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arXiv · 0803.3209

Transiting exoplanets from the CoRoT space mission III. The spectroscopic transit of CoRoT-Exo-2b with SOPHIE and HARPS

F. Bouchy·D. Queloz·M. Deleuil·B. Loeillet·A. P. Hatzes·S. Aigrain·R. Alonso·M. Auvergne·A. Baglin·P. Barge·W. Benz·P. Bordé·H. J. Deeg·R. De la Reza·R. Dvorak·A. Erikson·M. Fridlund·P. Gondoin·T. Guillot·G. Hébrard·L. Jorda·H. Lammer·A. Léger·A. Llebaria·P. Magain·M. Mayor·C. Moutou·M. Ollivier·M. Pätzold·F. Pepe·F. Pont·H. Rauer·D. Rouan·J. Schneider·A. H. M. J. Triaud·S. Udry·G. Wuchterl
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Abstract

We report on the spectroscopic transit of the massive hot-Jupiter CoRoT-Exo-2b observed with the high-precision spectrographs SOPHIE and HARPS. By modeling the radial velocity anomaly occurring during the transit due to the Rossiter-McLaughlin (RM) effect, we determine the sky-projected angle between the stellar spin and the planetary orbital axis to be close to zero lambda=7.2+-4.5 deg, and we secure the planetary nature of CoRoT-Exo-2b. We discuss the influence of the stellar activity on the RM modeling. Spectral analysis of the parent star from HARPS spectra are presented.

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F. Bouchy, D. Queloz, M. Deleuil, B. Loeillet, A. P. Hatzes, S. Aigrain, R. Alonso, M. Auvergne, A. Baglin, P. Barge, W. Benz, P. Bordé, H. J. Deeg, R. De la Reza, R. Dvorak, A. Erikson, M. Fridlund, P. Gondoin, T. Guillot, G. Hébrard, L. Jorda, H. Lammer, A. Léger, A. Llebaria, P. Magain, M. Mayor, C. Moutou, M. Ollivier, M. Pätzold, F. Pepe, F. Pont, H. Rauer, D. Rouan, J. Schneider, A. H. M. J. Triaud, S. Udry, G. Wuchterl. 2008-03-21. Transiting exoplanets from the CoRoT space mission III. The spectroscopic transit of CoRoT-Exo-2b with SOPHIE and HARPS. https://doi.org/10.1051/0004-6361:200809433

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