Laser-induced charge transfer in the HeH+2 and H2+ quasimolecules

The cross sections for laser-induced charge transfer during the collisions of He+2 and H+ ions with hydrogen atoms are calculated. The electron transfer is into the n = 2 excited levels of the incident ions. Using the exact energy levels and dipole moments of the one-electron diatomic molecule, the cross sections are found to be broad functions of the wavelength of the pumping laser. For a focused laser intensity of 1012 W/cm2 at a wavelength corresponding to the third harmonic of the Nd-glass laser, the calculated charge transfer cross section is greater than 10−15 cm2 for the case of He+2 incident on hydrogen. The photon-induced cross section is largest at low collision velocities where the competing collision-induced reaction is negligible.