Triply differential single ionization cross sections in coplanar and non-coplanar geometry for fast heavy ion-atom collisions

We have performed a kinematically complete experiment and calculations on s ingle ionization in 100 MeV/amu C6+ + He collisions. For electrons ejected into the scattering plane (defined by the initial and final projectile mome ntum vectors) our first- and higher-order calculations are in good agreemen t with the data. In the plane perpendicular to the scattering plane and con taining the initial projectile axis a strong forward-backward asymmetry is observed. In this plane both the first-order and the higher-order calculati ons do not provide good agreement neither with the data nor amongst each ot her.