Compton Scattering: What is the Difference from Electron-Photon Absorption?

[luxiaolei]

Hi all. Here is the question:

Compton scattering I understood is, any wavelength phton can kick an electron, hecnce change its momentum.

However, I also learned in the electron phton absorbtion process, if the photon's energy smaller than the energy difference between the two states of the electron, it will simply passing through electron.

What is the wrong here? Thanks a lot in advance.

 

[mathman]

There are many different processes where photons interact with matter.

 

[stephenhky]

The first one is basically a process between photons and a free electron or a free nucleus.

The second one is a quantum mechanical process between photons and an atom. When you say the energy difference between states of electron, I think you mean energy difference between states of the ATOM. Of course, the electrons are situated at different states in an atom.

 

[Dickfore]

Compton scattering is scattering off of free electrons. This means the electron can absorb an arbitrarily small quantum of energy (and momentum), so it is quite different from the resonance condition about photon absorption that you stated.

 

[huuha]

I need to find a number of calculated scattering cross section of Compton scattering before using quantum field theory.
anyone can help me? My email address is: nghuuha210@gmail.com