학술논문
The Transiting System GJ1214: High-Precision Defocused Transit Observations and a Search for Evidence of Transit Timing Variation
Document Type
Working Paper
Author
Harpsøe, K. B. W.; Hardis, S.; Hinse, T. C.; Jørgensen, U. G.; Mancini, L.; Southworth, J.; Alsubai, K. A.; Bozza, V.; Browne, P.; Burgdorf, M. J.; Novati, S. Calchi; Dodds, P.; Dominik, M.; Fang, X. -S.; Finet, F.; Gerner, T.; Gu, S. -H.; Hundertmark, M.; Kains, N.; Kerins, E.; Kjeldsen, H.; Liebig, C.; Lund, M. N.; Lundkvist, M.; Mathiasen, M.; Nesvorný, D.; Nikolov, N.; Penny, M. T.; Proft, S.; Rahvar, S.; Ricci, D.; Sahu, K. C.; Scarpetta, G.; Schäfer, S.; Schönebeck, F.; Snodgrass, C.; Skottfelt, J.; Surdej, J.; Tregloan-Reed, J.; Wertz, O.
Source
Subject
Language
Abstract
Aims: We present 11 high-precision photometric transit observations of the transiting super-Earth planet GJ1214b. Combining these data with observations from other authors, we investigate the ephemeris for possible signs of transit timing variations (TTVs) using a Bayesian approach. Methods: The observations were obtained using telescope-defocusing techniques, and achieve a high precision with random errors in the photometry as low as 1mmag per point. To investigate the possibility of TTVs in the light curve, we calculate the overall probability of a TTV signal using Bayesian methods. Results: The observations are used to determine the photometric parameters and the physical properties of the GJ1214 system. Our results are in good agreement with published values. Individual times of mid-transit are measured with uncertainties as low as 10s, allowing us to reduce the uncertainty in the orbital period by a factor of two. Conclusions: A Bayesian analysis reveals that it is highly improbable that the observed transit times is explained by TTV, when compared with the simpler alternative of a linear ephemeris.
Comment: Submitted to A&A
Comment: Submitted to A&A