Comptonization of a seed spectrum

An empirical convolution model of Comptonization in which a fraction of the photons in an input seed spectrum is scattered into a power-law component. The model is described in Steiner et al. (2008, in prep), with details related to the XSPEC implementation given in the appendix. It is designed for soft plasmas which are not Compton thick, and Gamma>1. When using this model, it may be necessary to extend the energy grid over which the model is calculated. This can be accomplished using the energies command.

par1 = Gamma, the photon power-law index.
par2 = the scattered fraction. This should be bounded between 0 and 1.
par3 = a flag to switch between up-scattering only (>0) and both up- and down-scattering (<=0).

The source code file required is simpl.f with the parameter information in simpl_lmodel.dat.