My name is Ryan Cloutier and I am a fourth-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 le 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 employ statistical methods commonly used in machine learning to mitigate 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 sepctroscopy 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.
M dwarf stars are most efficiently observed at near-infrared wavelengths where their spectra peak and stellar absorption features, which are 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; near-infrared spectrographs whose observations I will use to both detect new exoplanetary systems as well as to characterize the masses of known transiting planetary systems thus constraining their bulk densities.
Click here for my list of publications on ADS.
Simulating the SPIRou Legacy Survey Planet-Search
In this paper we run 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 exoplanets. Our simulations consider the planet occurrence rates around M dwarfs, physical models of stellar activity, and uses our Gaussian process regression method to simultaneously model planets and activity.
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.
Detecting additional planets in the GJ 1132 planetary system
In this paper I describe the use of a trained mean Gaussian process regression model of the stellar activity in radial velocity. Here we applied this technique to the GJ 1132 planetary system to model the stellar activity and measure the detection completeness to additional planets hypothesized to exist within the system based on the high occurrence rate of planets around stars like GJ 1132.
This technique will prove to be useful when characterizing transiting planet candidates such as those that will be discovered with NASA's up-coming TESS mission. The mass characterization of these planets will be imperative to the interpretation of measurements of their atmospheres with the up-coming James Webb Space Telescope.
The following is a link to a PDF version of my full CV.