An asymmetry detected in the disk of κ Canis Majoris with AMBER/VLTI
A. Meilland, F. Millour, P. Stee, A. Domiciano de Sousa Jr., R. G. Petrov, D. Mourard, S. Jankov, S. Robbe-Dubois, A. Spang, E. Aristidi, P. Antonelli, U. Beckmann, Y. Bresson, A. Chelli, G. Duvert, S. Gennari, P. Kern, S. Lagarde, E. Le Coarer, F. Lisi, F. Malbet, K. Perraut, P. Puget, A. Roussel, E. Tatulli, G. Weigelt, G. Zins, M. Accardo, B. Acke, K. Agabi, E. Altariba, B. Arezki, C. Baffa, J. Behrend, S. Bonhomme, S. Busoni, F. Cassaing, J.-M. Clausse, J. Colin, C. Connot, T. Driebe, P. Feautrier, D. Ferruzzi, T. Forveille, E. Fossat, R. Foy, D. Fraix-Burnet, A. Gallardo, E. Giani, C. Gil, A. Glentzlin, M. Heiden, M. Heininger, O. Hernandez, K.-H. Hofmann, D. Kamm, M. Kiekebusch, S. Kraus, D. Le Contel, J.-M Le Contel, T. Lesourd, B. Lopez, M. Lopez, Y. Magnard, A. Marconi, G. Mars, G. Martinot-Lagarde, P. Mathias, J.-L. Monin, D. Mouillet, E. Nussbaum, K. Ohnaka, J. Pacheco, C. Perrier, Y. D. Rabbia, S. Rebattu, F. Reynaud, A. Richichi, A. Robini, M. Sacchettini, D. Schertl, W. Solscheid, P. Stefanini, M. Tallon, I. Tallon-Bosc, D. Tasso, L. Testi, F. Vakili, J.-C. Valtier, M. Vannier, N. Ventura
Aims. We study the geometry and kinematics of the circumstellar environment of the Be star κ CMa in the Brγ emission line and its nearby continuum.
Methods. We use the AMBER/VLTI instrument operating in the K band, which provides a spatial resolution of about 6 mas with a spectral
resolution of 1500, to study the kinematics within the disk and to infer its rotation law. To obtain more kinematical constraints we also use a high
spectral resolution Paβ line profile obtain in December 2005 at the Observatorio do Pico do Dios, Brazil and we compile V/R line profile variations
and spectral energy distribution data points from the literature.
Results. Using differential visibilities and differential phases across the Brγ line we detect an asymmetry in the disk. Moreover, we found that
κ CMa seems difficult to fit within the classical scenario for Be stars, illustrated recently by α Arae observations, i.e. a fast rotating B star close to
its breakup velocity surrounded by a Keplerian circumstellar disk with an enhanced polar wind. We discuss the possibility that κ CMa is a critical
rotator with a Keplerian rotating disk and examine whether if the detected asymmetry can be interpreted within the “one-armed” viscous disk
Astronomy and Astrophysics
Volume 464, Page 73
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