The Criteria for Homologous Radio Events Associated With Flares


M. Vukićević-Karabin, M. Dimitrijević




Though Waldmeier in 1938 as well as Dodson and Hedeman in 1949 already perceived that some solar flares were repeating for more days at the same spot exactly, the idea of homology for optical flares had been introduced by Ellison, Mc Kenna and Reid in 1960 (1). They defined them as: "...s flares which occur successively in the same active region, correspond in position to the local sunspots and show a common pattern and development". Fokker and Roosen (2) extended the concept of homology to the flare associated radio events as well. In his later work (1967) Fokker (3) gave some additional informations and a criterion of homology for radio events. In 1969 Pinter (4) indicated the existence of homology for solar x-ray burst. In 1970 White and Janssens (5) confirmed Fokker's assumption that the optical homologous flares are associated with homologous radio events. Gopala Rao reached the same conclusion in 1970 (6). Studying the relationship between optical flares and radio events the cited authors (5,6) observed that there had been some inadequacies in the definition of homology in the radio domain though they did not exhibit precisely where the problem is neither gave some suggestion for solving it. The purpose of this contribution is to derive a conclusion by analysing the homologous radio events as to what are the strong and weak points of Fokker's criteria. In addition, an attempt has been made to improve these criteria by introducing certain contributions.