A NEW ANALYSIS OF THE BUTTERFLY DIAGRAM FOR SOLAR FILAMENTS

In this article we study the filament cycle on butterfly diagrams for each type of filament defined according to the Tandberg-Hanssen classi fication, which is based on the magnetic polarities of the unipolar ma gnetic regions adjacent to the filaments. It distinguishes between typ e A filaments, which are located on the same line of magnetic held rev ersal as the active regions, from the type B filaments that are not. A more in-depth analysis has led us to subdivide type A filaments into active region filaments (Aa), quiescent filaments (Aq) and polar filam ents (Ap). Type B filaments are the classical quiescent filaments (Bq) . We have developed butterfly diagrams for the Aq and Ap filaments tog ether, and separately for the Aa, and lastly for the Bq. Analyzing the ir time variation, we can see that their full cycle is of 22-yr durati on, made up of two 11-yr periods, in which the type B filaments of the first: 11-yr become the type A (all three types) of the following 11- yr, considering that the active regions are emerging now on these magn etic field polarity reversal lines.