@article{Johnson:2017:0004-6361/201629153,
author = {Johnson, CD and Hood, AW and de, Moortel I and Cargill, PJ},
doi = {0004-6361/201629153},
journal = {Astronomy & Astrophysics},
title = {A New Approach for Modelling Chromospheric Evaporation in Response to Enhanced Coronal Heating: 1 The Method},
url = {http://dx.doi.org/10.1051/0004-6361/201629153},
volume = {597},
year = {2017}
}

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TY  - JOUR
AB  - We present a new computational approach that addresses the difficulty of obtaining the correct interaction betweenthe solar corona and the transition region in response to rapid heating events. In the coupled corona/transition region/chromospheresystem, an enhanced downward conductive flux results in an upflow (chromospheric evaporation).However, obtaining the correct upflow generally requires high spatial resolution in order to resolve the transition region.With an unresolved transition region, artificially low coronal densities are obtained because the downward heatflux “jumps” across the unresolved region to the chromosphere, underestimating the upflows. Here, we treat the lowertransition region as a discontinuity that responds to changing coronal conditions through the imposition of a jumpcondition that is derived from an integrated form of energy conservation. To illustrate and benchmark this approachagainst a fully resolved one-dimensional model, we present field-aligned simulations of coronal loops in response to arange of impulsive (spatially uniform) heating events. We show that our approach leads to a significant improvement inthe coronal density evolution than just when using coarse spatial resolutions insufficient to resolve the lower transitionregion. Our approach compensates for the “jumping” of the heat flux by imposing a velocity correction that ensuresthat the energy from the heat flux goes into driving the transition region dynamics, rather than being lost throughradiation. Hence, it is possible to obtain improved coronal densities. The advantages of using this approach in bothone-dimensional hydrodynamic and three-dimensional magnetohydrodynamic simulations are discussed.
AU  - Johnson,CD
AU  - Hood,AW
AU  - de,Moortel I
AU  - Cargill,PJ
DO  - 0004-6361/201629153
PY  - 2017///
SN  - 0004-6361
TI  - A New Approach for Modelling Chromospheric Evaporation in Response to Enhanced Coronal Heating: 1 The Method
T2  - Astronomy & Astrophysics
UR  - http://dx.doi.org/10.1051/0004-6361/201629153
UR  - http://hdl.handle.net/10044/1/40126
VL  - 597
ER  - 

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