Collisions of mass-less particles with those of mass

[petrushka.googol]

What is the outcome of a collision between a photon and an electron ?

 

Please opine.

[Sensei]

You didn't said whether electron has to be free or bond to atom..

 

Here you have video summary of reactions between photons and electrons/atoms:

 

[imatfaal]

Momentum is conserved - photon momentum is well defined (and only depends on wavelength as a variable for the magnitude of the momentum). You can thus predict the outcome for a high energy photon hitting an elextron with a calculation based on Compton Scattering equations - or by using the momentum (relativistic) energy 4 vector and switching frames with lorentz transforms