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A Hot Wind from the Classical T Tauri Stars: TW Hydrae and T Tauri

A. K. Dupree·N. S. Brickhouse·Graeme H. Smith·Jay Strader
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Abstract

Spectroscopy of the infrared He I (10830A) line with KECK/NIRSPEC and IRTF/CSHELL, and of the ultraviolet C III (977A) and O VI (1032A) emission with FUSE reveals that the classical T Tauri star TW Hydrae exhibits P Cygni profiles, line asymmetries, and absorption indicative of a continuous, fast (~400 km/s), hot (~300,000 K) accelerating outflow with a mass loss rate \~10^-11 - 10^-12 solar masses per year, or larger. Spectra of T Tauri N appear consistent with such a wind. The source of the emission and outflow seems restricted to the stars themselves. Although the mass accretion rate is an order of magnitude less for TW Hya than for T Tau, the outflow reaches higher velocities at chromospheric temperatures in TW Hya. Winds from young stellar objects may be substantially hotter and faster than previously thought.

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A. K. Dupree, N. S. Brickhouse, Graeme H. Smith, Jay Strader. 2005-05-02. A Hot Wind from the Classical T Tauri Stars: TW Hydrae and T Tauri. https://doi.org/10.1086/431323

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