LIR-ACheM documentation

This project is the implementation of an ion scheme to model the D-region ions’ and electron’s dynamics during solar flares, and the computation of the resulting HF absorption.

Note

This project is under active development. The description of each function and their requirements is available in Functions. An additional example of how to use this library and some results are available in the repository through theExample_useJupyter notebook.

Note

Throughout the code and the documentation, all quantities are in units ofcmands. The only exceptions are the altitudes and scale-height, which are given inkm.

Contents

Introduction

• Installation
  • Requirements
• Quickstart
  • Output
• Main objects
  • Neutrals
  • Electrons
  • Radiation
  • Ions

Chemistry in the D-region

• Ion chemistry in the D-region
  • Description of the model
  • Assumptions
  • Chemistry coefficients
• Neutral background
  • Neutral densities
    • \(NO\)
    • \(H_2O\)
    • \(O_3\)
  • Results
• Absorption of the solar flux
  • Theory
  • Practice
  • Results
  • HXR
• Photoionisation of neutral species
  • Ionisation by cosmic rays
  • Ionisation by solar flux
    • Ionisation of \(O^+\) and \(N^+\)
    • Ionisation of \(O_2(^1 \Delta_g)\)
• Initialisation of ions
  • First initialisation of ions
  • Second initialisation of ions

HF absorption

• Collision frequencies
• Computing the HF absorption
  • Refractive index
    • Use of the Appleton-Hartree equation
    • The plasma frequency
    • The electron cyclotron frequency
  • Computation of the absorption
  • Practice
  • Results

Additional ressources

• Bibliography
• Functions

Note:

LIR-ACheM stands for Lower Ionosphere Region - Absorption & Chemistry Modelling. It has been written by P. Teysseyre and C. Briand (LIRA, Observatoire de Paris, Université PSL, Sorbonne Université, Université Paris Cité, CY Cergy Paris Université, CNRS, Meudon, France)