# Mott Scattering

I had this old homework that I never completely understood. A scatterng experiment is performed with electrons ($$E_0=450$$MeV) colliding at an atomic nucleus.
Following form factor is measured $$\left |F(q) \right |^2$$

My problem is that I don't know how to interpret this picture or for that matter,
what the formfactor $$\left |F(q) \right |^2$$ represents. ## 1 Answer

In the Breit Frame, where the spatial momentum of the nucleus is exactly reversed by the collision with the electron, the Form Factor can be interpreted as the Fourier transform of the electric charge density of the nucleus. If the Form Factor has mild dependance on $$q$$, the more concentrated in space the charge density is. Also the definition of the charge radius of a nucleus, or a proton for example, is done in terms of the derivative of the Form Factor at the origin. The different peaks would tell you about which spatial frequencies are the most important in the charge distribution.

Also you can check out this https://www.physics.umd.edu/courses/Phys741/xji/chapter4.pdf pg. 63 and 64.

• Thank you great answer now its clearer – Alessio Popovic Jun 28 at 7:04