Modeling of oblique back scatter sounding signal of SuperDARN radar in the presence of travelling medium-sized inhomogeneity during the meteoroid “Chelyabinsk” impact

The study interprets phenomenon observed on 15 February 2013 with SuperDARN radar after the meteoroid “Chelya-binsk” explosion and fall. Comparison with adjacent magnetically-quiet days showed that after the impact, the oblique back scatter sounding (OBSS) signal reveals components which confirm the occurrence of additional travelling zones of signal focusing. The method for modeling focusing zones of OBSS signal is described. Comparing the modeling and experimental results allowed us to estimate basic parameters of ionospheric plasma travelling inhomogeneities possibly caused this effect. The modeling showed that experimental peculiarities of OBSS signal can be caused by radial motion of two inhomogeneities which have velocities of 400 and 220 m/s and centre close to meteoroid explosion spot. The modeling makes it possible to suggest that at distances up to 1000 km from the explosion centre, those inhomogeneities manifested themselves both in E and F ionospheric layers, while at distances more than 1000 km this occurs only in F layer.