The Landau-Pomeranchuk-Migdal effect in QED
  The calculation of the radiative energy loss encountered by a fast charged particle which undergoes multiple scattering is being investigated. A detailed derivation of the Landau-Pomeranchuk-Migdal coherent effect in QED is given, focusing on the specific feature of the Coulomb interaction. As a result the radiation intensity per unit length in the coherent regime is shown to be proportional to $\sqrt \omega$ for a photon energy $\omega$ times a logarithmic enhancement which is determined exactly. 
R.Baier, Yu.L.Dokshitzer, A.H.Mueller, S.Peigne, D.Schiff