Statistical Analysis of Associated and Non Associated Type II Solar Radio Bursts during the Decreasing Phase of Solar Cycle 23

摘要

Type II and Type III bursts are probably the most intensively studied form of radio emission in all of astrophysics. Immense effort has gone into the elucidation of both the observational and theoretical aspects. The bursts have captured the attention of plasma theorists because a considerable body of information exists on the plasma parameters and there is adequate space and time in the solar corona for the evolution of various particle and wave processes. Type II radio bursts are indicative of shock propagation in the corona and inner heliosphere, accompanied by electron acceleration. They are good indicators of shocks that eventually cause sudden commencement of geomagnetic storms. In our work, we have studied the type II bursts and their association with type III bursts during the decreasing phase after the peak phase of solar cycle 23. For the period 2002-2004, type II and type III bursts data of Culgoora observatory is referred. The parameters such as duration drift rate, shock speed, band width of these associatedon associated bursts are compared. Results indicate that except in the case of duration and bandwidth, the above parameters almost remain uniform for associated and non associated type II bursts.