1:00–2:00 pm ERC 401
Emily Gilbert "The Detection and Characterization of Exoplanets Around M Dwarf Stars Using TESS"
The ongoing Transiting Exoplanet Survey Satellite (TESS) mission is an all-sky survey designed to detect planets around bright, nearby stars by providing high-cadence, precision photometry for hundreds of thousands of targets. TESS is optimized to detect planets around M dwarf stars, and my work focuses on the detection and characterization of such worlds. As the most common stellar type, with strong planet signals in both radial velocity and transit, M dwarf stars are ideal targets for exoplanet searches. But M dwarf transit searches and planet characterization are complicated by stellar activity in their light curves. Herein, I describe my research on detecting and characterizing planets orbiting M dwarf stars, particularly in the presence of spot modulation and flares. I begin by investigating the properties of the TOI-700 planets, including TOI-700 d, the first Habitable Zone, Earth-sized planet discovered with TESS. I inspect 11 Sectors of TESS observations and fit the transits of each of the 3 known planets in the system to determine their radii. Next, I study a more active star: the pre-Main Sequence M dwarf, AU Mic. AU Mic exhibits significant variability in its light curve in the form of spot modulation and flares. Both of these features complicate the transit fits for AU Mic b and c, but by fitting the activity and transits simultaneously, I am able to construct accurate transit models, and therefore derive precise planet radii and transit times. Finally, I model the optical flares of Proxima Centauri observed by TESS in order to conduct a transit search across the entire Habitable Zone of the star and show no evidence for transits of planet b or any other planets down to the size of Mars.
