Solar Differential Rotation Study Based on SDO/AIA Ultraviolet Images

The differential rotation of the Sun is a key mechanism for converting polar magnetic fields into toroidal magnetic fields. We used the flux modulation method to study the differential rotation of the Sun based on the full-disk ultraviolet images at 1600 Å, etc. from the Atmospheric Imaging Assembly (AIA) of the Solar Dynamics Observatory (SDO). First, the full-disk images were preprocessed and divided into different latitude regions. Then, after data processing, the flux time series of each latitude region were obtained. Finally, autocorrelation analysis was performed on the flux time series of each latitude region to obtain the rotation period and angular velocity of rotation at different latitudes. Research findings indicate that within the latitude range of 80°S to 80°N, the solar angular velocity of rotation varies as a function of latitude. Across different AIA wavelengths, the equatorial angular velocity of rotation increases with height, while the differential rotation degree decreases. The average angular velocity of rotation and differential rotation degree near the equator show no significant correlation with the solar activity cycle.