Transit analysis of the CoRoT-5, CoRoT-8, CoRoT-12, CoRoT-18, CoRoT-20, and CoRoT-27 systems with combined ground- And space-based photometry
We have initiated a dedicated project to follow-up with ground-based photometry the transiting planets discovered by CoRoT in order to refine the orbital elements, constrain their physical parameters, and search for additional bodies in the system. From 2012 September to 2016 December we carried out 16 transit observations of six CoRoT planets (CoRoT-5 b, CoRoT-8 b, CoRoT-12 b, CoRoT-18 b, CoRoT-20 b, and CoRoT-27 b) at three observatories located in Germany and Spain. These observations took place between 5 and 9 yr after the planet's discovery, which has allowed us to place stringent constraints on the planetary ephemeris. In five cases we obtained light curves with a deviation of the mid-transit time of up to ∼115 min from the predictions. We refined the ephemeris in all these cases and reduced the uncertainties of the orbital periods by factors between 1.2 and 33. In most cases our determined physical properties for individual systems are in agreement with values reported in previous studies. In one case, CoRoT-27 b, we could not detect any transit event in the predicted transit window.© 2018 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. ; SR acknowledge support from the People Programme (Marie Curie Actions) of the European Union's Seventh Framework Programme (FP7/2007-2013) under Research Executive Agency (REA) grant agreement no. [609305]. MF acknowledges financial support from grants AYA2014-54348-C3-1-R, AYA2011-30147-C03-01, and AYA2016-79425-C3-3-P of the Spanish Ministry of Economy and Competivity (MINECO), co-funded with EU FEDER funds. CM acknowledges support from the German Science Foundation (DFG) through grant SCHR665/7-1. The present study was made possible thanks to observations obtained with CoRoT, a space project operated by the French Space Agency, CNES, with partic-ipation of the Science Program of ESA, ESTEC/RSSD, Austria, Belgium, Brazil, Germany, and Spain. ; Peer Reviewed