Date/Time
Date(s) - 29/03/2023
3:30 pm - 4:30 pm

Guest: Dr. David Lafreniere
https://exoplanetes.umontreal.ca/en/team-member/david-lafreniere/

Host: Dr. Ryan Cloutier

Title: A first look at exoplanet atmospheres with JWST NIRISS

Abstract:
Radial velocity and transit surveys have revealed that exoplanets are ubiquitous in our Galaxy and much more diversified than expected, pointing to the existence of various planetary formation and evolution pathways as well as a wide range of planetary conditions and dynamics. Spectroscopy of transiting exoplanet atmospheres is a crucial component of all the efforts now being made to expose this diversity in full and understand its origins, and the newly operational JWST will be at the forefront of this work for the coming decade. With this goal, our group is leading the NIRISS Exploration of the Atmospheres of Transiting exoplanets (NEAT) program, a large JWST program targeting 15 transiting exoplanets spanning a wide range of equilibrium temperatures (300-3000 K) and masses (1 MEarth-10 MJup), to measure the abundance of the molecules and aerosols present in the exoplanets’ atmosphere, constrain the presence of clouds and, for the hottest targets, determine their vertical temperature structure and overall dynamics. In this talk, based on the first data sets received over the past several months, I will show the excellent performance of the JWST observatory and NIRISS instrument for transiting exoplanet spectroscopy, discuss the challenges of making atmosphere measurements at the highest precision level, and present results for some of our first observed targets, including two hot Jupiters, a hot Neptune and a temperate rocky planet.