Model CRAC:EPII for atmospheric ionization due to precipitating electrons: Yield function and applications

作者：Artamonov A A; Mishev A L; Usoskin I G

来源：JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS, 2016, 121(2): 1736-1743.

DOI：10.1002/2015JA022276

• atmospheric ionization
• Monte Carlo
• precipitating electrons

A new model of the family of CRAC models, CRAC:EPII (Cosmic Ray Atmospheric Cascade: Electron Precipitation Induced Ionization), is presented. The model calculates atmospheric ionization induced by precipitating electrons and uses the formalism of ionization yield functions. The CRAC:EPII model is based on a full Monte Carlo simulation of electron propagation and interaction with the air molecules. It explicitly considers various physical processes, namely, pair production, Compton scattering, generation of bremsstrahlung high-energy photons, photoionization, annihilation of positrons, and multiple scattering. The simulations were performed using GEANT 4 simulation tool PLANETOCOSMICS with NRLMSISE 00 atmospheric model. The CRAC:EPII model is applicable to the entire atmosphere. The results from the simulations are given as look-up table representing the ionization yield function. The table allows one to compute ionization due to precipitating electrons for a given altitude and location considering a given electron spectrum. Application of the model for computation of ion production during electron precipitation events using spectra from balloon-borne measurements is presented.

• 出版日期2016-2