Differences between ATOMDB Version 1.2.0 and Raymond-Smith
The APEC outputs should be viewed as the replacement for the Raymond-Smith code. At high spectral resolution, the Raymond-Smith code is not usable because the emission lines are not calculated in fine structure (i.e. they are calculated via line bundling). However, gross features, such as radiated power as a function of temperature (i.e. the cooling curves) are not significantly different. However, even at moderate (CCD) resolution, there are significant differences between APEC V1.2.0 and the Raymond-Smith model implemented in public fitting packages, due to different models for ionization balance, fine structure and atomic data. The most important differences are for iron, shown here for binned spectra at different temperatures.
ATOMDB and Raymond-Smith Iron line spectra between Log T=6.3 - 7.8 in Wavelength units:
And in Energy (keV) units:
