Editing Bremsstrahlung (section)

== Electron–electron bremsstrahlung ==
One mechanism, considered important for small atomic numbers {{nowrap|<math>Z</math>,}} is the scattering of a free electron at the shell electrons of an atom or molecule.<ref>{{cite journal |last1=Tessier |first1=F. |last2=Kawrakow |first2=I. |year=2008 |title=Calculation of the electron-electron bremsstrahlung crosssection in the field of atomic electrons |journal= Nuclear Instruments and Methods in Physics Research B|volume=266 |issue=4 |pages=625–634 |doi=10.1016/j.nimb.2007.11.063 |bibcode=2008NIMPB.266..625T }}</ref> Since electron–electron bremsstrahlung is a function of <math>Z</math> and the usual electron-nucleus bremsstrahlung is a function of {{nowrap|<math>Z^2</math>,}} electron–electron bremsstrahlung is negligible for metals. For air, however, it plays an important role in the production of [[terrestrial gamma-ray flashes]].<ref>{{cite journal |last1=Köhn |first1=C. |last2=Ebert |first2=U.|author2-link= Ute Ebert |title=The importance of electron-electron bremsstrahlung for terrestrial gamma-ray flashes, electron beams and electron-positron beams |journal= Journal of Physics D |year=2014 |volume=47 |issue=25 |pages=252001 |doi=10.1088/0022-3727/47/25/252001 |bibcode=2014JPhD...47y2001K |s2cid=7824294 |url=https://ir.cwi.nl/pub/22530 }}</ref>