Large-scale evolution of the active region noaa 7978 7981, 7986 observed by goes, SOHO, and Yohkoh

We took part in a joint project aimed to study the large-scale evolution of an active region from its emergence throughout its decay for several solar rotations. Our interest focuses on the understanding of how energy is generated, released, deposited, and transformed in active regions. To this end, we determined physical parameters like intensity, temperature, and emission measure of the whole active region as a function of time for the entire period selected. We present the preliminary results of the analysis of GOES (Geosynchronous Operational Environmental Satellite), SOHO (Solar and Heliospheric Observatory) and Yohkoh data of the active region named NOAA 7978, 7981, and 7986 observed between July and October 1996.