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The Coronal X-ray Spectrum of the Multiple Weak-Lined T Tauri Star System HD 98800

Joel H. Kastner·David P. Huenemoerder·Norbert S. Schulz·Claude R. Canizares·Jingqiang Li·David A. Weintraub
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Abstract

We present high-resolution X-ray spectra of the multiple (hierarchical quadruple) weak-lined T Tauri star system HD 98800, obtained with the High Energy Transmission Gratings Spectrograph (HETGS) aboard the Chandra X-ray Observatory (CXO). In the zeroth-order CXO/HETGS X-ray image, both principle binary components of HD 98800 (A and B, separation 0.8'') are detected; component A was observed to flare during the observation. The infrared excess (dust disk) component, HD 98800B, is a factor ~4 fainter in X-rays than the apparently ``diskless'' HD 98800A, in quiescence. The line ratios of He-like species (e.g., Ne IX, O VII) in the HD 98800A spectrum indicate that the X-ray-emitting plasma around HD 98800 is in a typical coronal density regime (log n <~ 11). We conclude that the dominant X-ray-emitting component(s) of HD 98800 is (are) coronally active. The sharp spectral differences between HD 98800 and the classical T Tauri star TW Hya demonstrate the potential utility of high-resolution X-ray spectroscopy in providing diagnostics of pre-main sequence accretion processes.

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Joel H. Kastner, David P. Huenemoerder, Norbert S. Schulz, Claude R. Canizares, Jingqiang Li, David A. Weintraub. 2004-03-02. The Coronal X-ray Spectrum of the Multiple Weak-Lined T Tauri Star System HD 98800. https://doi.org/10.1086/420769

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