EDP Sciences
Free access
Volume 406, Number 1, July IV 2003
Page(s) L15 - L18
Section Letters
DOI http://dx.doi.org/10.1051/0004-6361:20030837

A&A 406, L15-L18 (2003)
DOI: 10.1051/0004-6361:20030837


Interferometry and asteroseismology: The radius of $\tau$ Cet

F. P. Pijpers1, T. C. Teixeira2, 3, P. J. Garcia2, 4, M. S. Cunha2, M. J. P. F. G. Monteiro2, 5 and J. Christensen-Dalsgaard1, 3

1  Theoretical Astrophysics Center (TAC), Department of Physics and Astronomy, Aarhus University, Ny Munkegade, 8000 Århus C, Denmark
    e-mail: fpp@phys.au.dk;jcd@phys.au.dk
2  Centro de Astrofísica da Universidade do Porto, Rua das Estrelas, 4150-762 Porto, Portugal
    e-mail: pgarcia@astro.up.pt;tct@phys.au.dk;mcunha@astro.up.pt;mjm@astro.up.pt
3  Department of Physics and Astronomy, Aarhus University, Denmark
4  Faculdade de Engenharia da Universidade do Porto, Portugal
5  Dept. de Matemática Aplicada da Faculdade de Ciências da Universidade do Porto, Portugal

(Received 17 April 2003 / Accepted 4 June 2003 )

We have determined from interferometry the radius of the nearby star $\tau$ Cet, using recent observations with the VINCI instrument on VLTI using the siderostats. The limb-darkened disk diameter is determined, with an unprecedented internal precision of  $0.5\%$, to be $1.971 \pm
0.009_{\rm (int.)}\pm 0.05_{\rm (ext.)}\,$ mas, corresponding to a physical radius of $0.773
\pm 0.004_{\rm (int.)}\pm 0.02_{\rm (ext.)}~{R}_\odot$ . With this determination $\tau$ Cet becomes a prime target for asteroseismic campaigns to determine its internal structure, and thereby test stellar evolution theory. We discuss implications for asteroseismology and present predictions for oscillation properties.

Key words: stars: fundamental parameters -- stars: oscillations -- stars: evolution -- stars: individual: $\tau$ Cet

Offprint request: F. P. Pijpers, fpp@phys.au.dk

SIMBAD Objects

© ESO 2003