Changes of the neutral and ionized composition in the D-region after solar proton event in October 1989 (model simulations)

One of the strongest solar proton events (SPE) occurred in October 1989. The ionized layer in the atmosphere is a result of interaction between radiation (electromagnetic and particle) and the neutral atmosphere. Changes of the neutral and ionized composition due to this event are examined. The ionization rate, and ozone, NO and OH density temporal and spatial (vertical) deviations induced by the SPE, calculated by a I-D time dependent photochemical model separately for daytime and nighttime are used in a I-D model of the lower ionosphere to calculate the response of ionized components and other parameters of the lower ionosphere. The results of model calculations are compared with the empirical model of high-latitude electron densities, with rocket measurements of O-3 and n(+) from Russian research vessel, with parameter f(+) obtained for November 1969 SPE and with experimental a(eff) data for disturbed conditions. (C) 2003 COSPAR. Published by Elsevier Ltd. All rights reserved.