Orlova K. G., Y. Y. Shprits, (2010), Dependence of pitch-angle scattering rates and loss timescales on the magnetic field model, Geophysical Research Letters, 37, doi:10.1029/2009GL041639
Abstract
Radiation belt diffusion codes require, as inputs, precomputed scattering rates, which are currently bounce-averaged in the dipole magnetic field. We present the results of computations of the bounce-averaged quasi-linear pitch-angle diffusion coefficients of relativistic electrons for various distances and two MLT in the Tsyganenko 89c magnetic field model. The coefficients were computed for quiet and storm-time conditions. We compare scattering rates bounce-averaged in a non-dipole field model with those in the dipole field. We demonstrate that on the day side the effects of taking into account a realistic magnetic field are negligible at distances less than six Earth radii. On the night side diffusion coefficients may significantly depend on the assumed field model. Pitch-angle scattering rates calculated in the non-dipole field can explain the often observed night-side chorus induced precipitation. The physical explanation for the changes of pitch-angle scattering rates with the field model is presented and discussed.Authors (sorted by name)
Orlova ShpritsJournal / Conference
Geophysical Research LettersAcknowledgments
The research work was supported by Lab Research Fee grant 09‐LR‐04‐116720‐SHPY, NSF grant ATM 0603191, and NASA “Outer Plangrants Research” grant NNX07AL27G. The authors want to thank the developers of ONERA‐DESP library and Jerry Goldstein for useful discussions.Grants
09‐LR‐04116720 ATM‐0603191 NNX07AL27GBibtex
@article{doi:10.1029/2009GL041639,
author = {Orlova, Ksenia G. and Shprits, Yuri Y.},
title = {Dependence of pitch-angle scattering rates and loss timescales on the magnetic field model},
journal = {Geophysical Research Letters},
year = {2010},
volume = {37},
number = {5},
pages = {},
keywords = {pitch-angle diffusion, non-dipole field, chorus waves},
doi = {10.1029/2009GL041639},
url = {https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2009GL041639},
eprint = {https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2009GL041639},
abstract = {Radiation belt diffusion codes require, as inputs, precomputed scattering rates, which are currently bounce-averaged in the dipole magnetic field. We present the results of computations of the bounce-averaged quasi-linear pitch-angle diffusion coefficients of relativistic electrons for various distances and two MLT in the Tsyganenko 89c magnetic field model. The coefficients were computed for quiet and storm-time conditions. We compare scattering rates bounce-averaged in a non-dipole field model with those in the dipole field. We demonstrate that on the day side the effects of taking into account a realistic magnetic field are negligible at distances less than six Earth radii. On the night side diffusion coefficients may significantly depend on the assumed field model. Pitch-angle scattering rates calculated in the non-dipole field can explain the often observed night-side chorus induced precipitation. The physical explanation for the changes of pitch-angle scattering rates with the field model is presented and discussed.}
}