X-ray and optical bursts and flares in YSOs colon results from a 5 days XMM-Newton monitoring campaign of L1551
Publication date: 02 June 2006
Authors: Giardino, G., et al.
Journal: Astronomy & Astrophysics
We present the results of a five-day monitoring campaign with xmm of six X-ray bright Young Stellar Objects 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 stars rotational period appear to be present in the case of one WTTS. The CTTS XZ~Tau is the only star showing significant spectral variations between the 2000 and the 2004 observations: a hot plasma component which was present in the X-ray spectrum in 2000 has disappeared. As XZ~Tau was undergoing a strong (EXor-like) optical outburst in 2000, which has since then terminated, we speculate on the possible relationship between episodic, burst accretion and X-ray heating. The transition object HL~Tau undergoes a strong flare with a complex temperature evolution, 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.Link to publication