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arXiv · 2410.00787

CME-associated type-IV radio bursts: The solar paradigm and the unique case of AD Leo

Atul Mohan·Nat Gopalswamy·Surajit Mondal·Anshu Kumari·Sindhuja G
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Abstract

The type-IV bursts, associated with coronal mass ejections (CMEs), occasionally extend to the decameter-hectrometric (DH) range. We present a comprehensive catalog of simultaneous multi-vantage point observations of DH type-IV bursts by Wind and STEREO spacecraft since 2006. 73% of the bursts are associated with fast ($> 900\,km\,s^{-1}$) and wide ($>60^0$) CMEs, which are mostly geoeffective halo CMEs. Also, we find that the bursts are best observed by the spacecraft located within $|60^0|$ line of sight (LOS), highlighting the importance of LOS towards active latitudes while choosing target stars for a type-IV search campaign. In young active M dwarfs, CME-associated bursts have remained elusive despite many monitoring campaigns. We present the first detection of long-duration type-III, type-IV, and type-V bursts during an active event in AD Leo (M3.5V; $0.4M_\odot$). The observed burst characteristics support a multipole model over a solar-like active region magnetic field profile on the star.

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Atul Mohan, Nat Gopalswamy, Surajit Mondal, Anshu Kumari, Sindhuja G. 2024-10-01. CME-associated type-IV radio bursts: The solar paradigm and the unique case of AD Leo. https://arxiv.org/abs/2410.00787

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