nonWKB_AlfvenWave solver

Solve the two Elsasser variables given background solar wind profiles. 1D spherical coordinate system is used. Please refer to nonWKB_Alfven_wave_solver.pdf for the equation set that is solved by this solver.

parameters.py: Input parameters.

background_fields.py: Functions that calculate background fields, including solar wind speed $U(r)$, Alfven speed $V_A(r)$, and density $\rho(r)$, and their 1st-order and 2nd-order derivatives. Note that density is not directly used in integrating the equation but is used in calculating $V_A(r)$ and $U(r)$. The 2nd-order derivatives are used only at the Aflven point. By default, the models are taken from Waves from the Sun? by Velli et al. (1991). The users can define their own background fields either analytically or from interpolated satellite data (hint: scipy.interpolate package can return a callable function from interpolated data). Note: It is assumed that $U(r)$ and $V_A(r)$ only have one crossing, i.e. there is only one Alfven point.

functions_for_integral.py: Core functions that are used in integrating the equation set. The users do not need to modify this file.

main.py: Main file to be run. By default, a set of output files will be generated in .npy format.

plot_data.py: Generate plots from the .npy data.

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Copyright (C) 2024 Chen Shi (cshi1993@ucla.edu)

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.