K2-19, The first K2 muti-planetary system showing TTVs

BARROS, S. C. C.; ALMENARA, J. M.; DEMANGEON, O.; TSANTAKI, M.; SANTERNE, A.; ARMSTRONG, D. J.; BARRADO, D.; BROWN, D.; DELEUIL, M.; LILLO-BOX, J.; OSBORN, H.; POLLACCO, D.; ABE, L.; ANDRE, P.; BENDJOYA, P.; BOISSE, I.; BONOMO, A. S.; BOUCHY, F.; BRUNO, G.; CERDA, J. REY; COURCOL, B.; DÍAZ, R. F.; HÉBRARD, G.; KIRK, J.; LACHURIÉ, J. C.; LAM, K. W. F.; MARTINEZ, P.; MCCORMAC, J.; MOUTOU, C.; RAJPUROHIT, A.; RIVET, J.-P.; SPAKE, J.; SUAREZ, O.; TOUBLANC, D.; WALKER, S. R.

Honolulu

Congreso; IAU XXIX General Assembly; 2015

In traditional transit timing variations (TTVs) analysis ofmulti-planetary systems, the individual TTVs are first derived fromtransit fitting and later modelled using n-body dynamic simulations toconstrain planetary masses. We show that fitting simultaneously thetransit light curves with the system dynamics (photo-dynamical model)increases the precision of the TTV measurements and helps constrain thesystem architecture. We exemplify the advantages of applying thisphoto-dynamical model to a multi-planetary system found in K2 data veryclose to 3:2 mean motion resonance, K2-19. In this case the period ofthe larger TTV variations (libration period) is much longer (>1.5years) than the duration of the K2 observations (80 days). However, ourmethod allows to detect the short period TTVs produced by the orbitalconjunctions between the planets that in turn permits to uniquelycharacterise the system. Therefore, our method can be used to constrainthe masses of near-resonant systems even when the full libration curveis not observed.