  The James Webb Space Telescope (JWST) will devote significant observing time
to the study of exoplanets. It will not be serviceable as was the Hubble Space
Telescope, and therefore the spacecraft/instruments will have a relatively
limited life. It is important to get as much science as possible out of this
limited observing time. We provide an analysis framework (including publicly
released computational tools) that can be used to optimize lists of exoplanet
targets for atmospheric characterization. Our tools take catalogs of planet
detections, either simulated, or actual; categorize the targets by planet
radius and equilibrium temperature; estimate planet masses; generate model
spectra and simulated instrument spectra; perform a statistical analysis to
determine if the instrument spectra can confirm an atmospheric detection; and
finally, rank the targets within each category by observation time required.
For a catalog of simulated Transiting Exoplanet Survey Satellite planet
detections, we determine an optimal target ranking for the observing time
available. Our results are generally consistent with other recent studies of
JWST exoplanet target optimization. We show that assumptions about target
planet atmospheric metallicity, instrument performance (especially the noise
floor), and statistical detection threshold, can have a significant effect on
target ranking. Over its full 10-year (fuel-limited) mission, JWST has the
potential to increase the number of atmospheres characterized by transmission
spectroscopy by an order of magnitude (from about 50 currently to between 400
and 500).
