Stellar and planetary characterization of two Kepler multi-planet systems from high-quality Gemini/GRACES spectra

E. JOFRÉ, R. PETRUCCI, E. MARTIOLI, I. RAMÍREZ, Y. GOMEZ MAQUEO CHEW, C. SAFFE, A. BUCCINO, L. GARCÍA, R.F. DÍAZ, M. GOMEZ

Pasadena, CA

Workshop; 2018 Sagan Exoplanet Summer Workshop - Did I Really Just Find an Exoplanet?; 2018

Jet propulsion Laboratory (JPL) - California Institute of Technology (Caltech)

Our understanding of exoplanets structure, composition, formation, and evolution is strongly linked to our knowledge of a series of fundamental parameters of their host stars. On the one hand, stellar composition and mass have a major influence on the formation and evolution of planetary systems (e.g., Fischer and Valenti 2005 ApJ 622:1102, Mayor et al. 2014 Nature 513:328, Adibekyan et al 2013 A&A 560:A51). On the other hand, models of planetary structure and composition rely on accurate estimations of their masses and radii, which for transiting planets, depend critically on the mass and radius of the parent star. These stellar properties, in turn, depend on the atmospheric parameters of the star, which can be derived from high-quality spectra. However, this kind of spectra is not commonly available for faint planet host stars such as those in the Kepler field. In this context, based on high-quality spectra, we present the first detailed chemical abundance analysis of two Kepler Evolved Objects (KEO-364 and KEO-123, in our catalog) that host multiple planets. In addition, from new precise atmospheric parameters, we derive refined stellar and planetary physical properties.