  Pandeia is the exposure time calculator (ETC) system developed for the James
Webb Space Telescope (JWST) that will be used for creating JWST proposals. It
includes a simulation-hybrid Python engine that calculates the two-dimensional
pixel-by-pixel signal and noise properties of the JWST instruments. This allows
for appropriate handling of realistic point spread functions, MULTIACCUM
detector readouts, correlated detector readnoise, and multiple photometric and
spectral extraction strategies. Pandeia includes support for all the JWST
observing modes, including imaging, slitted/slitless spectroscopy, integral
field spectroscopy, and coronagraphy. Its highly modular, data-driven design
makes it easily adaptable to other observatories. An implementation for use
with WFIRST is also available.
