Lower, JulianWeigold, ErichBerakdar, J.Mazevet, S2015-12-102015-12-100031-9007http://hdl.handle.net/1885/70324Experimental results are discussed for (e, 2e) cross sections where the initiation state of the projectile-target system is completely resolved by employing a polarized electron beam and an atomic beam prepared in a well defined quantum state by laser pumping. The results show that the initial state resolved ionization cross section depends both on the relative spin projections of the incident and bound state electrons and on the orientation of the target electron.Keywords: Atomic beams; Degrees of freedom (mechanics); Electron beams; Electrons; Ionization; Ions; Kinematics; Mathematical models; Photoemission; Quantum theory; Distorted wave Born approximation; Final state continuum electrons; Spin polarized electrons; Valenc200110.1103/PhysRevLett.86.6242015-12-10