Dependence of pitch-angle scattering rates and loss timescales on the magnetic field model

作者：Orlova Ksenia G^*; Shprits Yuri Y

来源：Geophysical Research Letters, 2010, 37(5): L05105.

DOI：10.1029/2009GL041639

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. Citation: Orlova, K. G., and Y. Y. Shprits (2010), Dependence of pitch-angle scattering rates and loss timescales on the magnetic field model, Geophys. Res. Lett., 37, L05105, doi: 10.1029/2009GL041639.

• 出版日期2010-3-10