Studying magnetospheric disturbances accompanied by midlatitude coherent echo signals

The results of an analysis of midlatitude coherent echo, registered with the Irkutsk incoherent scatter radar during 53 observational seances, are presented. The observations continued for 4358 h from January 1998 to January 2005. Echo signals revealed during an analysis are divided into two groups with respect to power: strong (s) and weak (w) echoes. It was detected that echo signals with coherent echo characteristics are observed during all local time hours and at different levels of geomagnetic activity. The probability of s-echo appearance is minimal in noon hours and is maximal in post-midnight-morning hours. It has been indicated that the longest and strongest coherent echoes are observed at midlatitudes during great magnetic storms at an increased dynamic pressure of the solar wind.[PUBLICATION ABSTRACT]