text: In gamma spectrometry, the Compton edge is a feature of a detector output spectrum that results from Compton scattering in such as a scintillation detector or Photodiode detector. It occurs when a gamma-ray scatters within the detector and some of the interaction energy escapes so that only a fraction is detected. The amount of energy deposited in the detector depends on the scattering angle of the photon, leading to a spectrum of energies each corresponding to a different scattering angle. The highest energy that can be deposited, corresponding to full backscatter, is called the Compton edge. In mathematical terms, the Compton edge is the inflection point of the high-energy side of the Compton region.