Calculated gamma-ray spectrum for the specific case of Cas A using the assumptions described in the text. 10⁶ photons are binned into energy intervals of widths ranging from 2 to 5 keV as described in Ramaty et al. (1979). For example, the ¹²C line at 4.4   MeV has a flux that is comparable to the sensitivity of COMPTEL. Note that the continuum component caused by nonthermal electron bremsstrahlung is not taken into consideration here.