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. Gillon^{2, 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. Rauer^{10, 13}, M. Rabus¹, B. Tingley¹, and R. Titz<sup>10

1</sup>  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

What is OpenURL?