[en] We report the discovery of very shallow (DF/F = 3.4 10-4), periodic dips in the light curve of an active V = 11.7 G9V star observed by the CoRoT satellite, which we interpret as due to the presence of a transiting companion. We describe the 3-colour CoRoT data and complementary ground-based observations that support the planetary nature of the companion. Methods. We use CoRoT color information, good angular resolution ground-based photometric observations in- and out- of transit, adaptive optics imaging, near-infrared spectroscopy and preliminary results from Radial Velocity measurements, to test the diluted eclipsing binary scenarios. The parameters of the host star are derived from optical spectra, which were then combined with the CoRoT light curve to derive parameters of the companion. We examine carefully all conceivable cases of false positives, and all tests performed support the planetary hypothesis. Blends with separation larger than 0.40 arcsec or triple systems are almost excluded with a 8 10-4 risk left. We conclude that, as far as we have been exhaustive, we have discovered a planetary companion, named CoRoT-7b, for which we derive a period of 0.853 59 +/- 3 10-5 day and a radius of Rp = 1.68 +/- 0.09 REarth. Analysis of preliminary radial velocity data yields an upper limit of 21 MEarth for the companion mass, supporting the finding. CoRoT-7b is very likely the first Super-Earth with a measured radius.
Disciplines :
Space science, astronomy & astrophysics
Author, co-author :
Leger, A.
Rouan, D.
Schneider, J.
Barge, P.
Fridlund, M.
Samuel, B.
Ollivier, M.
Guenther, E.
Deleuil, M.
Deeg, H. J.
Auvergne, M.
Alonso, R.
Aigrain, S.
Alapini, A.
Almenara, J. M.
Baglin, A.
Barbieri, M.
Bruntt, H.
Borde, P.
Bouchy, F.
Cabrera, J.
Catala, C.
Carone, L.
Carpano, S.
Csizmadia, Szilard
Dvorak, R.
Erikson, A.
Ferraz-Mello, S.
Foing, B.
Fressin, F.
Gandolfi, D.
Gillon, Michaël ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Astrophysique et traitement de l'image
Alonso, R., Aigrain, S., Pont, F., Mazeh, T., & The CoRoT Exoplanet Science Team 2009, in IAU Symp., 253, 91
Alonso, R., Auvergne, M., Baglin, A., et al. 2008, A&A, 482, L21
Auvergne, M. 2006, in ESA SP 1306, ed. M. Fridlund, A. Baglin, J. Lochard, & L. Conroy, 283
Baglin, A., Auvergne, M., Boisnard, L., et al. 2006, in COSPAR, Plenary Meeting, 36, 36th COSPAR Scientific Assembly, 3749
Barge, P., Baglin, A., Auvergne, M., et al. 2008, A&A, 482, L17
Barnes, S. A. 2007, ApJ, 669, 1167
Bouchy, F., Mayor, M., Lovis, C., et al. 2009, A&A, 496, 527
Bouchy, F., & The Sophie Team. 2006, in Tenth Anniversary of 51 Peg-b: Status of and prospects for hot Jupiter studies, ed. L. Arnold, F. Bouchy, & C. Moutou, 319
Boulade, O., Charlot, X., Abbon, P., et al. 2003, in SPIE Conf. Ser. 4841, ed. M. Iye, & A. F. M. Moorwood, 72
Bruntt, H., De Cat, P., & Aerts, C. 2008, A&A, 478, 487
Carone, L., & Pätzold, M. 2007, Planet. Space Sci., 55, 643
Carpano, S., Cabrera, J., Alonso, R., et al. 2009, A&A, 506, 491
Carpenter, J. M. 2001, AJ, 121, 2851
Chandrasekhar, S. 1969, Ellipsoidal figures of equilibrium, ed. N. H. (Yale University Press)
Claret, A. 2000, A&A, 363, 1081
Deeg, H. J., Gillon, M., Shporer, A., et al. 2009, A&A, 506, 343
Deleuil, M., Deeg, H. J., Alonso, R., et al. 2008, A&A, 491, 889
Deleuil, M., Meunier, J. C., Moutou, C., et al. 2009, AJ, 138, 649
Drilling, J. S., & Landolt, A. U. 2000, Normal Stars (Allen's Astrophysical Quantities), 381
Elkins-Tanton, L. T., & Seager, S. 2008, ApJ, 688, 628
Frasca, A., Alcalá, J. M., Covino, E., et al. 2003, A&A, 405, 149
Murray, C. D., & Dermott, S. F. 1999, Solar system dynamics (Murray, C. D. and Dermott, S. F.)
Noyes, R. W., Hartmann, L. W., Baliunas, S. L., Duncan, D. K., & Vaughan, A. H. 1984, ApJ, 279, 763
Oscoz, A., Rebolo, R., López, R., et al. 2008, in SPIE Conf. Ser., 7014
Paresce, F. 1984, AJ, 89, 1022
Pätzold, M., & Rauer, H. 2002, ApJ, 568, L117
Pätzold, M., Carone, L., & Rauer, H. 2004, A&A, 427, 1075
Pont, F., Knutson, H., Gilliland, R. L., Moutou, C., & Charbonneau, D. 2008, MNRAS, 385, 109
Pont, F., Moutou, C., Gillon, M., et al. 2007, A&A, 465, 1069
Press, W. H., Teukolsky, S. A., Vetterling, W. T., et al. 1992, Numerical recipes in FORTRAN.The art of scientific computing, 2nd (Cambridge: University Press)
Quentin, C., Cautain, R., & Barge, P. 2006, in Astronomical Data Analysis Software and Systems XV, ed. C. Gabriel, C. Arviset, D. Ponz, & S. Enrique, ASP Conf. Ser., 351, 307
Rouan, D., Baglin, A., Barge, P., et al. 2000, in Darwin and Astronomy: the Infrared Space Interferometer, ed. B. Schürmann, ESA SP, 451, 221
Rouan, D., Baglin, A., Copet, E., et al. 1998, Earth Moon and Planets, 81, 79
Santos, N. C., Mayor, M., Naef, D., et al. 2000, A&A, 361, 265
Sozzetti, A., Torres, G., Charbonneau, D., et al. 2007, ApJ, 664, 1190
Stelzer, B., Burwitz, V., Audard, M., et al. 2002, A&A, 392, 585
Straizys, V., & Kuriliene, G. 1981, Ap&SS, 80, 353
Strassmeier, K. G., Hall, D. S., Fekel, F. C., et al. 1993, A&AS, 100, 173
Surace, C., Meunier, J.-C., Granet, Y., Deleuil, M., & Moutou, C. 2008, in Astronomical Data Analysis Software and Systems XVII, ed. R. W. Argyle, P. S. Bunclark, & J. R. Lewis, ASP Conf. Ser., 394, 373
Tokovinin, A. 2008, MNRAS, 389, 925
Valencia, D., Sasselov, D. D., & O'Connell, R. J. 2007, ApJ, 665, 1413
Vasavada, A. R., Paige, D. A., & Wood, S. E. 1999, Icarus, 141, 179
Voges, W., Aschenbach, B., Boller, T., et al. 1999, A&A, 349, 389
Wright, J. T., Marcy, G. W., Butler, R. P., et al. 2004, ApJS, 152, 261
Yoder, C. F. 1995, in Global Earth Physics: A Handbook of Physical Constants, ed. T. J. Ahrens
