  Magnetic field line curvature scattering(FLCS) happens when particle gyro-radius is comparable to magnetic field line curvature radius, and the conservation of the first adiabatic invariant is broken. As a collision-less particle scattering mechanism, FLCS plays a vital role in affecting the distribution of energetic electrons in the radiation belt, precipitation of ring current ions, and the formation of proton isotropic boundary(IB). In recent years, it has been increasingly used in research on particle dynamics. Previous studies focused on quantifying the effects of curvature scattering in a single case. This paper uses the analytic model to calculate the spatial distribution of diffusion coefficients induced by FLCS in a real magnetic field model. Various energy particles are used to analyze the coverage of curvature scattering in radial and MLT directions, as well as the influence of $Kp$ index. The decay time of particles due to curvature scattering is estimated based on diffusion coefficients which suggest that the time scale of curvature scattering is too long to explain the rapid loss of electrons in the radiation belt and the ring current with the energy of MeV or below MeV. However, the decay time of ring current protons is on the order of hours or even minutes which can be used to explain the ring current decay during the recovery phase of magnetic storm. Finally, the effects of resonant wave-particle scattering and FLCS in the vicinity of the midnight equator are briefly compared. It is found that the influence of FLCS on hundred-keV protons in the ring current region is comparable to or even greater than that of EMIC wave scattering. Our results suggest the non-negligible effects of the FLCS and should be considered in radiation belt and ring current modeling. 
Quantifying the Effects of Magnetic Field Line Curvature Scattering on   Radiation Belt and Ring Current Particles