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arXiv · 1408.3049

HST FUV monitoring of TW Hya

H. M. Günther·N. S. Brickhouse·A. K. Dupree·S. J. Wolk·P. C. Schneider·G. J. M. Luna
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Abstract

Classical T Tauri stars (CTTS) are young (< 10 Myr), cool stars that actively accrete matter from a disk. They show strong, broad and asymmetric, atomic FUV emission lines. Neither the width, nor the line profile is understood. Likely, different mechanisms influence the line profile; the best candidates are accretion, winds and stellar activity. We monitored the C IV 1548/1550 Ang doublet in the nearby, bright CTTS TW Hya with the Hubble Space Telescope Cosmic Origin Spectrograph (HST/COS) to correlate it with i) the cool wind, as seen in COS NUV Mg II line profiles, ii) the photometric period from joint ground-based monitoring, iii) the accretion rate as determined from the UV continuum, and iv) the Ha line profile from independent ground-based observations. The observations span 10 orbits distributed over a few weeks to cover the typical time scales of stellar rotation, accretion and winds. Here we describe a model with intrinsically asymmetric C IV lines.

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H. M. Günther, N. S. Brickhouse, A. K. Dupree, S. J. Wolk, P. C. Schneider, G. J. M. Luna. 2014-08-13. HST FUV monitoring of TW Hya. https://arxiv.org/abs/1408.3049

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