(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Gamma rays of energy 1.02 MeV are scattered from electrons that are initially at rest. If the

scattering is symmetric, that is, if θ = ϕ in Fig. 1, find

i. the scattering angle θ

ii. the energy of the scattered photons.

2. Relevant equations

λ' - λ = (h/mc)[1 - cos(θ)]

3. The attempt at a solution

I'm not entirely sure where to go on this one. The first thing I did was take the energy of the gamma ray and find its wavelength via the relationship:

E = hf

E = hc/λ

λ = hc/E

λ = 1.217E-22 m

I've been scouring every resource I can but I cannot find a relationship for scattering angle dealing only with energy. I am certain that the fact that the scattering is symmetric has something to do with it, but I do not know how to apply that fact.

Does anyone know how I can approach this problem?

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# Compton Scattering: Finding Angle from only Initial Energy

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