6533b872fe1ef96bd12d3aaf
RESEARCH PRODUCT
MHD modeling of coronal loops: the transition region throat
James A. KlimchukSalvatore OrlandoFabio RealeFabio RealeAndrea MignoneMassimiliano Guarrasisubject
PhysicsMagnetohydrodynamics (MHD)Sun: coronaMagnetohydrodynamics (MHD); Sun: corona; Sun: magnetic fields; Sun: transition region; Astronomy and Astrophysics; Space and Planetary ScienceFOS: Physical sciencesAstronomy and AstrophysicsPlasmaAstrophysicsMechanicsCoronal loopRadiationThermal conductionMagnetic fieldLoop (topology)corona Sun: magnetic fields Sun: transition region magnetohydrodynamics (MHD) [Sun]Settore FIS/05 - Astronomia E AstrofisicaAstrophysics - Solar and Stellar AstrophysicsSpace and Planetary ScienceSun: corona Sun: magnetic fields Sun: transition region magnetohydrodynamics (MHD)MagnetohydrodynamicsCurrent (fluid)Sun: transition regionSun: magnetic fieldsSolar and Stellar Astrophysics (astro-ph.SR)description
The expansion of coronal loops in the transition region may considerably influence the diagnostics of the plasma emission measure. The cross sectional area of the loops is expected to depend on the temperature and pressure, and might be sensitive to the heating rate. The approach here is to study the area response to slow changes in the coronal heating rate, and check the current interpretation in terms of steady heating models. We study the area response with a time-dependent 2D MHD loop model, including the description of the expanding magnetic field, coronal heating and losses by thermal conduction and radiation from optically thin plasma. We run a simulation for a loop 50 Mm long and quasi-statically heated to about 4 MK. We find that the area can change substantially with the quasi-steady heating rate, e.g. by ~40% at 0.5 MK as the loop temperature varies between 1 and 4 MK, and, therefore, affects the interpretation of DEM(T) curves.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2014-01-01 |