Direct constraint on the distance of $\gamma^2$ Velorum from AMBER/VLTI observations

  title={Direct constraint on the distance of \$\gamma^2\$ Velorum from AMBER/VLTI observations},
  author={F. Millour and Romain G. Petrov and Olivier Chesneau and Daniel Bonneau and Luc Dessart and C. Bechet and I. Tallon-Bosc and Michel Tallon and Eric Thi'ebaut and Farrokh Vakili and Fabien Malbet and Denis Mourard and G{\'e}rard Zins and Alain Roussel and Sylvie Robbe-Dubois and Pascal Puget and K. Perraut and Franco Lisi and Etienne Le Coarer and St'ephane Lagarde and Pierre Y. Kern and Laurence Gluck and G. Duvert and Alain E. Chelli and Yves Bresson and Udo Beckmann and Pierre Antonelli and Gerd Weigelt and No{\"e}l Ventura and Martin Vannier and J. C. Valtier and Leonardo Testi and Eric Tatulli and D. Tasso and Paolo Stefanini and P. Stee and Walter Solscheid and Dieter Schertl and Piero Salinari and Michel Sacchettini and Andrea Richichi and François Reynaud and Sylvestre Rebattu and Yves Rabbia and Thomas Preibisch and Christian Perrier and Franco Pacini and Keiichi Ohnaka and Eddy Nussbaum and David Mouillet and J. L. Monin and Pierre Mege and Ph. Mathias and Gr{\'e}goire Martinot‐Lagarde and G. A. de Mars and Alessandro Marconi and Yves Magnard and Bruno Lopez and D. Le Contel and J. M. le Contel and Stefan Kraus and D. Kamm and K. H. Hofmann and Oscar Hern{\'a}ndez Utrera and Matthias Heininger and M. Heiden and Carla S. Gil and E. Giani and Andre Glentzlin and Sandro Gennari and A. Gallardo and Didier Fraix-Burnet and Renaud Foy and Eric G. Fossat and Thierry Forveille and Debora Ferruzzi and Philippe Feautrier and M. Dugu'e and Thomas Driebe and A. Domiciano de Souza and A. Delboulb'e and Claus Connot and Jacques Colin and J. M. Clausse and Fr{\'e}d{\'e}ric Cassaing and Simone Busoni and Serge Bonhomme and Thomas Blocker and Jack Behrend and Carlo Baffa and Eric Aristidi and Brahim Arezki and Karim Agabi and Bram Acke and Matteo Accardo and Mario J. Kiekebusch and Fredrik T. Rantakyro and Markus Schoeller},
  journal={Astronomy and Astrophysics},
In this work, we present the first AMBER observations, of the Wolf-Rayet and O (WR+O) star binary system y² Velorum. The AMBER instrument was used with the telescopes UT2, UT3, and UT4 on baselines ranging from 46m to 85m. It delivered spectrally dispersed visibilities, as well as differential and closure phases, with a resolution R = 1500 in the spectral band 1.95-2.17 micron. We interpret these data in the context of a binary system with unresolved components, neglecting in a first… 

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