New Evidence for a Coronal Mass Ejection-driven High Frequency Type II Burst near the Sun


Corona, the outermost region of the Sun, is believed to be present from a heliocentric distance of ~1.01 R ⊙ (where R is the radius of the solar photosphere) to more than 1 AU. Being highly tenuous plasma medium, it harbours large scale structures, as multi-frequency observations reveal. One such powerful solar phenomenon is Coronal Mass Ejections (CMEs), which has radio signatures as Type II bursts. Type II solar radio bursts are considered to originate from plasma waves excited by magnetohydrodynamic (MHD) shocks and converted into radio waves at the local plasma frequency and/or its harmonics. They are the direct diagnostic of MHD shocks in the solar atmosphere.

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