Electron correlation in the continuum: Thee-2eprocess for small relative momenta of the outgoing electrons

Abstract
We present measured triply differential cross sections for the ejection of two electrons into the forward direction following impact of 400-, 600-, and 1000-eV electrons on helium atoms. The coplanar, symmetric geometry was used with a scattering angle of 4°. A comparison with our theoretical calculations demonstrates the clear effect of the final-state electron-electron correlation in fast electron-atom ionizing collisions.