Abstracts Astronomy & Space Science

Exoplanet atmospheres at high spectral resolution in the near-infrared

by Rebecca K. Webb

The study of exoplanets planets as a field is only three decades old, however, it is now one of the biggest areas of research in astrophysics. This is because fundamentally all of the exoplanet research attempts to answer one of the biggest questions in humanity, are we alone in the Universe? One of the only ways for scientists to fully answer that question lies in the understanding of the gaseous envelope that surrounds these planets, known as the atmosphere. These atmospheres hold key information about their formation and migration histories through their primordial disks. The key to unlocking that information is through spectroscopic observations which can be used to determine the chemistry and physical processes within these atmospheres. I present two separate analyses of high resolution observations of two nontransiting hot Jupiters, HD179949 b (chapter 3) and τ Bo¨otis b (chapter 4), in the near-infrared. For HD179949 b, I present the detection of water vapour in the Lband using the CRIRES instrument. For τ Bo¨otis b, I also present the detection of water vapour in the atmosphere using the CARMENES instrument. The latter detection is in disagreement with recent observations taken with the SPIRou instrument which is discussed in chapter 4.8. In chapter 5, I present a simulated analysis of high resolution spectroscopic observations of an Earth-like planet from the ELT 39m telescope around M-dwarf stars. This study aimed to simulate the typical data analysis techniques on a time series data-set currently used on high resolution spectroscopic data typically used for faster orbiting planets. This analysis used principal component analysis (PCA) on these simulations to remove time varying flux variations. It was found that PCA removed most, if not all, of the planets signal due to the fact that a habitable planet, even around later type M-dwarfs move too slowly for this methodology to be feasible.