Séminaire Exoplanètes / |
| « Numerical modeling of exomoons signals » |
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Marie Azevedo |
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In May 2022, more than 4000 exoplanets are confirmed, with masses ranging from 0.01 M?? to 200 M??. Even with such a diversity of planets, no exomoons are confirmed yet. Two candidates, Kepler 1625B - I (Teachey and Kipping [2018]) and Kepler 1708-I (Kipping et al. [2022]), have, however, been proposed. The two studies relies on transit light curves special features that could be compatible with the presence of a in-transit Neptune-sized exomoon. The quality of fit between photodynamical models and observations are overall great for both studies but the authors outline in both cases that conclusions can not be drawn, as only a few number of transit are available.
The transit timing variations (TTV), first introduced by Sartoretti and Schneider [1999] could be an indi- cator of exomoons presence. Transit timing variations have been observed several times in exosystems. In particular, Teachey and Kipping [2018] report a TTV of 20 mins associated to Kepler 1625B. Even if analytical (see by example Kipping [2011]) and observational (Szabó et al. [2022]) works have been made, no numerical models of TTV evolution are available. Hence, this study propose to produce simulated TTV observa- tions. A transfert function have been developed based on the analytical work of Kipping [2011] and designed to work with the numerical integrator NOE (Numerical Orbits and Ephemerides, Lainey et al. [2004]).It produces numerical TTV’s for a given exosystem. Two numerical simulations have been run. A simplified Earth-Moon scenario and a simulation of the Kepler 1625B system with a M?? range mass. In both cases, analytical values in the sense of Kipping [2011] are satisfying. Further steps of the work includes a parametric study and the numerical modeling of associated lightcurves. The use of NOE together with the transfert function will allow to perform simulations with multiple non spherical bodys and hence allow to study moon contributions. |
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jeudi 30 juin 2022 - 14:00 Salle des séminaires Évry Schatzman Institut d'Astrophysique de Paris |
| Page web du séminaire / Seminar's webpage |