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Stellar Coronal Spectroscopy with the Chandra HETGS

David P. Huenemoerder·Bram Boroson·Norbert S. Schulz·Claude R. Canizares·Derek L. Buzasi·Heather L. Preston·Joel H. Kastner
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Abstract

Spectroscopy with the Chandra High Energy Transmission Grating Spectrometer provides details on X-ray emission and activity from young and cool stars through resolution of emission lines from a variety of ions. We are beginning to see trends in activity regarding abundances, emission measures, and variability. Here we contrast spectra of TV Crt, a weak-lined T Tauri star, with TW Hya, a Classical T Tauri star. TV Crt has a spectrum more like magnetic activity driven coronae, relative to the TW Hya spectrum, which we have interpreted as due to accretion-produced X-rays. We have also observed the long period system, IM Pegasi to search for rotational modulation, and to compare activity in a long period active binary to shorter period systems and to the pre-main sequence stars. We detected no rotational modulation, but did see long-duration flares.

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David P. Huenemoerder, Bram Boroson, Norbert S. Schulz, Claude R. Canizares, Derek L. Buzasi, Heather L. Preston, Joel H. Kastner. 2003-10-11. Stellar Coronal Spectroscopy with the Chandra HETGS. https://arxiv.org/abs/astro-ph/0310319

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