Kepler Object of Interest Network â: II. Photodynamical modelling of Kepler-9 over 8 years of transit observations
Por:
Freudenthal, J., von Essen, C., Dreizler, S., Wedemeyer, S., Agol, E., Morris, B. M., Becker, A. C., Mallonn, M., Hoyer, S., Ofir, A., Tal-Or, L., Deeg, H. J., Herrero, E., Ribas, I, Khalafinejad, S., Hernandez, J., Rodriguez S, M. M.
Publicada:
11 oct 2018
Resumen:
Context. The Kepler Object of Interest Network (KOINet) is a multi-site network of telescopes around the globe organised to follow up transiting planet-candidate Kepler objects of interest (KOIs) with large transit timing variations (TTVs). Its main goal is to complete their TTV curves, as the Kepler telescope no longer observes the original Kepler field. Aims. Combining Kepler and new ground-based transit data we improve the modelling of these systems. To this end, we have developed a photodynamical model, and we demonstrate its performance using the Kepler-9 system as an example. Methods. Our comprehensive analysis combines the numerical integration of the system's dynamics over the time span of the observations along with the transit light curve model. This provides a coherent description of all observations simultaneously. This model is coupled with a Markov chain Monte Carlo algorithm, allowing for the exploration of the model parameter space. Results. Applied to the Kepler-9 long cadence data, short cadence data, and 13 new transit observations collected by KOINet between the years 2014 and 2017, our modelling provides well constrained predictions for the next transits and the system's parameters. We have determined the densities of the planets Kepler-9b and 9c to the very precise values of ?b = 0.439 ± 0.023 g cm-3 and ?c = 0.322 ± 0.017 g cm-3. Our analysis reveals that Kepler-9c will stop transiting in about 30 yr due to strong dynamical interactions between Kepler-9b and 9c, near 2:1 resonance, leading to a periodic change in inclination. Conclusions. Over the next 30 years, the inclination of Kepler-9c (-9b) will decrease (increase) slowly. This should be measurable by a substantial decrease (increase) in the transit duration, in as soon as a few years' time. Observations that contradict this prediction might indicate the presence of additional objects in this system. If this prediction turns out to be accurate, this behaviour opens up a unique chance to scan the different latitudes of a star: High latitudes with planet c and low latitudes with planet b. © 2018 ESO.
Filiaciones:
Freudenthal, J.:
Georg August Univ Gottingen, Inst Astrophys, Friedrich Hund Pl 1, D-37077 Gottingen, Germany
von Essen, C.:
Georg August Univ Gottingen, Inst Astrophys, Friedrich Hund Pl 1, D-37077 Gottingen, Germany
Aarhus Univ, Stellar Astrophys Ctr, Ny Munkegade 120, DK-8000 Aarhus, Denmark
Dreizler, S.:
Georg August Univ Gottingen, Inst Astrophys, Friedrich Hund Pl 1, D-37077 Gottingen, Germany
Wedemeyer, S.:
Univ Oslo, Rosseland Ctr Solar Phys, POB 1029 Blindern, N-0315 Oslo, Norway
Univ Oslo, Inst Theoret Astrophys, POB 1029 Blindern, N-0315 Oslo, Norway
Agol, E.:
Univ Washington, Astron Dept, Seattle, WA 98195 USA
Inst Astrophys Paris, 98 Bis Blvd Arago, F-75014 Paris, France
Univ Washington, Virtual Planetary Lab, Seattle, WA 98195 USA
Morris, B. M.:
Univ Washington, Astron Dept, Seattle, WA 98195 USA
Becker, A. C.:
Univ Washington, Astron Dept, Seattle, WA 98195 USA
Mallonn, M.:
Leibniz Inst Astrophys Potsdam, Sternwarte 16, D-14482 Potsdam, Germany
Hoyer, S.:
Inst Astrofis Canarias, C Via Lactea S-N, Tenerife 38205, Spain
Univ La Laguna, Dept Astrofis, Tenerife 38206, Spain
Aix Marseille Univ, Lab Astrophys Marseille, CNRS, Marseille, France
Ofir, A.:
Georg August Univ Gottingen, Inst Astrophys, Friedrich Hund Pl 1, D-37077 Gottingen, Germany
Weizmann Inst Sci, Dept Earth & Planetary Sci, IL-76100 Rehovot, Israel
Tal-Or, L.:
Georg August Univ Gottingen, Inst Astrophys, Friedrich Hund Pl 1, D-37077 Gottingen, Germany
Tel Aviv Univ, Raymond & Beverly Sackler Fac Exact Sci, Sch Geosci, IL-6997801 Tel Aviv, Israel
Deeg, H. J.:
Inst Astrofis Canarias, C Via Lactea S-N, Tenerife 38205, Spain
Univ La Laguna, Dept Astrofis, Tenerife 38206, Spain
Herrero, E.:
Inst Cincies Espai IEEC CSIC, C Can Magrans S-N,Campus UAB, Bellaterra 08193, Spain
IEEC, C Gran Capita 204,Edif Nexus, Barcelona 08034, Spain
Ribas, I:
Inst Cincies Espai IEEC CSIC, C Can Magrans S-N,Campus UAB, Bellaterra 08193, Spain
IEEC, C Gran Capita 204,Edif Nexus, Barcelona 08034, Spain
Khalafinejad, S.:
Hamburg Univ, Hamburg Observ, Gojenbergsweg 112, D-21029 Hamburg, Germany
Max Planck Inst Astron, Konigstuhl 17, D-69117 Heidelberg, Germany
Hernandez, J.:
UNAM, Inst Astron, Campus Ensenada,Carretera Tijuana Ensenada Km 103, Ensenada 22860, Baja California, Mexico
Rodriguez S, M. M.:
UNAM, Inst Astron, Campus Ensenada,Carretera Tijuana Ensenada Km 103, Ensenada 22860, Baja California, Mexico
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