The 3D and Dynamic Solar Atmosphere
Regner Trampedach [trampeda@lcd.colorado.edu], Joint Institute for Laboratory
Astrophysics (JILA), University of Colorado, Boulder
The light we observe from the Sun has escaped from its convective photosphere. A
model describing the Sun's emergent spectrum therefore needs to include convection, and
mere mixing length models are often inadequate. I present my work on 3D simulations
of the solar surface layers (from 3 Mm below to 1 Mm above the photosphere), with
emphasis on the best available atomic physics and a (LTE) radiative transfer scheme that
is as realistic as possible within the constraints of computational power. These
simulations have been tested extensively against a wide range of observations such as
continuum limb darkening, strong hydrogen lines, flux spectrum and limb darkening in
lines. This work was also the basis for the solar abundance analysis carried out by
Asplund, Grevesse, Sauval and Scott (2009). I will also present some experiments I have
performed on the simulations to assess the sensitivity of the emergent spectra to various
changes in the atmospheric temperature structure.