ELECTRON-CAPTURE CROSS-SECTION AT NEAR-THERMAL COLLISION ENERGIES FORSI4++D

Using a merged-beams technique, absolute total electron-capture cross sections have been measured in the thermal energy regime for collision s of Si4+ ions with neutral D atoms. State-of-the-art molecular-orbita l coupled-channel calculations for the Si4++H(D) systems are compared to the measurements on an absolute scale. Both the existence of a surp risingly large kinematic isotope effect and an observed sharp low-ener gy increase of the cross section are attributed to trajectory effects due to an attractive ion-induced dipole.