Keele Research Repository

The WASP project has discovered many transiting gas giant exoplanets. Some of these exoplanet systems have been observed by the K2 space-based telescope. The much higher photometric precision, shorter cadence and extended continuous follow-up observations provided by the K2 mission enabled the most detailed photometric characterization yet of the WASP and other planetary systems presented in this thesis, which contributes to our understanding of how planets form and evolve.
I analysed the majority of transiting exoplanet systems observed by the K2 in the 1-min short-cadence mode within the first 14 regular observing campaigns. I present here the analysis and results for a total of 10 planetary systems observed in the short-cadence mode. I detected starspot occultation events in two aligned and one misaligned planetary system and proved that detecting starspot occultation events is possible in the K2 data. I also detected optical phase-curve modulations in two systems, rotational modulations in four and γ Doradus pulsations in one planetary system. I refined the system parameters for all short-cadence targets and used non-detections to provide tight upper limits. In addition, I discovered a hot Jupiter using the long-cadence K2 data and refined the ephemeris with the WASP data of another K2-discovered planet.