A&A 488, L67-L70 (2008)
Centauri: a new binary Be star detected by VLTI/AMBER spectro-interferometryA. Meilland1, F. Millour1, Ph. Stee2, A. Spang2, R. Petrov2, D. Bonneau2, K. Perraut3, and F. Massi4
1 Max Planck Intitut fur Radioastronomie, Auf dem Hugel 69, 53121 Bonn, Germany
2 Laboratoire A.H. FIZEAU, UMR 6525, UNS/OCA/CNRS, Campus Valrose, 06108 Nice Cedex 2, France
3 Laboratoire d'Astrophysique de Grenoble, UMR 5571 Université Joseph Fourier/CNRS, BP 53, 38041 Grenoble Cedex 9, France
4 INAF – Osservatorio Astrofisico di Arcetri, Istituto Nazionale di Astrofisica, Largo E. Fermi 5, 50125 Firenze, Italy
Received 16 July 2008 / Accepted 29 July 2008
Aims. We study the Be star Cen circumstellar disk using long-baseline interferometry which is the only observing technique capable of resolving spatially and spectroscopically objects smaller than 5 mas in the H and K band.
Methods. We used the VLTI/AMBER instrument on January 6, 8, and 9, 2008, in the H and K bands to complete low (35) and medium (1500) spectral resolution observations.
Results. We detected an oscillation in the visibility curve plotted as a function of the spatial frequency which is a clear signature of a companion around Cen. Our best-fit soltution infers a binary separation of 68.7 mas, a companion flux contribution in the K band of about 7% of the total flux, a PA of 117.5, and an envelope flux around the Be primary that contributes up to about 50% of the total flux, in agreement with our Spectral Energy Distribution (SED) fit. The envelope size is estimated to be 1.6 mas in K but no departure from spherical symmetry is detected.
Key words: techniques: high angular resolution -- techniques: interferometric -- stars: emission-line, Be -- stars: binaries: close -- stars: winds, outflows -- stars: circumstellar matter
© ESO 2008