Abstract

Characterization of exoplanets with NIRISS

David Lafrenière (Université de Montréal - iREx)

NIRISS Science team

This talk will present a brief overview of the capabilities of the Near-Infrared Imager and Slitless Spectrograph (NIRISS) onboard the James Webb Space Telescope for the study of exoplanets, as well as the broad lines of the exoplanet component of the Guaranteed Time Observation program of the NIRISS science team. The Single Object Slitless Spectroscopy (SOSS) mode of NIRISS, specialized for transiting exoplanet spectroscopy, provides a resolving power of 500-1400 across the 0.6-2.8 um range simultaneously. Observations of exoplanet in transits using SOSS should typically reach a precision of several tens of ppm per resolution element over a single transit. NIRISS SOSS is thus a unique and very powerful mode for the atmospheric characterization of transiting exoplanets, from hot Jupiters to super-Earths. NIRISS also features an aperture masking interferometry (AMI) mode that will enable moderate-contrast (<9 mag) imaging observations of faint companions at small angular separations (0.05”-0.4”) from their host star in the 3.6-5.0 um range; this mode reaches closer-in than the telescope diffraction limit. It will enable flux measurements of known exoplanets not observable at these wavelengths from the ground, as well as searching for planets around stars not amenable to ground-based extreme adaptive optics observations.

Talk