magnetic Flux Tubes in a Rotating, Stratified Model Convection Zone

W. Abbett, G. Fisher (University of California, Berkeley), Y. Fan (HAO, National Center for Atmospheric Research)

We present the latest results from a series of 3-D MHD simulations in the anelastic approximation that describe the rise of magnetic flux tubes through an adiabatically stratified model convection zone. The effects of solar rotation and the Coriolis force are included in the models. The simulations begin with initially horizontal magnetic flux tubes which subsequently evolve into Omega-loops. We find that the degree of ``fragmentation'' at the apex of a rising Omega-loop depends strongly on both the three-dimensional geometry of the loop, and on the field strength along the axis of the initial tube. Loops with a relatively high degree of apex curvature, and of moderate to low initial axial field strength retain their cohesion throughout their rise toward the photosphere --- even in the absence of initial field line twist. We are able to infer general observational characteristics of the emerging flux, and compare our theoretical data with recent observations of active regions.

This work was funded by NSF grants AST 98-19727 and ATM 98-96316, and by NASA grant NAGS-8468. The computations were partially supported by the National Center for Atmospheric Research, and the National Computational Science Alliance.


The author(s) of this abstract have provided an email address for comments about the abstract: abbett@ssl.berkeley.edu

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