Catalano, Santo

Contact Email:
Institute: Catania Astrophysical Observatory
First Coauthor: Grazia Umana
Institute: Institute of Radioastronomy, CNR
Second Coauthor: Brunella Cafra
Institute: Physics and Astronomy Dep. Catania University
Subject Area: Binary Stars: Interacting
Waveband: Multi-wavelength
Technique: Spectroscopy
Presentation: Poster Display
Title: A simultaneous H-alpha and radio flare on UX Ari
Abstract: We report the results of coordinated H$\alpha$ and radio observations of the RS CVn binary UX Ari. Spectrographic H$\alpha$ observations were carried out at the M.G. Fracastoro Station of Catania Astrophysical Observatory (Mt. Etna), while the radio (5 GHz) observations were obtained by using the 32m radio telescope at the Noto VLBI Station of Institute of Radioastronomy of C.N.R., from 11 to 18 October 2000. During this period the decay phase of giant flare was followed in both bands. On our knowledge, this is the first time that a simultaneous H$\alpha$ and radio flare was observed in UX Ari. The onset of the flare and the whole lightcurve in the radio could be established by combining the Noto data with Green Bank monitoring program data, estimating a total duration of the flaring period of, at least, 16 days. The chromosferic and coronal energy budget is estimated and typical spatial scale, magnetic field strenght and plasma parameters of the plasma are discussed.