Photometry and spectroscopy of transiting extrasolar planets.

Abstract

The search for exoplanets is often most captivating when concerning the discovery of Earth-like planets that could possibly sustain life, according to our current understanding of the environmental requirements. However, current estimates suggest that habitable planets are a minority. In order to fully understand the trends, structure and formation of planetary systems, more information about exoplanets and their systems is needed. No exoplanets offer up as much information as transiting exoplanets. The data collected for this thesis was as part of a follow-up effort for the KELT-South (Kilo-degree Extremely Little Telescope in the southern hemisphere) project, which uses the wide-field surveying photometric telescope to search for transiting exoplanets, usually of the hot Jupiter variety. Follow-up lightcurves have been produced for many different candidate stars. Of those presented four suggest spurious survey data, and five suggest false-positives due to blended or grazing eclipsing binaries; these have been ruled out as exoplanet candidates. Eight of the lightcurves produced still appear to be likely transiting exoplanets, but require further photometry or high precision spectroscopy in order to be confirmed. Radial velocity (RV) follow-up was performed on two KELT-South transiting exoplanet candidates (HD 113204 and HD 9468). More data is needed for both targets though an upper projected mass limit of 0:24MX was placed on the companion of HD 9468. A meaningful estimate for the projected mass of the planetary companion of HD 113204 could not be made as there was too little data