Question

Calculate the energy of a 1 MeV gamma-ray photon after Compton scattering through 90 degrees

Answer 1

Gives

Energy of gamma photon

$E_\gamma=1MeV=1.6\times10^{-13}$

$\phi=90°$

$E_e=0.511MeV$

$K=\frac{hv\alpha(1-cos\phi)}{1+\alpha(1-cos\phi)}$

Where

$$\alpha=\frac{hv}{m_0c^2}=\frac{1MeV}{0.511MeV}=1.96$$

put alpha value

$$K=\frac{1.6\times10^{-13}\times1.96\times(1-cos90°)}{1+1.96\times(1-cos90°)}=1.05\times10^{-13}J$$