Master's Thesis Defense by Francisco Ardévol Martı́nez
Supervisor: Heidi Korhonen
Co-supervisor: Anja Andersen
External examiner: Hans Kjeldsen, Aarhus University
Title: TYC 2627-638-1: Two possible planets in a triple star system
Abstract: TYC-2627-638-1 is a wide binary composed of two solar like stars. Analysis of spectral line profiles found changing features in the main star that could be best explained by it being a spectroscopic binary. Radial velocity measurements showed periodic variations consistent with a possible substellar body also orbiting the main star with a period of 1.59 days (Oláh et al. 2010). The aim of this work is to confirm the existence of the possible exoplanet and confirm the binary nature of the main star. Analysis of UVES spectra of TYC 2627-638-1A showed the data to be insufficient to confirm the hot Jupiter around it, but could be used to prove the existence of the red stellar companion (TYC2627-638-1C). The red companion has a period of 728.88 days with an orbital radius of 1.7 AU. Its mass was found to be Msin3i = 0.42 ± 0.09 Msolar ?. Radial velocity measurements of TYC 2627-638-1B seem to indicate the presence of a hot Jupiter of M sin i ∼ 4 M Jup on a 12.5 days orbit around it, although more observations are needed to confidently discard stellar activity or other mechanisms as the source of these variations.