WASP-14 b: Transit Timing analysis of 19 light curves

TL;DR

This study presents new transit observations of exoplanet WASP-14 b, refining its orbital period and confirming the absence of transit timing variations over a seven-year span.

Contribution

It provides the first extensive photometric follow-up of WASP-14 b, improving the orbital parameters and demonstrating the system's stability without TTV signals.

Findings

Refined orbital period with 10x precision

No evidence of transit timing variations

Confirmed system parameters consistent with discovery data

Abstract

Although WASP-14 b is one of the most massive and densest exoplanets on a tight and eccentric orbit, it has never been a target of photometric follow-up monitoring or dedicated observing campaigns. We report on new photometric transit observations of WASP-14 b obtained within the framework of "Transit Timing Variations @ Young Exoplanet Transit Initiative" (TTV@YETI). We collected 19 light-curves of 13 individual transit events using six telescopes located in five observatories distributed in Europe and Asia. From light curve modelling, we determined the planetary, stellar, and geometrical properties of the system and found them in agreement with the values from the discovery paper. A test of the robustness of the transit times revealed that in case of a non-reproducible transit shape the uncertainties may be underestimated even with a wavelet-based error estimation methods. For the timing analysis we included two publicly available transit times from 2007 and 2009. The long observation period of seven years (2007-2013) allowed us to refine the transit ephemeris. We derived an orbital period 1.2 s longer and 10 times more precise than the one given in the discovery paper. We found no significant periodic signal in the timing-residuals and, hence, no evidence for TTV in the system.