Comparative Features of the North–South Asymmetry of Solar Activity According to Data on the Number and Magnetic Fluxes of Active Regions of Different Magnetic Morphology in the 23rd and 24th Cycles

Abstract

The characteristics of solar cycles important for the development of dynamo theory can manifest themselves differently when different activity indices are used. To study the features of the north–south (N–S) asymmetry of solar activity, a comparison was made of the time profiles of active regions (ARs) of the 23rd and 24th cycles based on data on their number (the most accessible and frequently used) and magnetic flux (allowing a more complete assessment about the generative function of the dynamo process). We used data on 3047 ARs that appeared on the disk from June 1996 to December 2020 according to the MMC ARs CrAO (magneto-morphological classification of ARs of the Crimean Astrophysical Observatory) catalog (http://sun.crao.ru/databases/catalog-mmc-ars). The attribution of AR to the classes of the regular and irregular sunspot groups was taken into account in accordance with the MMC ARs CrAO. Analysis of the results showed the following. Variations of ARs of both MMC classes are associated with a cycle, which confirms their relationship with the action of the global dynamo. Due to the overlap of multipeak ARs profiles of different classes, a classic double-peak cycle structure is formed in the two hemispheres. Variations in the relative position of profiles for the number and magnetic flux of ARs (for groups of each class in each hemisphere) during the cycle can be associated with changes in the sizes of ARs. This makes it possible to suggest the multicomponent nature of the dynamo process, which consists in joint manifestation of global (responsible for the production of ARs) and turbulent (associated with the fragmentation of magnetic structures due to turbulence in the convection zone) components of the dynamo. The strongest magnetic fluxes observed for the irregular groups in the maximum of the cycle may also indicate action of the turbulent component of the dynamo distorting the regular flux tube. The pronounced N–S asymmetry of these fluxes agrees with the hypothesis on the possibility of weakening of the toroidal field in one of the hemispheres due to the interaction of the dipole and quadrupole components.