The Evolution of Vector Magnetic Fields and the Origin of Coronal Mass Ejections (CMEs)

Coronal mass ejections (CMEs) are intrinsically associated with magnetic structures and evolutions in the solar photosphere. Based on the analysis of vector magnetic field data, we found that: 1, magnetic flux cancellation is the most universal magnetic change in the course of CME onset; 2, new flux emergence also plays an important role in CME origination; 3, interaction and reconnection of flux systems with opposite sign helicity is another key element in the magnetism of CME initiation.