Letter to the Editor
I. CoRoT-Exo-1b: a low-density short-period planet around a G0V star
Laboratoire d'Astrophysique de Marseille, UMR6110, CNRS/Université de Provence, BP 8, 13376 Marseille Cedex 12, France e-mail: firstname.lastname@example.org
2 LESIA, Observatoire de Paris-Meudon, 5 place Jules Janssen, 92195 Meudon, France
3 Institute of Planetary Research, DLR, Rutherfordstr. 2, 12489 Berlin, Germany
4 Center for Astronomy and Astrophysics, TU Berlin, Hardenbergstr. 36, 10623 Berlin, Germany
5 Institut d'Astrophysique Spatiale, Université Paris XI, 91405 Orsay, France
6 LUTH, Observatoire de Paris-Meudon, 5 place Jules Janssen, 92195 Meudon, France
7 Observatoire de Genève, Université de Genève, 51 chemin des Maillettes, 1290 Sauverny, Switzerland
8 School of Physics, University of Exeter, Stocker Road, Exeter EX4 4QL, UK
9 Instituto de Astrofísica de Canarias, 38205 La Laguna, Tenerife, Spain
10 Institut d'Astrophysique de Paris, Université Pierre & Marie Curie, 98bis Bd Arago, 75014 Paris, France
11 Observatório Nacional, Rio de Janeiro, RJ, Brazil
12 University of Vienna, Institute of Astronomy, Türkenschanzstr. 17, 1180 Vienna, Austria
13 Research and Scientific Support Department, ESTEC/ESA, 2200 Noordwijk, The Netherlands
14 Observatoire de la Côte d'Azur, Laboratoire Cassiopée, BP 4229, 06304 Nice Cedex 4, France
15 Thüringer Landessternwarte, Sternwarte 5, Tautenburg 5, 07778 Tautenburg, Germany
16 Space Research Institute, Austrian Academy of Science, Schmiedlstr. 6, 8042 Graz, Austria
17 University of Liège, Allée du 6 août 17, Sart Tilman, Liège 1, Belgium
18 School of Physics and Astronomy, Tel Aviv University, Tel Aviv 69978, Israel
19 Rheinisches Institut für Umweltforschung an der Universität zu Köln, Aachener Strasse 209, 50931, Germany
Accepted: 11 March 2008
Context. The pioneer space mission for photometric planet searches, CoRoT, steadily monitors about 12 000 stars in each of its fields of view. Transit candidates can be detected early in the processing of the data and before the end of a run of observation.
Aims. We report the detection of the first planet discovered by CoRoT and characterizing it with the help of follow-up observations.
Methods. Raw data were filtered from outliers and residuals at the orbital period of the satellite. The orbital parameters and the radius of the planet were estimated by best fitting the phase folded light curve with 34 successive transits. Doppler measurements with the SOPHIE spectrograph permitted us to secure the detection against binaries and to estimate the mass of the planet.
Results. The accuracy of the data is very high with a dispersion in the 2.17 min binned phase-folded light curve that does not exceed ~3.10-4 in flux unit. The planet orbits a mildly metal-poor G0V star of magnitude in 1.5 days. The estimated mass and radius of the star are 0.95±0.15 and 1.11±0.05 . We find the planet has a radius of 1.49±0.08 RJup, a mass of 1.03±0.12 MJup, and a particularly low mean density of 0.38±0.05 g cm-3.
Key words: planetary systems / techniques: photometry / techniques: radial velocity
The CoRoT space mission, launched on Dec. 27th, 2006, was developed and is operated by the CNES, with participation of the Science Program of ESA, ESTEC/RSSD, Austria, Belgium, Brazil, Germany and Spain. Based in part on observations with the SOPHIE spectrograph at Obs. de Haute Provence, France.
© ESO, 2008