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arXiv · 2503.13876

On Using Gradient Dynamic Spectra (GraDS) to Study Type-II Solar Radio Bursts

Puja Majee·Devojyoti Kansabanik·Divya Oberoi
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Abstract

Solar type-II radio bursts are coherent plasma emissions arising from magnetohydrodynamic shocks produced by either coronal mass ejections (CMEs) or flares. Type-II bursts sometimes show split-band emissions in the dynamic spectrum. When these split-band emissions come from regions just upstream and downstream of the shock, type-II band-splitting can be used as an important tool for estimating magnetic fields at the shock front. Earlier studies have shown that only $\sim$20\% of the type-IIs show morphologically similar split-bands. Imaging studies can unambiguously identify such instances, though they remain very rare. Here we suggest a useful approach to augment dynamic spectra-based studies by also examining the Gradient Dynamic Spectra (GraDS) of type-II emission. We also verified the conclusions of this approach against those from an imaging study.

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Puja Majee, Devojyoti Kansabanik, Divya Oberoi. 2025-03-18. On Using Gradient Dynamic Spectra (GraDS) to Study Type-II Solar Radio Bursts. https://arxiv.org/abs/2503.13876

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