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Astron. Astrophys. 337, 413-420 (1998)

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X-ray spectroscopy of the weak-lined T Tauri star HD 283572

F. Favata 1, G. Micela 2 and S. Sciortino 2

1 Astrophysics Division - Space Science Department of ESA, ESTEC, Postbus 299, 2200 AG Noordwijk, The Netherlands
2 Osservatorio Astronomico di Palermo, Piazza del Parlamento 1, I-90134 Palermo, Italy

Received 2 April 1998 / Accepted 3 June 1998


We have analyzed the existing X-ray spectroscopic data for the Weak-Line T Tauri star (WTTS) HD 283572, from the ROSAT, ASCA and SAX satellites. All the data sets are well fit with an absorbed two-temperature model based on collisional ionization equilibrium. Together with the Einstein data discussed in the literature, these data sets afford a 16.5 years time span, allowing to study the short- and long-term spectroscopic and photometric variability characteristics of the X-ray emission from WTT stars. The X-ray luminosity of HD 283572 appears to vary by factors of [FORMULA] on time scales of tens of kiloseconds, within a single observations, while its average X-ray luminosity has varied by a factor of [FORMULA] (peak-to-peak) along the 16.5 yr studied here. The SAX observation also shows evidence for a short flare, with an enhancement of the X-ray luminosity by a factor of [FORMULA].

Key words: stars: individual: HD 283572 – stars: late-type – stars: activity – stars: coronae – X-rays: stars

Send offprint requests to: F. Favata
Correspondence to: ffavata@astro.estec.esa.nl

© European Southern Observatory (ESO) 1998

Online publication: August 17, 1998