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arXiv · 2611.04833

Solar extreme-ultraviolet waves and other associated solar activities

Apoorv Dashora·Ramesh Chandra·Pooja Devi
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Abstract

Extreme ultraviolet (EUV) waves are large-scale, tsunami like disturbances on the solar surface associated with eruptive phenomena such as solar flares, filament eruptions, and coronal mass ejections (CMEs). Because their strong correlation with major solar eruptions, we present here a comprehensive statistical study of EUV waves and their connections to Moreton waves, CMEs, solar flares, type II radio bursts, and solar energetic particle (SEP) events during Solar Cycle 25 (December 2019-December 2025). This study utilizes EUV data from the Atmospheric Imaging Assembly onboard the Solar Dynamics Observatory and coronagraph data from the Large Angle and Spectrometric Coronagraph onboard Solar and Heliospheric Observatory. Our analysis reveals that 12.3% of the observed EUV waves are associated with Moreton waves, 95% with CMEs, 92.7% associated with flares, 44.3% with metric type II radio bursts, and 11.8% with SEPs. While nearly all EUV waves are linked to CMEs, their association with solar flares varies significantly, ranging from weak B-class events to major X-class flares. Furthermore, the majority of Moreton waves correlate with large- or medium-class flares, with only a small fraction associated with weaker C-class flares. Our findings may contribute to a better understanding of space weather events and, potentially, to their forecasting.

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Apoorv Dashora, Ramesh Chandra, Pooja Devi. 2026-11-03. Solar extreme-ultraviolet waves and other associated solar activities. https://arxiv.org/abs/2611.04833

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