Photometric follow-up of the transiting planetary system TrES-3: Transittiming variation and long-term stability of the system

Abstract

We present new observations of the transiting system TrES-3 obtained from 2009 to 2011 at several observatories. The orbital parameters of the system were redetermined and a new linear ephemeris was calculated. The best quality light curve was used for light-curve analysis, and other data sets were used to determine mid-transit times (Tc) and study transit time variation (TTV). For planet parameter determination we used two independent codes and finally, we concluded that our parameters are in agreement with previous studies. Based on our observations, we determined 14 mid-transit times. Together with published TC, we found that the timing residuals showed no significant deviation from the linear ephemeris. We concluded that a periodic TTV signal with an amplitude greater than 1 min over a 4 yr time span seems to be unlikely. Our analysis of an upper mass limit allows us to exclude an additional Earth-mass planet close to inner 3:1, 2:1 and 5:3 and outer 3:5, 1:2 and 1:3 meanmotion resonances. Using the long-term integration and applying the method of maximum eccentricity, the region from 0.015 au to 0.05 au was found unstable and the region beyond the 0.05 au was found to have a chaotic behaviour and its depletion increases with increasing values of the initial eccentricity as well as inclination.