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Register a new userTraMoS IV: Discarding the Quick Orbital Decay Hypothesis for OGLE-TR-113b
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In the context of the TraMoS project we present nine new transit observations of the exoplanet OGLE-TR-113b observed with the Gemini South, Magellan Baade, Danish-1.54m and SOAR telescopes. We perform a homogeneous analysis of these new transits together with ten literature transits to probe into the potential detection of an orbital decay for this planet reported by citet{adams2010}. Our new observations extend the transit monitoring baseline for this system by 6 years, to a total of more than 13 years. With our timing analysis we obtained a $dot{P}=-1.0 pm 6.0$ ms~yr$^{-1}$, which rejects previous hints of a larger orbital decay for OGLE-TR-113b. With our updated value of $dot{P}$ we can discard tidal quality factors of $Q_{star} < 10^{5}$ for its host star. Additionally, we calculate a 1$sigma$ dispersion of the Transit Timing Variations (TTVs) of 42 seconds over the 13 years baseline, which discards additional planets in the system more massive than $0.5-3.0~M_{oplus}$ in 1:2, 5:3, 2:1 and 3:1 Mean Motion Resonances with OGLE-TR-113b. Finally, with the joint analysis of the 19 light curves we update transit parameters, such as the relative semi-major axis $a / R_s = 6.44^{+0.04}_{-0.05}$, the planet-to-star radius ratio $R_p / R_s =0.14436^{+0.00096}_{-0.00088}$, and constrains its orbital inclination to $i =89.27^{+0.51}_{-0.68}$~degrees.
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We present high precision K-band photometry of the transit and secondary eclipse of extrasolar planet OGLE-TR-113, using the SOFI near-infrared instrument on ESOs NTT. Data were taken in 5 second exposures over two periods of 3-4 hours, using random jitter position offsets. In this way, a relative photometric precision of ~1% per frame was achieved, avoiding systematic effects that seem to become dominant at precisions exceeding this level, and resulting in an overall accuracy of 0.1% per ~10 minutes. The observations of the transit show a flat bottom light-curve indicative of a significantly lower stellar limb-darkening at near-infrared than at optical wavelengths. The observations of the secondary eclipse result in a 3 sigma detection of emission from the exoplanet at 0.17+-0.05%. However, residual systematic errors make this detection rather tentative.
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