PyEPPAurora¶

Atmospheric ionization from particle precipitation

Bundles some of the parametrizations for middle and upper atmospheric ionization and recombination rates for precipitating auroral and radiation-belt electrons as well as protons. Includes also some recombination rate parametrizations to convert the ionization rates to electron densities in the upper atmosphere. See References for a list of included parametrizations.

:warning: This package is in beta stage, that is, it works for the most part and the interface should not change (much) in future versions.

Documentation is available at https://pyeppaurora.readthedocs.io.

Install¶

Requirements¶

numpy - required
scipy - required for 2-D interpolation
pytest - optional, for testing

eppaurora¶

An installable pip package called eppaurora is available from the main package repository, it can be installed with:

$ pip install eppaurora

The latest development version can be installed with pip directly from github (see https://pip.pypa.io/en/stable/reference/pip_install/#vcs-support and https://pip.pypa.io/en/stable/reference/pip_install/#git):

$ pip install [-e] git+https://github.com/st-bender/pyeppaurora.git

The other option is to use a local clone:

$ git clone https://github.com/st-bender/pyeppaurora.git
$ cd pyeppaurora

and then using pip (optionally using -e, see https://pip.pypa.io/en/stable/reference/pip_install/#install-editable):

$ pip install [-e] .

or using setup.py:

$ python setup.py install

Optionally, test the correct function of the module with

$ py.test [-v]

or even including the doctests in this document:

$ py.test [-v] --doctest-glob='*.md'

Usage¶

The python module itself is named eppaurora and is imported as usual.

All functions should be numpy-compatible and work with scalars and appropriately shaped arrays.

>>> import eppaurora as aur
>>> ediss = aur.rr1987(1., 1., 8e5, 5e-10)
>>> ediss
3.3693621076457477e-10
>>> import numpy as np
>>> energies = np.logspace(-1, 2, 4)
>>> fluxes = np.ones_like(energies)
>>> # ca. 100, 150, 200 km
>>> scale_heights = np.array([6e5, 27e5, 40e5])
>>> rhos = np.array([5e-10, 1.7e-12, 2.6e-13])
>>> # energy dissipation "profiles"
>>> # broadcast to the right shape
>>> ediss_prof = aur.fang2008(
... 	energies[None, :], fluxes[None, :],
... 	scale_heights[:, None], rhos[:, None]
... )
>>> ediss_prof
array([[1.37708081e-49, 3.04153876e-09, 4.44256875e-07, 2.52699970e-08],
       [1.60060833e-09, 8.63248169e-08, 3.64564419e-09, 1.62591310e-10],
       [5.19369952e-08, 2.34089350e-08, 5.17379303e-10, 3.19504690e-11]])

Basic class and method documentation is accessible via pydoc:

$ pydoc eppaurora
$ pydoc eppaurora.brems
$ pydoc eppaurora.conductivity
$ pydoc eppaurora.electrons
$ pydoc eppaurora.protons
$ pydoc eppaurora.recombination

References¶

Electron ionization¶

[1]: Roble and Ridley, Ann. Geophys., 5A(6), 369–382, 1987
[2]: Fang et al., J. Geophys. Res. Space Phys., 113, A09311, 2008, doi: 10.1029/2008JA013384
[3]: Fang et al., Geophys. Res. Lett., 37, L22106, 2010, doi: 10.1029/2010GL045406

Ionization by secondary electrons from bremsstrahlung¶

[4]: Berger et al., Journal of Atmospheric and Terrestrial Physics, Volume 36, Issue 4, 591–617, April 1974, doi: 10.1016/0021-9169(74)90085-3

Proton ionization¶

[5]: Fang et al., J. Geophys. Res. Space Phys., 118, 5369–5378, 2013, doi: 10.1002/jgra.50484

Recombination rates¶

[6]: Vickrey et al., J. Geophys. Res. Space Phys., 87, A7, 5184–5196, doi: 10.1029/ja087ia07p05184
[7]: Gledhill, Radio Sci., 21, 3, 399-408, doi: 10.1029/rs021i003p00399
[8]: https://ssusi.jhuapl.edu/data_algorithms

Conductivity and conductance¶

[9]: Brekke et al., J. Geophys. Res., 79(25), 3773–3790, Sept. 1974, doi: 10.1029/JA079i025p03773
[10]: Vickrey et al., J. Geophys. Res., 86(A1), 65–75, Jan. 1981, doi: 10.1029/JA086iA01p00065
[11]: Robinson et al., J. Geophys. Res. Space Phys., 92(A3), 2565–2569, Mar. 1987, doi: 10.1029/JA092iA03p02565

License¶

This python interface is free software: you can redistribute it or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2 (GPLv2), see local copy or online version.