Question

Find the maximum fractional energy loss (ΔE/E), for E=0.60MeV gamma ray that is Compton scattered from a free electron. State your answer to the nearest thousandth of a unit.

Answer 1

The change in the photon wavelength during Compton's scattering is given by:

Here

• h=6.63×10−34 J⋅s is the Plank's constant;
• c=3×108 m/s is the speed of light;

• m is the mass of the particle;

• θ is the scattering angle;

The maximum energy change corresponds to the backward scattering (θ=180∘θ=180∘).

In terms of Energy E, where λ=hc/E :

For the scattering on the electron, we get:

• mc^2=0.511 MeV is the rest-mass energy of the electron;

Then, the maximum fractional energy loss of the photon during Compton scattering is: