Astron. Astrophys. 339, 497-506 (1998)

Doppler imaging of stellar surface structure

IX. A high-resolution image of the weak-lined T Tauri star HDE 283572 = V987 Tauri

K.G. Strassmeier ^{* 1} and J.B. Rice <sup>2

1</sup> Institut für Astronomie, Universität Wien, Türkenschanzstrasse 17, A-1180 Wien, Austria (strassmeier@astro.univie.ac.at)
² Department of Physics, Brandon University, Brandon, Manitoba R7A 6A9, Canada (rice@BrandonU.ca)

Received 21 July 1998 / Accepted 18 August 1998

Abstract

We present a Doppler image of the T Tauri star HDE 283572 from a set of high-quality spectroscopic line profiles and simultaneous multicolor photometry from October 1997. Additional photometry throughout the entire observing season was obtained with a robotic telescope and is used to determine the precise photometric period of 1.54950.0002 days that we interpret to be the stellar rotation period. Further relevant astrophysical parameters like mass, luminosity, radius, effective temperature, gravity, and elemental abundances are obtained and discussed. HDE 283572 shows one of the largest and coolest polar spots ever observed and confirms an earlier map by Joncour et al. from Pic-du-Midi data. We also compare our map with predicted magnetic flux-tube distributions from MHD simulations and suggest that the polar spot on HDE 283572 was possibly created by a strong poleward meridional flow.

Key words: stars: activity starspots stars: imaging stars: individual: HDE 283572 stars: late-type

* Visiting Astronomer, Canada-France-Hawaii Telescope, operated by the National Research Council of Canada, the Centre National de la Recherche Scientifique de France, and the University of Hawaii

SIMBAD Objects

Contents

• 1. Introduction: Surface imaging of T Tauri stars
• 2. New observations
  • 2.1. Photometry
  • 2.2. Spectroscopy
• 3. Absolute parameters for HDE 283572
  • 3.1. Brightness and luminosity
  • 3.2. Photometric period
  • 3.3. Rotational broadening and the stellar radius
  • 3.4. Effective temperature, gravity, and lithium abundance
  • 3.5. Space-motion components
• 4. A Doppler image for October 1997
• 5. Discussion and conclusions
• Acknowledgements
• References

© European Southern Observatory (ESO) 1998

Online publication: October 21, 1998
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