Cool Stars 14 - Submitted Abstract # 49
This version created on 05 October 2006

X-ray activity of low-mass PMS stars in the Lupus 3 star-forming
complex


Philippe Gondoin, European Space Agency

I present analysis results of an XMM-Newton observation of the Lupus 3
region that contains a high proportion of young low mass T Tauri stars
in the Lupus star-forming complex.  The detected sources were
correlated with a list of Herbig-Haro objects and H alpha emission
stars that contains mainly classical T Tauri stars, with a catalogue
of weak-line T Tauri Stars and with a recent list of new low-mass
members of the Lupus 3 dark cloud found in a visible-light
spectroscopic survey.  Twenty-five X-ray sources have visible or
near-IR counterparts that are known as pre-main sequence stars.  Two
of these objects with mass estimates lower than 0.075 solar masses
have an X-ray luminosity comparable with that of flaring young brown
dwarfs.  The EPIC spectra of the X-ray brightest sources were fitted
using optically thin plasma emission models.  The large emission
measure of hot plasma may be caused by disruptions of magnetic fields
associated with an intense flaring activity, while the X-ray emission
from the ``cool'' plasma components may result from solar-type active
regions.

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