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arXiv · 2504.13654

Study of Solar Energetic Particles: their Source Regions, Flares and CMEs during Solar Cycles 23-24

Abstract

In this work, we examine the association between solar active regions and 152 solar flares, coronal mass ejections, and solar energetic particle (SEP) events over solar cycles 23-24 (1997-2017). The CDAW center's GOES data in the energy channel >10 MeV (Major SEPs; solar proton events) with flux >= 10 pfu was used for our investigation. For the associated activities, we have analyzed the data from space born satellites namely: SOHO/LASCO and SDO/AIA. We found a moderate correlation (55 %) between SXR flux and sunspot area i.e., active regions with larger sunspot areas generally generate larger flares. We found that most of the SEPs are originated from the magnetically complex active regions i.e., hale class beta-gamma-delta and beta. Very few events were associated with unipolar active regions. Stronger GOES X-ray is linked to more impulsive events, as evidenced by the negative correlation (-0.40) between X-ray flux and SEP duration. In the active region beta-gamma-delta, the highest average SEP intensity (2051 pfu) was detected. In the data set used, only 10 % SEPs are found impulsive in nature, while the remaining 90 % are gradual in nature. All the impulsive events had SEP intensity less than 100 pfu and most of the CMEs associated with these events were decelerated CMEs. We discovered that the majority of faster CMEs are linked to the most complex magnetic active regions. This indicates that high speed CMEs are produced by magnetically complex active regions. We discovered that 58 SEP events in our data set are linked to accelerated CMEs, while 82 are linked to decelerated CMEs. The highest average CME width is found corresponding to magnetically most complex active regions beta-delta, gamma-delta, alpha-gamma-delta and beta-gamma-delta, which shows that large CMEs are the consequences of magnetically complex active regions.

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Raj Kumar, Ramesh Chandra, Bimal Pande, Seema Pande. 2025-04-18. Study of Solar Energetic Particles: their Source Regions, Flares and CMEs during Solar Cycles 23-24. https://arxiv.org/abs/2504.13654

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