WFIRST Simulations

Wide-Field Infrared Survey Telescope

WFIRST Coronagraph Instrument (CGI) Exoplanet Albedo Spectra


The WFIRST coronagraph will observe exoplanets in reflected light at visible wavelengths. Therefore, in order to simulate the signals expected, realistic assumptions must be made about the exoplanet albedo spectra. In addition to providing inputs to WFIRST CGI IFS simulations, the simulated spectra can be used to assess the feasibility of discriminating exoplanet signals from that of background galaxies based on their expected broadband colors.

Radiative transfer calculations of reflected-light spectra for exoplanets with different atmospheric compositions and under different system geometries is an active area of investigation. On this page we host the products of some of these investigations - most notably, upcoming results from the WFIRST Preparatory Science awards (WPS) and Science Investigation Teams (SITs), as well as recent results from the wider exoplanet community of interest in the context of simulating WFIRST CGI observations.


Cahoy et al. 2010 Model

The exoplanet albedo spectra and colors have been calculated for Jupiter and Neptune analogs as a function of planet phase, separation from the host star, and metallicity by Cahoy et al. (2010). The resulting models (gzipped tar file) have been made available by Nikole Lewis (STScI). Please see the README file for information on the format and contents of the data files and for properly crediting the models.

Theoretical albedo spectrum example using data from the Cahoy et al. 2010 models. Simulations such as these are needed in order to assess the detectability of exoplanets in reflected light at visible wavelengths by the WFIRST Coronagraph Instrument, the feasibility of discriminating exoplanets from background stars and galaxies based on their expected broadband colors, and mission-level exoplanet yields.