Comparison of Features of the Generation of Coronal Mass Ejections with Variable Velocity in the Field of View of LASCO Coronagraphs
This paper compares features of the generation of coronal mass ejections (CMEs) with the lowest, intermediate, and highest velocities in the field of view of LASCO C2 and C3 coronagraphs found from an analysis of multi-wavelength data with high temporal and spatial resolution. The dynamics of the field characteristics in the umbra of sunspots of active regions (ARs) in which variable-velocity CMEs occur are compared based on SDO/HMI vector magnetic field measurements. It is found that there are almost no noticeable changes in field characteristics in the AR sunspots in which slow CMEs occur after the onset of the eruptive event. However, there are noticeable changes in the field intensity and inclination angles of the flux tube emerging from the umbra of the sunspot in some AR sunspots in which CMEs occur after the onset of the eruptive event. Thus, for the fast CME detected on January 7, 2014, the inclination angle of the flux tube from the umbra of one of the sunspots before the flare onset reached a maximum value of ≈4°. After the flare onset, it was less than 1°.
We are grateful to the teams of LASCO, SDO/AIA, SDO/HMI, and GOES for the opportunity to use data from these instruments. This work was supported by the Russian Foundation for Basic Research, project nos. 17-02-300 A and 15-02-01077 A. At the Institute of Solar–Terrestrial Physics of the Siberian Branch of the Russian Academy of Sciences, this work was performed with budgetary funding of Basic Research program II.16.
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