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Accession Number N20120010348
Title Formation and Evolution of a Multi-Threaded Prominence.
Publication Date 2012
Media Count 29p
Personal Author C. R. DeVore J. T. Karpen M. Luna
Abstract We investigate the process of formation and subsequent evolution of prominence plasma in a filament channel and its overlying arcade. We construct a three-dimensional time-dependent model of a filament-channel prominence suitable to be compared with observations. We combine this magnetic field structure with one-dimensional independent simulations of many flux tubes. The magnetic structure is a three-dimensional sheared double arcade, and the thermal non-equilibrium process governs the plasma evolution. We have found that the condensations in the corona can be divided into two populations: threads and blobs. Threads are massive condensations that linger in the field line dips. Blobs are ubiquitous small condensations that are produced throughout the filament and overlying arcade magnetic structure, and rapidly fall to the chromosphere. The total prominence mass is in agreement with observations. The threads are the principal contributors to the total mass, whereas the blob contribution is small. The motion of the threads is basically horizontal, while blobs move in all directions along the field. The peak velocities for both populations are comparable, but there is a weak tendency for the velocity to increase with the inclination, and the blobs with motion near vertical have the largest values of the velocity. We have generated synthetic images of the whole structure in an H proxy and in two EUV channels of the AIA instrument aboard SDO. These images show the plasma at cool, warm and hot temperatures. The theoretical differential emission measure of our system agrees very well with observations in the temperature range log T = 4.6-5.7. We conclude that the sheared-arcade magnetic structure and plasma dynamics fit well the abundant observational evidence.
Keywords Coronas
Magnetic field configurations
Magnetic flux
Plasmas(Physics)
Simulation
Thermodynamic equilibrium
Threads
Three dimensional models
Time dependence

 
Source Agency National Aeronautics and Space Administration
NTIS Subject Category 54C - Astrophysics
46G - Plasma Physics
Corporate Author Goddard Space Flight Center, Greenbelt, MD.
Document Type Journal article
Title Note N/A
NTIS Issue Number 1226
Contract Number N/A

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