Code to predict spectra for collisionally ionized plasma in the optically thin limit. (A replacement for the 1970's Raymond-Smith code.) The APEC FITS output files maintain individual information on all strong emission lines, continuum, and pseudo-continuum from many weak lines. See the ATOMDB site for more details on APEC. Using APEC on the APED will produce the ATOMDB.

APEC is available within Sherpa as the xsapec model and by using GUIDE.