CALCULATING LOW-ALTITUDE TRAPPED-PARTICLE FLUXES WITH THE NASA MODELSAP-8 AND AE-8

Accessing the NASA trapped radiation models AP-8 and AE-8 with (B,L) v alues obtained with modern geomagnetic held models causes an unrealist ic secular increase of the predicted flux over low altitude orbits. We show the secular variation of the orbit-averaged particle flux along the LDEF orbit and the mission dose, obtained using the AP-8 trapped r adiation models with an epoch-dependent magnetic field. The artificial ly increased epoch-dependent fluxes and doses are compared to the Aux and dose obtained with a consistent and more correct procedure for pre dicting fluxes with the NASA models. This procedure has been implement ed in the radiation analysis software package UNIRAD developed and dis tributed by BIRA-IASB. Copyright (C) 1996 Elsevier Science Ltd