Research on stellar activity at Catania University and Astrophysical Observatory is supported by MURST (Ministero dell'Università e della Ricerca Scientifica e Tecnologica ). This research has made use of SAXDAS linearized and cleaned event files (Rev.1.1) produced at the Beppo-SAX Science Data Center. We would thanks L. Chiappetti G. Cusumano and G. Tagliaferri for useful and precious suggestions and discussions, and J.L. Linsky for his comments and suggestions. We are also indebted with A. Antonelli and F. Fiore of Beppo-SAX Science Data Center for having helped us in data reduction. Finally, we would extend our thanks to HEASARC people for the support they give with FTOOLS and XANADU software.
© European Southern Observatory (ESO) 1999
Online publication: June 17, 1999