| Abstract | PDF (1.29 MB) | PS (1.48 MB) | References | HTML | Online Material | Simbad Objects | NASA ADS Abstract Service |
A&A 453, 241-252 (2006)
DOI: 10.1051/0004-6361:20053663
X-ray and optical bursts and flares in YSOs: results from a 5-day XMM-Newton monitoring campaign of L1551
G. Giardino1, F. Favata1, B. Silva1, 2, G. Micela3, F. Reale4 and S. Sciortino31 Astrophysics Division - Research and Science Support Department of ESA, ESTEC, Postbus 299, 2200 AG Noordwijk, The Netherlands
e-mail: Giovanna.Giardino@rssd.esa.int
2 Centro de Astrofisica da Universidade do Porto, Rua das Estrelas, 4150-762 Porto, Portugal
3 INAF - Osservatorio Astronomico di Palermo, Piazza del Parlamento 1, 90134 Palermo, Italy
4 Dipartimento di Scienze Fisiche & Astronomiche, Sezione di Astronomia, Piazza del Parlamento 1, 90134 Palermo, Italy
(Received 20 June 2005 / Accepted 15 February 2006)
Abstract
We present the results of a five-day monitoring campaign
with XMM-Newton of six X-ray bright young stellar objects (YSOs) in
the star-forming complex L1551 in Taurus. All stars present
significant variability on the five-day time scale. Modulation of
the light curve on time scales comparable with the star's rotational
period appeared to be present in the case of one weak-lined T Tauri
star. Significant spectral variations between the 2000 and the
2004 observations were detected in the (unresolved) classical T Tauri binary system XZ Tau: a hot plasma component which was present in the X-ray spectrum in 2000 had significantly weakened
in 2004. As XZ Tau N was undergoing a strong optical outburst in
2000, which had terminated since then, we speculate on the possible
relationship between episodic, burst accretion, and X-ray heating.
The transition object HL Tau underwent a strong flare with a complex
temperature evolution, which is indicative of an event confined within a very
large magnetic structure (few stellar radii), similar to the ones
found in YSOs in the Orion Nebula Cluster.
Key words: stars: pre-main sequence -- X-rays: stars -- stars: coronae -- stars: circumstellar matter
© ESO 2006



Document 