@Article{SilvaSantBuchAlve:2018:NoHeFl,
author = "Silva, Suzana de Souza e Almeida and Santos, J. C. and Buchner, J.
and Alves, Maria Virginia",
affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and
{Universidade Tecnol{\'o}gica Federal do Parana (UTFPR)} and {Max
Planck Institut f{\"u}r Sonnensystemforschung (MPS)} and
{Instituto Nacional de Pesquisas Espaciais (INPE)}",
title = "Nonlocal heat flux effects on temperature evolution of the solar
atmosphere",
journal = "Astronomy \& Astrophysics",
year = "2018",
volume = "615",
pages = "A32",
month = "July",
keywords = "Sun: corona, Sun: atmosphere, magnetohydrodynamics (MHD).",
abstract = "Context. Heat flux is one of the main energy transport mechanisms
in the weakly collisional plasma of the solar corona. There, rare
binary collisions let hot electrons travel over long distances and
influence other regions along magnetic field lines. Thus, the
fully collisional heat flux models might not describe transport
well enough since they consider only the local contribution of
electrons. The heat flux in weakly collisional plasmas at high
temperatures with large mean free paths has to consider the
nonlocality of the energy transport in the frame of nonlocal
models in order to treat energy balance in the solar atmosphere
properly. Aims. We investigate the impact of nonlocal heat flux on
the thermal evolution and dynamics of the solar atmosphere by
implementing a nonlocal heat flux model in a 3D
magnetohydrodynamic simulation of the solar corona. Methods. We
simulate the evolution of solar coronal plasma and magnetic fields
considering both a local collision dominated and a nonlocal heat
flux model. The initial magnetic field is obtained by a potential
extrapolation of the observed line-of-sight magnetic field of
AR11226. The system is perturbed by moving the plasma at the
photosphere. We compared the simulated evolution of the solar
atmosphere in its dependence on the heat flux model. Results. The
main differences for the average temperature profiles were found
in the upper chromosphere/transition region. In the nonlocal heat
transport model case, thermal energy is transported more
efficiently to the upper chromosphere and lower transition region
and leads to an earlier heating of the lower atmosphere. As a
consequence, the structure of the solar atmosphere is affected
with the nonlocal simulations producing on average a smoother
temperature profile and the transition region placed about 500 km
higher. Using a nonlocal heat flux also leads to two times higher
temperatures in some of the regions in the lower corona.
Conclusions. The results of our 3D MHD simulations considering
nonlocal heat transport supports the previous results of simpler
1D two-fluid simulations. They demonstrated that it is important
to consider a nonlocal formulation for the heat flux when there is
a strong energy deposit, like the one observed during flares, in
the solar corona.",
doi = "10.1051/0004-6361/201730580",
url = "http://dx.doi.org/10.1051/0004-6361/201730580",
issn = "0004-6361 and 1432-0746",
language = "en",
targetfile = "silva_nonlocal.pdf",
urlaccessdate = "29 mar. 2024"
}