Simple photon power law.
where is the energy index of power law.
The user is cautioned that simple power laws can have unintended consequences owing to the fact that they are automatically extrapolated to the lowest (0.1 eV) and highest (1 MeV) energies employed in the calculation. This can cause processes such as stimulated recombination and Compton cooling to dominate the model results, and may not represent a physically realistic result. These effects can be avoided by the use of a simple file spectrum as demonstrated below.