STOCHASTICITY AND PERSISTENCE OF SOLAR CORONAL MASS EJECTIONS

The study of the statistical properties of coronal mass ejections (CMEs) reveals that their properties depend on the period of solar activity. In particular, when investigating the origin of the waiting time distribution between CMEs, a significant departure from a Poisson process during periods of high solar activity has been found, thus suggesting the existence of at least two physical processes underlying the origin of CMEs. One acts continuously, perhaps related to randomly occurring magnetic reconfigurations of the solar corona at large scales. The other plays a role only during the solar maximum, probably due to the photospheric emergence of magnetic flux as a statistically persistent mechanism, which generates long correlation times among CME events strong enough not to be destroyed by the former random process