Ionospheric D-region temperature relaxation and its influences on radio signal propagation after solar X-flares occurrence

摘要

In this paper our attention is focused on relations between radio signalpropagation characteristics and temperature changes in D-region af- ter solarX-flare occurrence. We present temperature dependencies of electron plasmafrequency, the parameter that describes medium conditions for prop- agation ofan electromagnetic wave, and the refractive index which describes how this wavepropagates. As an example for quantitative calculations based on obtainedtheoretical equations we choose the reaction of the D-region to the solarX-flare occurred on May 5 th, 2010. The ionospheric modelling is based on theexperimental data obtained by low ionosphere observations using very lowfrequency radio signal.