National Aeronautics and Space Administration

Living With A Star

Targeted Research and Technology

Physics-based Modeling of Emission in Active Regions

ROSES ID: NNH06ZDA001N      Selection Year: 2007      

Program Element: Focused Science Topic

Principal Investigator: Roberto Lionello

Affiliation(s): Science Applications International Corporation

Project Member(s):
Linker, Jon A Co-I Predictive Science, Inc.
Klimchuk, James A Co-I NASA Goddard Space Flight Center


The structure and dynamics of active region magnetic fields play a crucial

role in the production of EUV and X-ray emission from the Sun. A key

impediment to a more comprehensive understanding and prediction of this

emission has been that models of active region magnetic fields based on real

data (e.g., nonlinear force-free models) have largely been disconnected from

studies of coronal heating and emission.

Static loop models, the most common method for study emission, have thus far

been unsuccessful in explaining some important properties of coronal loops.

We propose to use physics-based models of active region magnetic fields that

use solar magnetograms as boundary conditions and include realistic energy

transport (radiative losses, anisotropic thermal conduction, and coronal

heating) in the transition region and corona to investigate emission in

active regions.

We will investigate three aspects of active region physics

that may lead to time-dependent behavior of the coronal plasma:

(1) Thermal non-equilibrium; (2) Non-steady coronal heating; (3) Magnetic

field evolution. Preliminary results suggest our model may be capable

of explaining some of the mysterious properties of coronal loops.

Our model will produce quantitative predictions

of emission that we will test against observations from SOHO, TRACE,

Yohkoh, and SXI. Our proposed program is also highly relevant to the

upcoming Solar-B, STEREO, and SDO missions.


Performance YearReferenceInvestigation TypeActions
1Lionello, R., Linker, J. A., and Mikic, Z. 2009, "Multispec...
not set
1Riley, Pete; Linker, Jon A.; Mikic, Zoran; Lionello,...
not set
1Lionello, Roberto; Linker, Jon A.; Mikić, Zoran; (200...
not set


Performance YearReferenceActions
1Linker, Jon A.; Lionello, R.; Mikic, Z.; Riley, P.;...
1Mok, Yung; Mikic, Z.; Lionello, R.; Linker, J.; (2007...
1Mok, Y.; Lionello, R.; Mikic, Z.; Linker, J. A.; (20...
1Lionello, R.; Linker, J. A.; Mikić, Z.; Mok, Y.; (2...
1Mok, Yung; Lionello, R.; Mikic, Z.; Linker, J.; (2009...

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