Theoretical modelling of the topside electron density distribution in the Indian equatorial and low latitude ionosphere using DU_LLTD Model

The spatial and temporal distribution of ionospheric electron density in the Indian equatorial and low latitudes during high solar activity conditions is theoretically simulated. The Dibrugarh University Low Latitude Temperature and Density (DU_LLTD) Model, which operates by simultaneously solving the time-dependent equations of continuity, momentum and energy balance equations along the ED (eccentric dipole) geomagnetic field lines (Bhuyan et al., 2001a,b) is used to generate the density profiles at different heights for solar maximum equinoctial condition. The effects of $\mathrm{E} \times \mathrm{B}$ drift, horizontal wind, magnetic field, solar activity, photoionization rate, chemical reactions and solar EUV flux are considered as inputs for the calculation of electron/ion density. Heating due to photoelectrons, collision between ions, ions and electrons, rotational heat transfer, vibrational heat transfer and thermal conductivity are considered for the calculation of electron and ion temperatures (Bhuyan et al., 2008).