Scatter from an Electron
| In 1906 J. J. Thompson showed that the scattered amplitude, y, from the interaction of unpolarized radiation of amplitude A and wavelength l with a free classical electron of charge e and mass m viewed at a distance R (R>>l) from the electron is |
| Here c is the velocity of light and the
term in brackets arises from a loss in amplitude due to the partial
polarization of the scattered beam. Though we are interested in
amplitude, note that the scattered intensity would be represented by the
square of this quantity, thus giving rise to the well recognized
1/R2 relationship between intensity and distance.
This relation shows that for a point electron there is no change in scattered amplitude (other than the polarization term) for changes in either wavelength or observation angle (q). |