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arXiv · 0907.2777

Doppler Images and Chromospheric Variability of TWA 17

M. B. Skelly·Y. C. Unruh·J. R. Barnes·W. A. Lawson·J. -F. Donati·A. Collier Cameron
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Abstract

We present Doppler imaging and a Balmer line analysis of the weak-line T Tauri star TWA 17. Spectra were taken in 2006 with the UCL Echelle Spectrograph on the Anglo-Australian Telescope. Using least-squares deconvolution to improve the effective signal-to-noise ratio we produced a Doppler map of the surface spot distribution. This shows similar features to maps of other rapidly rotating T Tauri stars, i.e. a polar spot with more spots extending out of it down to the equator. In addition to the photospheric variability, the chromospheric variability was studied using the Balmer emission. The mean H-alpha profile has a narrow component consistent with rotational broadening and a broad component extending out to +/-220 km/s. The variability in H-alpha suggests that the chromosphere has at least one slingshot prominence 3 stellar radii above the surface.

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M. B. Skelly, Y. C. Unruh, J. R. Barnes, W. A. Lawson, J. -F. Donati, A. Collier Cameron. 2009-07-16. Doppler Images and Chromospheric Variability of TWA 17. https://doi.org/10.1111/j.1365-2966.2009.15411.x

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