Momentum spectroscopy in ion-atom collision

Abstract

In this article, we review the recent progress in the field of momentum spectroscopy in fast-ion atom ionization based on the measurements of electron double differential cross section (DDCS). It is shown that the energy and angular distributions of the low energy electron emission not only provide informations on two center effects but also can be used to study the final-state longitudinal momentum distributions of the electrons, recoil-ions and projectiles. To demonstrate this we have used the recently measured data of low energy electron DDCS for three collision systems: C6++He/H2 (v=10) and p+H (v=2.14). The complementary nature of the electron spectroscopy and the recoil-ion momentum spectroscopy (RIMS) have been investigated using a new formulation based on three-body kinematics to explore the ionization dynamics in detail. The separation of the soft and hard collision branches of recoil-ion distributions is a novel feature of the present technique. Atomic units are used unless specified.