EDP Sciences
The CoRoT space mission: early results
Free access
Issue
A&A
Volume 506, Number 1, October IV 2009
The CoRoT space mission: early results
Page(s) 343 - 352
Section Planets and planetary systems
DOI http://dx.doi.org/10.1051/0004-6361/200912011
Published online 15 July 2009
A&A 506, 343-352 (2009)
DOI: 10.1051/0004-6361/200912011

Ground-based photometry of space-based transit detections: photometric follow-up of the CoRoT  mission

H. J. Deeg1, M. Gillon2, 3, A. Shporer4, D. Rouan5, B. Stecklum6, S. Aigrain7, A. Alapini7, J. M. Almenara1, R. Alonso8, M. Barbieri8, F. Bouchy9, J. Eislöffel6, A. Erikson10, M. Fridlund11, P. Eigmüller6, G. Handler12, A. Hatzes6, P. Kabath10, M. Lendl12, T. Mazeh4, C. Moutou8, D. Queloz2, H. Rauer10, 13, M. Rabus1, B. Tingley1, and R. Titz10

1  Instituto de Astrofísica de Canarias, C. via Lactea S/N, 38205 La Laguna, Tenerife, Spain
    e-mail: hdeeg@iac.es
2  Observatoire de Genève, Université de Genève, 51 chemin des Maillettes, 1290 Sauverny, Switzerland
3  Institut d'Astrophysique et de Géophysique, Université de Liège, 4000 Liège, Belgium
4  School of Physics and Astronomy, Tel Aviv University, Tel Aviv 69978, Israel
5  LESIA, Observatoire de Paris-Meudon, 5 place Jules Janssen, 92195 Meudon, France
6  Thüringer Landessternwarte, Sternwarte 5, Tautenburg 5, 07778 Tautenburg, Germany
7  School of Physics, University of Exeter, Stocker Road, Exeter EX4 4QL, UK
8  Laboratoire d'Astrophysique de Marseille, 38, rue Frédéric Joliot-Curie, 13388 Marseille Cedex 13, France
9  Institut d'Astrophysique de Paris, Université Pierre & Marie Curie, 98bis Bd Arago, 75014 Paris, France
10  Institute of Planetary Research, DLR, Rutherfordstr. 2, 12489 Berlin, Germany
11  Research and Scientific Support Department, ESTEC/ESA, 2200 Noordwijk, The Netherlands
12  Institute of Astronomy, University of Vienna, Türkenschanzstr. 17, 1180 Vienna, Austria
13  Center for Astronomy and Astrophysics, TU Berlin, Hardenbergstr. 36, 10623 Berlin, Germany

Received 9 March 2009 / Accepted 9 July 2009

Abstract
The motivation, techniques and performance of the ground-based photometric follow-up of transit detections by the CoRoT space mission are presented. Its principal raison d'être arises from the much higher spatial resolution of common ground-based telescopes in comparison to CoRoT's cameras. This allows the identification of many transit candidates as arising from eclipsing binaries that are contaminating CoRoT's lightcurves, even in low-amplitude transit events that cannot be detected with ground-based obervations. For the ground observations, “on” – “off” photometry is now largely employed, in which only a short timeseries during a transit and a section outside a transit is observed and compared photometrically. CoRoTplanet candidates' transits are being observed by a dedicated team with access to telescopes with sizes ranging from 0.2 to 2 m. As an example, the process that led to the rejection of contaminating eclipsing binaries near the host star of the Super-Earth planet CoRoT-7b is shown. Experiences and techniques from this work may also be useful for other transit-detection experiments, when the discovery instrument obtains data with a relatively low angular resolution.


Key words: methods: observational -- techniques: photometric -- stars: planetary systems -- stars: binaries: eclipsing



© ESO 2009