Relativistic solar cosmic rays in the December 7-8, 1982, event as a factor of magnetospheric disturbance in an analysis based on neutron-monitor data

Based on neutron-monitor data, we analyze the ground-level enhancement (GLE ) on December 7-8, 1982, which occurred under disturbed conditions with con siderable negative D-st, by using currently available magnetospheric models , Ostapenko-Mal'tsev-97 (OM-97) and Tsyganenko-89 (Ts89). We solve the inve rse problem by optimization methods and determine the parameters of the pri mary solar-cosmic-ray (SCR) radiation field outside the magnetosphere. The computed SCR parameters are compared with those obtained for quiet conditio ns in order to estimate the effect of allowance for disturbed magnetospheri c conditions. A comparative analysis of the various magnetospheric models i s performed.