Hahn was a postdoc working under Hosdtadter at Stanford. Basically, they threw electrons really fast at atoms. By using a charged point particle (the electron), a lot about the nucleus of the atom can be determined. These types of experiments led to the dicovery of the proton and the neutron (this was before Hosdtadter).

Hosdtadter used electron scattering to investigate the charge distribution in nuclei and the structure of the proton and neutron. He was awarded the Nobel Prize in 1961 for this work.

Most of the papers are in Physical Review (before it split into A,B,C, etc.). However, here are some general articles on electron scattering:

http://en.wikipedia.org/wiki/Electron_scattering
http://hyperphysics.phy-astr.gsu.edu/hb … escat.html