Young-Type Interference in Projectile-Electron Loss in Energetic Ion-Molecule Collisions

Under certain conditions an electron bound in a fast projectile ion, colliding with a molecule, interacts mainly with the nuclei and inner shell electrons of atoms forming the molecule. Because of their compact localization in space and distinct separation from each other, these molecular centers play in such collisions a role similar to that of optical slits in light scattering leading to pronounced interference in the spectra of the electron emitted from the projectile.

Figure 1

The spectra of electrons (in a.u.) emitted into the plane spanned by the molecular axis and projectile velocity from $7.8\mathrm{MeV}/\mathrm{u}$ ${\mathrm{Mg}}^{11+}(1s)$ ions colliding with ${\mathrm{N}}_2$ molecules. The spectra (from left to right and from top to bottom) correspond to ${\vartheta }_M=90°$, 20°, 15°, 10°, 5°, and 0°. The angle ${\vartheta }_M$ is counted from the direction of the projectile velocity $\mathbf{v}$.

Figure 2

Energy spectrum of electrons emitted under the zero azimuthal angle from $7.8\mathrm{MeV}/\mathrm{u}$ ${\mathrm{Mg}}^{11+}(1s)$ ions colliding with ${\mathrm{N}}_2$. The spectrum is given in the projectile frame. Solid, dashed, and dotted curves correspond to collisions with the molecules oriented in the target frame under the polar angle ${\vartheta }_M=0°$, 5°, and 10°, respectively. For a comparison, the dash-dotted curve shows the spectrum in collisions with N atoms multiplied by 2.