My work as a post-doctoral researcher, both at Goettingen University and at Aarhus University, has been mainly focused into two areas: the characterization of the atmospheres of exoplanets, and the determination of their dynamical masses through transit timing variations. I have dedicated my first years as postdoctoral researcher at SAC and my posterior years as assistant professor to deepen my knowledge about exo-atmospheric characterization. While my ultimate, personal goal is to find biomarkers in the atmospheres of alien worlds that resembles our Earth, due to technological limitations hot Jupiters are most frequently targeted. Even though it is extremely unlikely that life can develop on such extreme worlds they are still worth to study, as they can serve to contrast current models of atmospheres with observational data of good quality. Through low resolution transmission spectroscopy I have investigated macro-features in a wide wavelength range, such as the presence of clouds or hazes. Here, I have intensively contributed to the field, finding for instance the first indication of aluminium oxide in an exoplanet atmosphere, and one of the first attempts at carrying out comparative studies between two exoplanets. I have also developed a novel model for transmission spectroscopy. Owing to the extremely high quality of the data, I could construct and test a detailed model including variations in the intensity of the light from the star. This demonstrated that the position of the planet over the stellar disk impacts the stellar energy budget and thereby the interaction with the exo-atmosphere. I found that the planetary spectrum moved significantly relative to the stellar spectrum, modulating the absorption signal. In addition, I have found evidences for hydrogen Roche Lobe overflow (paper submitted), and I have determined the temperature-versus-altitude profile obtained from fitting the exo-atmospheric Na D2 absorption line in the core, wings and continuum.
Orbital dynamics, and particularly orbital perturbations, have also occupied a significant amount of my research time. During my 6-month stay at the Institute for Astrophysics Goettingen, I built and since then lead the Kepler Object of Interest Network (KOINet) an international network of researchers with access to ground-based telescopes organized by me to carry out the photometric follow-up of Kepler planets showing Transit Timing Variations that required more data than Kepler's to properly determine their masses. After introducing the network and our milestones, we predicted transits of Kepler-9c to disappear in 2050, and we found a non-transiting exoplanet in the Kepler-82 system. Other TTV efforst include the study of Neptune-sized exoplanets.
I have dedicated my PhD to the detailed study of transiting hot Jupiters. I have investigated several aspects of these extreme worlds, including not only the determination of the properties of the planets, but those of the host stars as well. During my three years of
PhD study I gained experience in several areas, such as transit fitting techniques, orbital dynamics, asteroseismology, stellar polarization, stellar activity, the use and development of modern statistical tools, and reduction and analysis techniques for photometric, spectroscopic, and polarimetric data. I quickly learned how to become an independent researcher, developing my own collaborations. During my PhD I focused my research mainly in the detailed characterization of two exoplanets, Qatar-1b and WASP-33b. For Qatar-1b I carried out a photometric follow-up of the system during transits. Over two years I collected up to 50 transit light curves that I used to investigate the feasibility of transit timing variations. For WASP-33b, I carried out a photometric follow-up of the system for two and a half years. I collected around 650 hours of in-and-out of transit photometry, that I used to characterize the pulsation spectrum of the host star and, with it, the transit parameters of WASP-33b free of pulsations.
As part of a collaborative effort between the National University of Buenos Aires and the National University of La Plata, I assembled a 0.4 meter telescope, for the express purpose of carrying out observations of exoplanet primary transits. The telescope, now available to the Argentinian astronomical community, is located at El Leoncito, Argentina's largest observatory. The telescope, and my work connected to it, were pioneer efforts to carry out exoplanet research in Argentina.