CAFE-PakalMPI: a new model to study the solar chromosphere in the NLTE approximation

TL;DR

This paper introduces CAFE-PakalMPI, a 3D NLTE MHD model coupling CAFE and PakalMPI to analyze solar chromospheric phenomena, including ionization and wave propagation, in a multi-processor environment.

Contribution

The paper presents a novel coupled 3D NLTE MHD model for the solar chromosphere, integrating ionization calculations with classical MHD simulations.

Findings

C7 model remains stable in the low chromosphere.

Wave propagation observed in the ionization rate of hydrogen.

Model effectively simulates chromospheric dynamics.

Abstract

We present a new numerical model called CAFE-PakalMPI with the capability to solve the equations of classical magnetohydrodynamic (MHD) and to obtain the multispecies whose ionization states are calculated through statistical equilibrium, using the approximation of non-local thermodynamic equilibrium (NLTE) in three dimensions with the multiprocessor environment. For this, we couple the Newtonian CAFE MHD code introduced in Gonz\'alez-Avil\'es et al. (2015) with PakalMPI presented in De la Luz et al. (2010). In this model, Newtonian CAFE solves the equations of ideal MHD under the effects of magnetic resistivity and heat transfer considering a fully ionized plasma. On the other hand, PakalMPI calculates the density of ionization states using the NLTE approximation for Hydrogen, electronic densities and H-, the other species are computed by the classical local thermodynamic equilibrium (LTE) approximation. The main purpose of the model focuses on the analysis of solar phenomena within the chromospheric region. As an application of the model, we study the stability of the C7 equilibrium atmospheric model with a constant magnetic field in a 3D environment. According to the results of the test, the C7 model remains stable in the low chromosphere, while in the range $z\in$[1.5,2.1] Mm we can observe the propagation of a wave produced by the changes in the ionization rate of H.