My name is Ryan Cloutier and I am a final-year PhD candidate in the Department of Astronomy and Astrophysics at the University of Toronto. I am also a Centre for Planetary Sciences Graduate Fellow doing my thesis with Professors Kristen Menou and René Doyon at l'Université de Montréal. As such, I am also affiliated with the Institute for Research on Exoplanets.
I am a member of the SPIRou and NIRPS science teams working on the radial velocity detection and characterization of exoplanets around M dwarf stars. I frequently employ statistical methods commonly used in machine learning to model the effects of stellar activity thus facilitating the detection of faint signals from small, Earth-like planets. My broad research interests include understanding the bulk properites of the sub-Neptune-sized exoplanet population which is informed by the continuing discovery of new exoplanets and by various observational opportunities afforded by certain exoplanets such as transmission spectroscopy and direct imaging of small planets in the coming decades. In practice I work on developing robust techniques to both detect large numbers of new exoplanets as well as to characterize known exoplanets such as those found in transit around their host star and those which may be amenable to atmospheric characterization.
most of my research revolves around the endeavour of detecting and characterizing Earth-like planets around nearby M dwarf stars using the radial velocity method.
Mid-to-late M dwarf stars in particular are most efficiently observed at near-infrared wavelengths where their brightness peaks and the stellar absorption features required to measure precise radial velocities are abundant. To conduct observations of nearby M dwarfs and search for faint planetary signals, a number of innovative instruments are currently being designed and built including SPIRou and NIRPS: high-resolution near-infrared spectrographs whose observations will be used to both detect new exoplanetary systems as well as to characterize the masses of known transiting planets.
Click here for my list of publications on ADS.
Quantifying the observational requirement for the RV characterization of transiting planets
In this paper we derived a model to calculate the number of measurements required to detect a transiting planet's radial velocity semi-amplitude at a given level of precision. Separate formalisms are presented in the presence of either correlated or uncorrelated noise.
We then calculated the observing time required to characterize the full expected TESS yield using either an optical or near-infrared spectrograph. As an example, we find that the efficient mass characterization of 50 TESS planets smaller than 4 Earth radii can be completed in as little as ~60 observing nights. We also describe how our calculations can be used to identify the 'best' transiting planets for RV follow-up observations based on the efficiency with which their masses can be measured.
The Radial Velocity Follow-up Calculator online tool is introduced which allows users to use our model to rapidly compute the observational requirement to detect any transiting planet's RV semi-amplitude with a user-defined spectrograph.
Simulating the SPIRou Legacy Survey-Planet Search
In this paper we ran a detailed Monte-Carlo simulation simulating the up-coming SPIRou Legacy Survey-Planet Search which will survey ~ 100 M dwarfs in the Northern sky searching for new exoplanetary systems. These simulations are based off of the measured planet occurrence rates around M dwarfs, physical models of stellar activity, and utilizes a Gaussian process regression method to simultaneously model planets and activity thus improving the survey sensitivity to small, Earth-like planets in particular.
We predict ~85 new exoplanetary detections including ~8 temperate planets with Earth-like masses, ~5 of which may be imagable with high-contrast imagers on the next generation of Extremely Large Telescopes.
Output stellar and planetary populations from our simulations are made available on github.
Characterizing the K2-18 multi-planetary system
In this paper we present our radial velocity characterization of the K2-18 planetary system using precision HARPS radial velocities. The system contains a known transiting super-Earth orbiting within the habitable zone of the nearby (34 pc) M dwarf K2-18. We measure a planet mass of 8 Earth masses and detect a second, non-transiting super-Earth whose orbit is interior to that of the known transiting planet.
The following is a link to a PDF version of my full CV.