Quantitative analysis of CME-Flare Coupling and their influence on Solar Energetic Particle Events (1997-2024)

Abstract

Solar energetic particles (SEPs) are major contributors to space weather conditions, especially protons with energies greater than 10 MeV, because they provide a critical scientific insight about the solar interplanetary processes. the relation between SEP flux and solar drivers (i.e., coronal mass ejections (CMEs) and solar flares) is discussed. For this, data collected between 1997-2024 were used; a total of 140 events were identified during this period, out of which around 75 % SEP events are linked with Halo CMEs. SC 23 has the most SEP events (87), followed by SC 24 (40) and SC 25 (13). Also, the study of the occurrence of SEP events with CME speed reveals that approximately 52 % SEP events were associated with fast CMEs (Speed>1400 km/s), 28 % with moderate CMEs (1000–1400 km/s), and approximately 20 % with slowspeed CMEs (Speed<1000 km/s). When the relationship between SEP events and CME-associated solar flares was investigated, it was found that more than 70 % of SEP-flare-related events originated from the western solar hemisphere, 30 % originated from the eastern hemisphere, and almost equal numbers of the SEP events are associated with northern and southern hemisphere-oriented solar flares. It was also found that approximately 50 % of SEP events are associated with M-class solar flares, 29 % with X-class solar flares and only 21% with C-class solar flares.  Finally, Regression and correlation analyses were conducted between the CME speeds and SEP Flux intensities, and separate fitted regression lines for each cycle indicate that they are in favour of the evident trend of a larger SEP flux with a faster CME speed and reflect a progressively stronger correlation. These findings illustrate that the CME dynamics and flare properties play a strong role in SEP production and propagation. For efficient space weather forecasting and satellite protection, it is important to monitor the real-time solar flare locations and CME parameters.