The goal of this project is to advance observational techniques of extrasolar planet atmospheres using large ground-based telescopes. These advancements will allow us to improve our knowledge of the chemical compositions of exoplanetary atmospheres,as well as their atmospheric circulation and thermal inversion layers. In this work I focus on the study of the hot-Jupiter WASP-18b via transmission spectroscopy. I analysed spectra of WASP-18b collected during three transit epochs with the multi-object IMACS spectrograph at the Las Campanas Observatory in Chile. My results show that it is possible to obtain transmission spectra of exoplanets with this instrument with a resolution of 6.7˚A under 1 arcsec of seeing and an average precision of 3.06% per bin, per transit. This precision is not enough to detect the atmosphere of WASP-18b, because of this planet’s very high mass and therefore small atmospheric scale height. However, with the precision I obtain it will be possible to measure atmospheric features in less massive, Jupiter-sized exoplanets. This work is part of ACCESS (the Arizona CfA-Catolica Exoplanet Spectroscopy Survey), which is a project to create the first comprehensive database of optical exoplanet spectra, using ground-based facilities.
|Type||Masters Thesis (University of Southampton)|
|Publication status||Published - 01 May 2015|