I am trying to calculate the energy at which the Compton edge occurs for a sample of Cs137 using a NaI(Tl) scintillator. I know the original energy of the gamma ray was 661.6keV. and that for the Compton edge the angle between the electron and the line of incident must be 0degrees (for max energy of photon). but this just give the value of the photopeak (incident gamma ray).(adsbygoogle = window.adsbygoogle || []).push({}); How do i calculate the energy of the emitted photons from Compton scattering at the Compton edge??

[i have calculated the beginning of the Compton continuum using an angle of 180 degrees between the electron and line of incident (minimum energy of the photon) and this gives a value which is about the same as my graph]

i have looked at a few sites but am fairly confused as to why the Compton edge is at a lower energy to the initial gamma ray photon.

Many thanks

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# Homework Help: Scintillator Compton Edge

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