Powerful flaring configurations in solar active regions: magnetic topology via special features of delta-structure phenomenon. I. Basic principles of topological model

Abstract

The close connection of magnetic field structure on the one hand and observable features of complex ARs with high flare efficiency on the other one is investigated in frames of so-called dynamic classification of flaring magnetic configurations (FMC) and the simple topological model of interacting magnetic complexes (IMC) suggested by Ikhsanov (1982). The primary objective of the present work is to expose general statements of the specified model and classification, the secondary one assumes the critical analysis and logical generalization of several important regularities being frequently observable in evolution stages of a typical complex AR with powerful flares including proton ones. Those cases are basically examined where the development of photospheric situation was marked by the formation of delta-configuration phenomenon described by Kunzel (1960) as one of the most impressive precursors of high flare activity. Without trying to use any additional assumptions and alternative hypotheses, the qualitative analysis of physical reasons and formative conditions of various delta-configuration classes in solar ARs is carried out. An attempt to construct the non-contradictory physical interpretation of morphological, flare-productive and magnetic features of such configurations is also done. In fact, the authors intend to demonstrate that the analysis of delta-structure phenomenon from the IMC-based point of view allows to explain well many early established regularities as kindred phenomena having the uniform physical reason.