Single- and double-charge-exchange cross sections forArq++H2

Abstract

The cross sections for single-electron capture, including transfer ionization, and for double-electron capture, have been measured for Ar~++ H& for q =6, 7, 8, 9, and 11 with projectile energies from q eV to q keV. Theoretically, the cross sections for Ar + and Ar'+ impact were calculated using a molecularorbital expansion method in the energy region from 240 eV to 80 keV, and are in good agreement with experiment. The single-electron-capture cross sections were found to be more than one order of magnitude larger than those for double capture in both experiment and theory. The single-electron-capture cross sections were also compared to the Langevin cross section, a scaling law developed by Muller and Salzborn [Phys. Lett. 62A, 391 (1977)],and the absorbing sphere model. PACS number(s): 34.70. +e

Measurement of charge exchange cross sections for highly charged xenon and thorium ions with molecular hydrogen in a Penning Ion Trap

“…Since the Xe44+ measurements were repeated at the end of the experiment (right after the Ar11+ calibration) the uncertainty for the Xe44+ cross section is assumed to be the same as for the thorium. was taken from the Kravis et al data [3], The fit value of a was 1.2. Since the sources of error were mostly systematic rather than random, it is difficult to put an uncertainty on the value of a.…”

“…Charge transfer measurements have also been made using ion beams. These experiments are usually made at relatively high energy (lOkeV / a.m.u is considered "low energy"), although a few measurements have been made at less than leV [2], [3], These, however, used ions of charge 11+ or less.…”

“…Ar11+ was chosen because a preprint (now published [3] ) had been made available to the RETRAP group giving cross section dependence on energy over a wide range, which included the energy range of stored ions in RETRAP. Also, the charge to mass ratio is fairly near that of the highly charged ions of interest in RETRAP (m/q is 3.63 for Ar11+, 3.09 for Xe" +, 3.22 for Th72+, and 2.93 for Th79+).…”

On the semiclassical approach in the theory of ion–diatomic exchange interaction: its application to charge exchange reactions

“…At asymptotically large distances R 2n 2 a Z b and the additional assumption Z a ∼ Z b , equation (27) goes over into the following form:…”

“…For the single electron capture H 2 [ 1 + g ] + Ar 6+ → H + 2 (1sσ ) + Ar 5+ (n m), our basis includes the following electronic states of the quasimolecule [ArH 2 ] 6+ : (i) the entrance channel H 2 [ 1 + g ] + Ar 6+ ; (ii) 17 final states which dissociate into H + 2 (1sσ ) + Ar 5+ (n m), n = 3, 4, 5, 6; m = 0. Our total cross sections σ tot are plotted in figure 2(a), compared with experimental data of [27,28] and MO-calculations of [27]. In figure 2(b) we present the total cross sections σ n for the electron capture into the manifold The total cross sections for single electron capture in H 2 + Ar 6+ collision.…”