The cross sections for the double ionization of ${\mathrm{H}}_2$ by 0.025–0.875-MeV/amu ${\mathrm{He}}^{+}$ are reported for the ${\mathrm{H}}_2$ internuclear axis oriented at 90° and 30° relative to the ion-beam direction. At low projectile velocities, there is an apparent angular dependence for the cross section, with the 90° results being larger.

• Received 13 December 1984

DOI:https://doi.org/10.1103/PhysRevA.31.3972