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Title: Imaging and Radio Signatures of Shock–Plasmoid Interaction
Understanding how shocks interact with coronal structures is crucial for understanding the mechanisms of particle acceleration in the solar corona and inner heliosphere. Using simultaneous radio and white-light observations, we investigate the interaction between a coronal mass ejection (CME)-driven shock and a plasmoid. LASCO and STEREO-A COR-2 white-light images are analyzed to track the evolution of the plasmoid, CME, and its associated shock, while the Wind/WAVES and STEREO/WAVES dynamic spectra provide complementary radio signatures of the shock–plasmoid interaction at ≈7R⊙. An interplanetary type II radio burst was detected as the shock propagated through the plasmoid. The merging of the plasmoid into the CME was accompanied by interplanetary type III radio bursts, suggesting escaping electron beams during the reconnection process. These observations clearly demonstrate that shock–plasmoid interactions can enhance the efficiency of particle acceleration associated with CMEs, with implications for electron acceleration in flare and heliospheric current sheets as well.  more » « less
Award ID(s):
2229336
PAR ID:
10674071
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
AAS
Date Published:
Journal Name:
The Astrophysical Journal Letters
Volume:
991
Issue:
1
ISSN:
2041-8205
Page Range / eLocation ID:
L3
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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