Autoionization of He by partially stripped ion impact*

The autoionization of He by ion impact can be considered a two step process in which the atom is first excited to an autoionizing state and afterwards decays emitting one electron to the continuum. Several theoretical methods have been developed in order to predict the position of the autoionization peak and the profile of the ``Coulomb focusing peak.'' For the latter, the enhancement in the impinging ion direction arises by the postcollisional interaction between the emitted electron and the receding projectile. Previous studies have considered He$^{+}$ projectiles with a pure Coulomb potential. In this work, we present the new features that partially stripped ions will leave on the main visible structures of the doubly differential cross sections (i.e. the autoionization and binary rings). These energy and angular profiles are also compared with those obtained with pure Coulombic ions.