Hemispheric Asymmetry of Coronal Mass Ejections with Different Angular Widths During Solar Cycles 23–25

Abstract The angular width of coronal mass ejections (CMEs) reflects their eruption scale, dynamics, and potential geoeffectiveness. To deepen our understanding of the hemispheric distribution characteristics of CME activities, we systematically investigate the north–south asymmetry of CMEs with different angular widths. Based on the white-light CME catalog from the Coordinated Data Analysis Workshop during solar cycles 23–25, our main results are as follows: (1) the temporal evolution of CME activity across solar cycles is primarily governed by normal and partial-halo CMEs, while narrow CMEs contribute relatively little to the overall variation; (2) CME activity in cycles 23 and 25 exhibits similar hemispheric patterns, with both cycles showing southern hemisphere dominance, in contrast to the northern dominance observed in cycle 24 (this difference may be attributed to the weaker heliospheric pressure during cycle 24); (3) the phase lag between CME activities in the two hemispheres is generally within five months. These findings reveal the solar activity cycle evolution of CME angular width distributions and hemispheric asymmetries, providing new physical constraints for understanding interhemispheric coupling in solar dynamo processes and improving space weather forecasting models.