Coulomb excitation of highly charged projectile ions in relativistic collisions with diatomic molecules

We investigate the Coulomb excitation of highly charged ions colliding with diatomic molecules. In this process, the coherent interaction between the projectile electron and two molecular centers may cause clear interference patterns in the (collision) energy dependencies of the total cross sections and alignment parameters. We discuss such a Young-type interference for the particular case of the K→L excitation of hydrogen- and helium-like projectile ions. Calculations, performed for the scattering of these ions on nitrogen molecules, indicate that the interference effects are extremely sensitive to the collisional geometry and are pronounced only if the molecular axis is aligned almost parallel to the incident beam trajectory.