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arXiv · 0706.3901

High-resolution Spectroscopy of [Ne II] Emission from TW Hya

Gregory J. Herczeg·Joan Najita·Lynne A. Hillenbrand·Ilaria Pascucci
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Abstract

We present high-resolution echelle spectra of [Ne II] 12.81 micron emission from the classical T Tauri star (CTTS) TW Hya obtained with MICHELLE on Gemini North. The line is centered at the stellar radial velocity and has an intrinsic FWHM of 21\pm 4 km/s. The line width is broader than other narrow emission lines typically associated with the disk around TW Hya. If formed in a disk, the line broadening could result from turbulence in a warm disk atmosphere, Keplerian rotation at an average distance of 0.1 AU from the star, or a photoevaporative flow from the optically-thin region of the disk. We place upper limits on the [Ne II] emission flux from the CTTSs DP Tau and BP Tau.

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Gregory J. Herczeg, Joan Najita, Lynne A. Hillenbrand, Ilaria Pascucci. 2007-06-26. High-resolution Spectroscopy of [Ne II] Emission from TW Hya. https://doi.org/10.1086/521545

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