RELATION BETWEEN MAGNETIC SHELL PARAMETER L, Dst AND IMF

It is a new trend to use the magnetic coordinate L-Λ. to describe space particle features and position of spacecraft. T96 model is used to calculate magnetic shell parameter, and the difference between L values calculated from Dipolar model, IGRF and T96 were compared. The difference between L values calculated from Dipolar model and IGRF, begin to increase when magnetic latitude is larger than 30? Also,the difference between L values calculated from IGRF and T96, begin to increase when magnetic latitude is larger than 50? The L values are therefore dependent on the IMF （interplanetary magnetic field） and have also the dependence of local time. This work is meaningful to radiation belt dynamic modeling and understanding of magnetic position of satellite.