Complex network view to solar flare asymmetric activity

Abstract

Asymmetric behavior of the solar hemispheres is an essential aspect of the activity. This paper uses a complex network approach to study the solar flare asymmetric activity in two hemispheres. We construct a network based on the locations and flare flux (GOES flux classification) from 2008 December to 2019 December for 4033 and 4725 flares on the north and south hemispheres, respectively. We apply the visibility graph analysis to construct the networks for different spatial (HEALPix pixelization) constraints. The HEALPix Mollweide projection maps show the nodes with a considerable degree and clustering coefficients in low latitudes in the southern hemisphere. The northern hemisphere network exhibits more hubs (the nodes with the highest connectivity, closeness, betweenness, and Pagerank) than the south. The locations of identified hubs can indicate regions with high magnetic activity. Identifying active areas of the sun is one of the essential issues in space weather science. We explore the small-world and scale-free characteristic of the flare complex network that indicates the flares form a system of self-organized criticality and each flare has an influential role in occurring subsequent flares on the solar surface.