Corrections to Laser Electron Thomson Scattering

Thomson scattering is the classical process of light being deflected by a charged obstacle of typical size smaller than the wavelength of the incident radiation. For definiteness we will henceforth assume the charge to be an electron and the incoming wave stemming from a laser beam. The scattered radiation may be viewed as resulting from a two-step process: (i) the acceleration of the charge due to the electromagnetic field it encounters and (ii) the bremsstrahlung emitted in consequence. (In fact, this is what happens when solving the classical equations in powers of the coupling: at zeroth order, there is only acceleration, while at first order, there is emission.) The instantaneously radiated power is then given by Larmor’s formula which, in its nonrelativistic incarnation and using Heaviside-Lorentz units, reads [1]