Theoretical Calculations for Ionospheric Modelling at Delhi for Medium Solar Activity Conditions

Abstract

Theoretical calculations are done for the ion composition and electron and ion temperatures at Delhi by solving the continuity, momentum and energy equations for medium solar activity conditions (<i>F</i> _10-7= 140 units). The variations in different input parameters are considered and their effects are studied on the ion composition and temperature profiles, Based on these studies and their comparisons with the available observed results, the best values of the input parameters are chosen. In the final input parameters, the Hinteregger solar BUV fluxes [Hinteregger H E, <i>Annis Geophys.,</i> 26 (1970), 547] are increased by a factor of 1'5; the neutral hydrogen densities in Jacchia model [Jacchia L G, <i>Special rep. No.</i> 332, <i>Smithsonian Astrophysical Observatory, Cambridge, Massachusetts, </i>1971] are enhanced by a factor of 3; heating efficiency given by WE Swartz and J S Nisbet <i>(J. geophys. Res., </i>77 (1972), 6259] are increased by a factor of 2; the topside heat flux is taken to be 2 X 109 eV cm^-2 sec^-1 for daytime and zero for nighttime and the particle fluxes at the upper boundary of 1000km are taken to be zero both for day and night. For dynamical parameters, a northward (poleward) wind of 100 m sec^-1 for daytime, and a southward (equatorward) wind of 100 m sec^-1 along with an eastward electric field of 0.5 mV/m for night time are taken. Based on these best values of input parameters, model profiles are given both for day and night at Delhi for medium solar activity and equinox conditions.