Two-centre dielectronic interaction in mutually ionizing projectile-target collisions at relativistic energies

We consider the process of mutual projectile-target ionization in relativistic collisions between light hydrogen-like ions and hydrogen and helium atoms: (i) XZ+(1s) + H(1s) → X(Z+1)+ + H+ + 2e- and (ii) XZ+(1s) + He(1s2) → X(Z+1)+ + He+(1s) + 2e-. At high collision velocities and for not too heavy projectiles, where Z/v << 1 with v being the collision velocity, mutual ionization proceeds via the two-centre dielectronic interaction (TCDI) which couples two electrons initially bound in the different colliding particles. Several aspects of electron emission from the target are explored in detail for the case when the final internal continuum state of the projectile is not detected, i.e. when the integration is performed in calculations over all possible final continuum states of the electron ejected from the projectile. Our results show that the relativistic effects in the TCDI clearly manifest themselves in the spectra of electrons emitted from the target. The character and magnitude of these manifestations suggest that these effects are quite accessible for experimental observations