CFHT UM2019 - Presentation Details

Abstract Details

Title: Simulations of SPIRou radial velocity follow-ups of transiting exoplanets

Presenter: Baptiste Klein


Transiting exoplanets are key targets to better understand the formation and evolution of planetary systems. On the one hand, one can estimate planetary radii using transit depths, while, on the other hand, the monitoring of the host star radial velocity (RV) with high-precision velocimeters allows to determine planetary masses. This allows for the estimation of planet bulk densities, yielding thus precious constraints on their inner compositions. However, precisely measuring the mass of earth-like planets is challenging given the low RV wobbles that they induce on the host star and the stellar magnetic activity whose RV signature frequently overwhelm the planetary signal. As a result, few planets with well-constrained bulk density populate the Mass-Radius diagram for Earth-analogs. The same goes for young close-in giants whose RV and photometric signatures are strongly inhibited by the intense magnetic activity exhibited by PMS stars. SPIRou is currently the best instrument worldwide to precisely determine the mass of transiting planetary systems around M dwarfs and PMS stars. Based on realistic simulations of RV follow-ups of TRAPPIST-1 and K2-33 planetary systems, we assess the ability of SPIRou to precisely retrieve the planet masses and show that the observational sampling plays a major role in the accuracy of the planet mass estimates for high-precision velocimeters like SPIRou.