Ion Composition Measurements and Modelling at Altitudes from 140 to 350 km Using EISCAT Measurements

• Main Authors: A. Litvine, W. Kofman, B. Cabrit
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 1998
• Subjects: EISCAT
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.11.45; http://iss.bu.edu/students/litvin/Publications/./cephag_EISCAT.pdf

This work aims at processing the data of CP1 and CP2 programs of EISCAT ionospheric radar from 1987 to 1994 using the "full prole" method which allows to solve the "temperature-composition" ambiguity problem in the lower F region. The program of data analysis was developed in the CEPHAG in 19951996. To improve this program, we implemented another analytical function to model the ion composition prole. This new function better reects the real prole of the composition. Secondly, we chose the best method to select the initial conditions for the "full prole" procedure. A statistical analysis of the results was made to obtain the averages of various parameters: electron concentration and temperature, ion temperature, composition and bulk velocity. The aim is to obtain models of the parameter behaviour dening the ion composition proles : z 50 (transition altitude between atomic and molecular ions) and dz (width of the prole), for various seasons and for high and low solar activities. These models are then compared to other models. To explain the principal features of parameters z 50 and dz, we made an analysis of the processes leading to composition changes and related them to production and electron density prole. A new experimental model of ion composition is now available.