Cool Stars 14 - Submitted Abstract # 215
This version created on 05 October 2006

High-resolution X-ray Spectroscopy of the Nearby T Tauri Star System
Hen 3-600


Joel Kastner, Rochester Institute of Technology
David Huenemoerder, MIT
Paola Testa, MIT
Norbert Schulz, MIT
David Weintraub, Vanderbilt University

We present Chandra High Energy Transmission Gratings (HETG)
spectroscopy of the multiple T Tauri star system Hen 3-600.  Hen 3-600
is a member of the nearby (D ~ 50  pc) TW Hya Association (TWA), and
is the third TWA member (after TW Hya itself and HD 98800) to be
observed by Chandra/HETG.  The two principle (M3) binary components of
Hen 3-600  are separated by 1.4'' and are marginally to well resolved
in the HETG data.  The X-ray flux of component Hen 3-600A, which
displays a mid-infrared excess indicative of the presence of a dusty
circumstellar disk, is a factor ~2-3 smaller than that of Hen 3-600B.
This difference is likely the result of a large flare at Hen 3-600B
during our observation.  We discuss the various plasma temperature and
density diagnostics available in the high-resolution spectra of Hen
3-600A, Hen 3-600B, and the combined system, and compare these results
with those previously obtained for TW Hya, HD 98800, and a handful of
other pre-main sequence systems.  As in other, key respects (e.g., UV
excess, H-alpha line intensities), the individual and composite X-ray
line spectra of Hen 3-600  indicate that its components (Hen 3-600A in
particular) are transition objects, with emission signatures that lie
between those of rapidly accreting, classical T Tauri stars (e.g., TW
Hya and BP Tau) and those of apparently nonaccreting, weak-lined T
Tauri systems (e.g., HD 98800  and AU Mic).

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