compST: Comptonization, Sunyaev & Titarchuk

A Comptonization spectrum after Sunyaev and Titarchuk 1980, A&A, 86, 121. This model is the Comptonization of cool photons on hot electrons.

par1 | temperature in keV |

par2 | optical depth |

norm | , where is the total number of photons from the source, is the distance to the source, f is the factor , is the spectral index, is the injected photon energy in units of the temperature, and is the incomplete gamma function. |