Consider compton scattering with visible light. a photon with wavelength 500nm scatters backward(theta=180degree) from a free electron initially at rest. what is the fractional shift in wavelength delta\lamda/\lamda for the photon?

Explanation:

The Compton Shift in wavelength when photons are scattered is given by the following equation:

(1)  

Where:  

is the wavelength of the scattered photon

 is the wavelength of the incident photon

is a constant whose value is given by , being the Planck constant, the mass of the electron and the speed of light in vacuum.  

the angle between incident phhoton and the scatered photon.  

(2)

(3)  This is the shift in wavelength