The objective of this article was to carry out a statistical study of the occurrences of CMEs from solar cycles 23 and 24 and to deduce interpretations as a contribution to a greater understanding of heliosphere dynam...The objective of this article was to carry out a statistical study of the occurrences of CMEs from solar cycles 23 and 24 and to deduce interpretations as a contribution to a greater understanding of heliosphere dynamics. Thus, from the statistical examination of the occurrences according to the phases it appeared that solar cycle 23 (SC23) counted 13207 occurrences of CMEs while 16510 were counted for solar cycle 24 (SC24). These occurrences of CMEs are correlated to the sunspot cycle because in each of these cycles we would note the predominance of the phase maximum (1478 for SC23 and 2338 for SC24) over the ascending phases (550 for SC23 and 1559 for the SC24) and descending (1197 for the SC23 and 1178 for the SC24) and these predominate on the minimum phase (206 for the SC23 and 834 for the SC24). However, the percentages per phase in each cycle show that SC23 was only predominant over SC24 at the maximum phase (43.08% for SC23 and 39.57% for SC24). From this correlation, some authors therefore suggest that the toroidal magnetic field would be the cause of the ejections of these CMEs. The annual statistical examination confirms the correlation with the sunspot cycle but nevertheless reveals in the descending phase of SC23 two unusual peaks in 2005 and 2007 and a drop-in sunspot activity of 42% from SC23 to SC24 while that we would note an increase in the activity of CME occurrences of 36% at SC24, thus suggesting that CMEs can occur without the toroidal magnetic field being the cause, particularly from the coronal holes. The seasonal statistical examination shows for its part that out of the total of 29717 occurrences of CMEs of the two cycles that spring (28%) was the most active than summer (25%) and summer over autumn (24%) and finally autumn over winter (23%) thus revealing that: The ascending phase of the cycle was only the most active during the winter seasons in spring and the descending phase only during the rest of the seasons. Finally, the monthly statistical examination of the occurrences of CMEs corroborates the seasonal statistical examination by the presence of two maximum peaks (May and October) and two minimum peaks (February and August).展开更多
文摘The objective of this article was to carry out a statistical study of the occurrences of CMEs from solar cycles 23 and 24 and to deduce interpretations as a contribution to a greater understanding of heliosphere dynamics. Thus, from the statistical examination of the occurrences according to the phases it appeared that solar cycle 23 (SC23) counted 13207 occurrences of CMEs while 16510 were counted for solar cycle 24 (SC24). These occurrences of CMEs are correlated to the sunspot cycle because in each of these cycles we would note the predominance of the phase maximum (1478 for SC23 and 2338 for SC24) over the ascending phases (550 for SC23 and 1559 for the SC24) and descending (1197 for the SC23 and 1178 for the SC24) and these predominate on the minimum phase (206 for the SC23 and 834 for the SC24). However, the percentages per phase in each cycle show that SC23 was only predominant over SC24 at the maximum phase (43.08% for SC23 and 39.57% for SC24). From this correlation, some authors therefore suggest that the toroidal magnetic field would be the cause of the ejections of these CMEs. The annual statistical examination confirms the correlation with the sunspot cycle but nevertheless reveals in the descending phase of SC23 two unusual peaks in 2005 and 2007 and a drop-in sunspot activity of 42% from SC23 to SC24 while that we would note an increase in the activity of CME occurrences of 36% at SC24, thus suggesting that CMEs can occur without the toroidal magnetic field being the cause, particularly from the coronal holes. The seasonal statistical examination shows for its part that out of the total of 29717 occurrences of CMEs of the two cycles that spring (28%) was the most active than summer (25%) and summer over autumn (24%) and finally autumn over winter (23%) thus revealing that: The ascending phase of the cycle was only the most active during the winter seasons in spring and the descending phase only during the rest of the seasons. Finally, the monthly statistical examination of the occurrences of CMEs corroborates the seasonal statistical examination by the presence of two maximum peaks (May and October) and two minimum peaks (February and August).
