X-Ray Scattering from an Electron Gas

We show that the x-ray scattering from an electron gas in the large-momentum-transfer regime ($k\ensuremath{\gg}\frac{{P}_{F}}{\ensuremath{\hbar}}$) is a direct measure of the one-dimensional momentum distribution of the particles (including correlations). If the recoiling electron's momentum is measured in coincidence with the scattered x ray, then one can (in principle) measure the complete three-dimensional momentum distribution function.