Cool Stars 14 - Submitted Abstract # 171
This version created on 05 October 2006

Newly discovered multiple systems in the RasTyc sample


Alexis Klutsch, Observatoire Astronomique de Strasbourg
Antonio Frasca, INAF - Osservatorio Astrofisico di Catania
Patrick Guillout, Observatoire Astronomique de Strasbourg
Beppe Mignemi, INAF - Osservatorio Astrofisico di Catania
Rubens Freire Ferrero, Observatoire Astronomique de Strasbourg
Ettore Marilli, INAF - Osservatorio Astrofisico di Catania

We report on a follow-up program which aims at obtaining complete
radial velocity curves and solving the orbits of multiple systems
discovered in the RasTyc sample resulting from the cross-correlation
of ROSAT All-Sky Surveys (RASS) and TYCHO catalogues.  In particular,
we report on the discovery of new late-type triple systems and
spectroscopic binaries.  The knowledge of the incidence of binaries or
multiple systems in this sample is of paramount importance to study
the recent local star formation history using ROSAT and/or XMM-Newton
data.  Moreover, the incidence of triple systems in our sample,
compared to non X-ray selected samples, raises the questions of their
dynamical stability on a long time scale and the processes of close
binary formation.

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