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Multispectral Emission of the Sun during the First Whole Sun Month: Magnetohydrodynamic SimulationsWe demonstrate that a three-dimensional magnetohydrodynamic (MHD) simulation of the corona can model its global plasma density and temperature structure with sufficient accuracy to reproduce many of the multispectral properties of the corona observed in extreme ultraviolet (EW) and X-ray emission. The key ingredient to this new type of global MHD model is the inclusion of energy transport processes (coronal heating, anisotropic thermal conduction, and radiative losses) in the energy equation. The calculation of these processes has previously been confined to one-dimensional loop models, idealized two-dimensional computations, and three-dimensional active region models. We refer to this as the thermodynamic MHD model, and we apply it to the time period of Carrington rotation 1913 (1996 August 22 to September 18). The form of the coronal heating term strongly affects the plasma density and temperature of the solutions. We perform our calculation for three different empirical heating models: (1) a heating function exponentially decreasing in radius; (2) the model of Schrijver et al.; and (3) a model reproducing the heating properties of the quiet Sun and active regions. We produce synthetic emission images from the density and temperature calculated with these three heating functions and quantitatively compare them with observations from E W Imaging Telescope on the Solar and Heliospheric Observatory and the soft X-ray telescope on Yohkoh. Although none of the heating models provide a perfect match, heating models 2 and 3 provide a reasonable match to the observations.
Document ID
20090041864
Acquisition Source
Headquarters
Document Type
Reprint (Version printed in journal)
Authors
Lionello, Roberto
(Science Applications International Corp. San Diego, CA, United States)
Linker, Jon A.
(Science Applications International Corp. San Diego, CA, United States)
Mikic, Zoran
(Science Applications International Corp. San Diego, CA, United States)
Date Acquired
August 24, 2013
Publication Date
December 1, 2008
Publication Information
Publication: The Astrophysical Journal
Publisher: American Astronomical Society
Volume: 690
Subject Category
Solar Physics
Funding Number(s)
CONTRACT_GRANT: NNH08CC04C
Distribution Limits
Public
Copyright
Other

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