New diagnostic methods for the D-region ionosphere in a case of EISCAT heating experiments

Kero, A.1, Vierinen, J.1, Virtanen, I.2, Enell, C.-F.1 and Turunen, E.1

1 Sodankylš Geophysical Observatory, Sodankylš, Finland
2 University of Oulu, Oulu, Finland

According to present models the EISCAT Heater Facility is capable of increasing the electron temperature by a factor of ten in the D-region ionosphere. However, this maximum effect has not been verified by any radar observation yet. This is mostly due to lack of appropriate incoherent scatter data analysis package for the heated D region. Here we introduce a new nonlinear MCMC fitting of the theoretical autocorrelation function to detected lag profiles. Prior estimates for the fitting parameters are obtained by using the Sodankylš Ion Chemistry (SIC) model. This method is applied for the previous Finnish EISCAT campaign in November 2006, where three dedicated heater and radar experiments were carried out in order to quantify the active heating effect. The standard EISCAT ARC-D program and a newly designed SIPPI experiment, which is based on the direct sampling of the backscattered signal, were used in turns for the VHF radar. All the three experiments were successful technically and in terms of geophysical conditions. Preliminary results are shown in this presentation.