  The momentum distribution of the electron in the reaction p+He $\rightarrow$
H + He$^{2+}$ + $e$ is measured for projectile energies $E_p$=300 and 630 keV/u
at very small scattering angles of hydrogen. We mainly present two dimensional
distributions parallel $(k_{||})$ and perpendicular $(k_{\perp})$ to the
projectile beam. Theoretical calculations were carried out within the Plane
Wave First Born Approximation (PWFBA), which includes both electron emission
mechanisms, shake-off and sequential capture and ionization. It is shown that
electron correlations in the target wave function play the most important role
in the explanation of experimentally observed backward emission. Second order
effects have to be involved to correctly describe the forward emission of the
electron.
