Горизонтальная составляющая течений фотосферной плазмы при возникновении активных областей на Солнце

Abstract

The dynamics of horizontal photospheric plasma flows during the first hours of the emergence of active regions in the solar photosphere have been analyzed using SOHO/MDI data. Four active regions emerging near the solar limb have been considered. It has been found that extended regions of high Doppler velocities with different signs are formed during the magnetic flux emergence in the horizontal velocity field. The flows form at the beginning of the emergence of active regions and are present for a few hours. The peak values of the mean (inside the ±500 m/s isolines) and maximum Doppler velocities are 800–970 m/s and 1410–1700 m/s, respectively. The asymmetry was detected between velocity structures of leading and following polarities. Velocity structures located in a region of leading magnetic polarity are more powerful and exist longer than those in regions of following polarity. The asymmetry for the mean and maximal Doppler velocities reach 240–460 m/s and 710–940 m/s, respectively. An interpretation of the observable flow of photospheric plasma is given.