The Roman Space Telescope Galaxy Survey Exposure Time Calculator is Chris Hirata's exposure time calculator for use in optimizing hardware requirements and observing strategy for the Roman Space Telescope High Latitude Survey (HLS). It takes known galaxy properties to predict the limiting magnitudes and statistical properties of sources that can be detected by Roman Space Telescope for gravitational weak lensing and the galaxy redshift survey. It also has modes to help with the photo-z calibration emission line sensitivities and with estimating the spectral continuum sensitivity. The current update (version 17) of this code incorporates new options for the BAO survey ([O II] and [O III] lines) and Fowler-4/Fowler-8 readout options. Four configuration files are now available, including the WFI direct imaging blue and red wavelengths, and the WFI grism and prism modes.
Pandeia, named for the Greek goddess of brightness, is a multi-mission exposure time calculator built at STScI to support JWST. Pandeia calculates a detailed and accurate system performance for a wide variety of science cases and includes support for direct imaging, slitless spectroscopy, IFC spectroscopy, and coronagraphy. It is not limited to calculations of a single source, and includes the ability to build complex astronomical scenes. STScI has extended Pandeia to support the Roman Space Telescope. It implements the current Roman Space Telescope optical reference information. Download instructions, tutorial notebooks, and references are available through a GitHub repository. Users are encouraged to address questions, suggestions, and bug reports to help@stsci.edu with "Pandeia-Roman question" in the subject line. The message will be directed to the appropriate members of the Pandeia-Roman team at STScI.