Resonant-Transfer-and-Excitation for Highly Charged Ions (16 Less Than or Equal to Z Less Than or Equal to 23) in Collisions with Helium

摘要

Significant new evidence is presented for resonant-transfer-and-excitation (RTE) in ion-atom collisions. This process occurs when a target electron is captured simultaneously with the excitation of the projectile followed by deexcitation via photon emission. RTE, which is analogous to dielectronic recombination (DR), proceeds via the inverse of an Auger transition, and is expected to be resonant for projectile velocities corresponding to the energy of the ejected electron in the Auger process. RTE was investigated by measuring cross sections for projectile K x-ray emission coincident with single electron capture for 15 to 200 MeV sub 16 S exp 13+ , 100 to 360 MeV sub 20 Ca exp 16+ exp 17+ exp 18+ and 180 to 460 MeV sub 23 V exp 19+ exp 20+ exp 21+ ions colliding with helium. Strong resonant behavior, in agreement with theoretical calculations of RTE, was observed in the coincidence cross sections. (ERA citation 10:010492)