Irkutsk, Russian Federation
Irkutsk, Russian Federation
Irkutsk, Russian Federation
UDK 52 Астрономия. Астрофизика. Исследование космического пространства. Геодезия
GRNTI 41.21 Солнце
OKSO 03.06.01 Физика и астрономия
BBK 223 Физика
TBK 6143 Астрофизика. Радиоастрономия
BISAC SCI005000 Physics / Astrophysics
We study the evolution of the photospheric magnetic field at the early stage of active region development. We use data on longitudinal component of the magnetic field and line-of-sight velocities from SOHO/MDI and SDO/HMI. The visual inspection of 48 cases of birth of active regions and the detailed analysis of the magnetic flux dynamics in 4 active regions have shown that at the time of emergence of a new magnetic field, the field of the following polarity is the first to be detected in the photosphere. The flux asymmetry of the leading and following polarities persists for several tens of minutes. The observed asymmetry of magnetic fluxes supports the results of the numerical simulation of emergence of the active region magnetic field in the upper layers of the convective zone, which has been carried out by Rempel and Cheung [2014].
magnetic field, active regions
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