This model describes the ionospheric ion composition as a function of altitude, solar zenith angle, latitude, solar radio flux, and month. It is based on an earlier model by Danilov and Semenov (1978) on satellite data from Electron 2, 4 and S3-1, and on data from 20 high apogee rocket flights. Fifty-four reference profiles were constructed for O+, 18 for NO+, O+2, H+, He+, and N+, and six for Cluster ions. Simple analytical functions are used to represent the variation with altitude, solar zenith angle, latitude (only O+, N+, He+, H+), season (only NO+, O+2, O+, Cluster), and solar activity (all except Cluster).
Availability: On tape, diskette, networks as part of the International Reference Ionosphere
A. D. Danilov and V. K. Semenov, Atmospheric Ion Composition Measurements Up to a Height of 170 km, Space Research XIII, 493, Akademie-Verlag, Berlin, 1973.
A. D. Danilov and V. K. Semenov, Relative Ion Composition Model at Mid-Latitudes, J. Atmos. Terr. Phys. 40, 1093, 1978.
A. D. Danilov and A. P. Yaichnikov, A New Model of the Ion Composition at 75 to 1000 km for IRI, Adv. Space Res. 5, 75, 1985.