Title: Systematic Uncertainties in Transiting Exoplanets and Their Host Stars
Speaker: Alison Duck (OSU)
Abstract:
Transiting systems offer a unique opportunity to measure precise masses and radii of planets and their host stars However, relative photometry and radial velocity measurements alone only constrain the host star density, leaving a one-parameter mass-radius degeneracy. I assess the magnitude of systematic errors in the derived system parameters relative to their statistical precision
due to different methods of breaking this degeneracy. I model extant data for the typical hot Jupiter system KELT-15 using EXOFASTv2, considering four methods of breaking the stellar mass-radius degeneracy.
Similar techniques can be applied in binary star properties to precisely characterize, M-dwarfs some of the most common yet faintest planet hosts. I evaluate the systematic errors for several systems of M-dwarfs transiting FGK host stars. I determine that the model uncertainty in the primary star is of similar magnitude to the statistical uncertainty in the model fits of the secondary M-dwarf.
Finally, I present 9 transiting systems with secondary eclipses observable from TESS, 8 containing hot Jupiters and 1 hosting a brown dwarf. I present new TESS secondary eclipse observations for the first time for 3 of these systems. Leveraging our sample of transiting systems, we place constraints on the average population bond albedo and heat recirculation efficiency to recover trends in hot Jupiters using only the TESS band-pass. Quantifying these systematic uncertainties and the precise characterization of exoplanet systems will unveil subtle demographic trends which provide insight into planet formation mechanisms and allow for the detailed characterization needed to understand planet composition and habitability.
