Bibcode
Martínez-Sykora, J.; De Pontieu, Bart; Carlsson, Mats; Hansteen, Viggo H.; Nóbrega-Siverio, D.; Gudiksen, Boris V.
Bibliographical reference
The Astrophysical Journal, Volume 847, Issue 1, article id. 36, 17 pp. (2017).
Advertised on:
9
2017
Journal
Citations
62
Refereed citations
58
Description
We investigate the effects of interactions between ions and neutrals on
the chromosphere and overlying corona using 2.5D radiative MHD
simulations with the Bifrost code. We have extended the code
capabilities implementing ion–neutral interaction effects using
the generalized Ohm’s law, i.e., we include the Hall term and the
ambipolar diffusion (Pedersen dissipation) in the induction equation.
Our models span from the upper convection zone to the corona, with the
photosphere, chromosphere, and transition region partially ionized. Our
simulations reveal that the interactions between ionized particles and
neutral particles have important consequences for the
magnetothermodynamics of these modeled layers: (1) ambipolar diffusion
increases the temperature in the chromosphere; (2) sporadically the
horizontal magnetic field in the photosphere is diffused into the
chromosphere, due to the large ambipolar diffusion; (3) ambipolar
diffusion concentrates electrical currents, leading to more violent jets
and reconnection processes, resulting in (3a) the formation of longer
and faster spicules, (3b) heating of plasma during the spicule
evolution, and (3c) decoupling of the plasma and magnetic field in
spicules. Our results indicate that ambipolar diffusion is a critical
ingredient for understanding the magnetothermodynamic properties in the
chromosphere and transition region. The numerical simulations have been
made publicly available, similar to previous Bifrost simulations. This
will allow the community to study realistic numerical simulations with a
wider range of magnetic field configurations and physics modules than
previously possible.
Related projects
Numerical Simulation of Astrophysical Processes
Numerical simulation through complex computer codes has been a fundamental tool in physics and technology research for decades. The rapid growth of computing capabilities, coupled with significant advances in numerical mathematics, has made this branch of research accessible to medium-sized research centers, bridging the gap between theoretical and
Daniel Elías
Nóbrega Siverio