Vortices associated with the wave function of a single electron emitted in slow ion-atom collisions

Abstract

We present measurements and calculations of the momentum distribution of electrons emitted during the ion-atom collision 10 keV/u $H{e}^{2+}+He\to H{e}^{+}+H{e}^{2+}+e^{-}$, which show rich structures for ion scattering angles above 2 mrad arising dominantly from two-electron states. Our calculations reveal that minima in the measured distributions are zeros in the electronic probability density resulting from vortices in the electronic current.