Cool Stars 14 - Submitted Abstract # 246
This version created on 05 October 2006

Coronal Diagnostics of Pre-Main Sequence Stars in the ONC


Norbert S. Schulz, MIT
David P. Huenemoerder, MIT
Paula Testa, MIT
Kazunori Ishibashi, MIT
Joel H. Kastner, Rochester Institute of Technology
Claude R. Canizares, MIT

Many stellar studies have shown that coronal activity in late-type
stars is triggered by active magnetic fields generated by stellar
dynamos.  The coronal imprint is thought to be complex involving
anisotropic magnetic fields and stellar parameters such as rotation,
spectral type and age.  Although X-ray studies of late-type pre-main
sequence (PMS) stars have a long history, detailed X-ray spectral
diagnostics of PMS stars have been available only recently and have
been analyzed for isolated stars with rather uncertain evolutionary
relationships.  High resolution X-ray studies of coronal activity are
very difficult and while observations of single isolated stars provide
insight in individual properties, deep exposures of a large number of
sources allow a more systematic analysis of plasma properties in a
variety of closely related stars.  We use the high-resolution X-ray
spectrometers onboard Chandra to survey accretion and coronal
signatures of a coeval sample of mostly K- and M-type PMS stars.  The
survey utilizes archival data and a number of new observations, which
will be conducted within the next two years for a total exposure of
580  ks.  We use information from the deep COUP images to lay out the
strategy of the non-archival survey which then allows to scan a larger
area of the ONC core and include as many bright PMS stars as possible.
We also show preliminary results from high resolution X-ray spectra
provided by the archival (280  ks) portion of the survey.

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