With current observational methods it is not possible to directly measure the
magnetic field in the solar corona with sufficient accuracy. Therefore, coronal
magnetic field models have to rely on extrapolation methods using photospheric
magnetograms as boundary conditions. In recent years, due to the increased
resolution of observations and the need to resolve non-force-free lower regions
of the solar atmosphere, there have been increased efforts to use
magnetohydrostatic (MHS) field models instead of force-free extrapolation
methods. Although numerical methods to calculateMHS solutions can deal with
non-linear problems and hence provide more accurate models, analytical
three-dimensional MHS equilibria can also be used as a numerically relatively
“cheap” complementary method. In this paper, we present an extrapolation method
based on a family of analytical MHS equilibria that allows for a transition
from a non-force-free region to a force-free region. We demonstrate how
asymptotic forms of the solutions can help to increase the numerical efficiency
of the method. Through both artificial boundary condition testing and a first
application to observational

Este artículo explora los viajes en el tiempo y sus implicaciones.

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