On the source sizes of fine structures of type II radio bursts using LOFAR
Date:
The magnetic field dominates the structure and dynamics of the solar corona and it is the primary driver of Space weather. Radio observations are one of the most common approaches to diagnosing the magnetic field in the solar atmosphere. One of the direct signatures of explosive solar phenomena, such as coronal mass ejections (CMEs) in radio wavelengths, is called metric type II radio bursts. Type II bursts originate from plasma waves converted into radio waves at the local plasma frequency and its harmonics. These radio bursts can be considered a direct diagnosis of MHD shocks in the solar atmosphere. These bursts can be used to study the kinematics, energetics, and dynamics of the associated eruptive events. With state-of-the-art radio instruments such as LOw Frequency ARray (LOFAR), it has now been possible to study these bursts and the structures within them in great spectral, temporal and spatial resolutions. We studied the source sizes and shapes of the fine structures of type II radio bursts observed with LOFAR and their variation with frequency in metric wavelengths.