Electron capture in collisions ofN5+ions with H atoms from the meV to keV energy regions

Abstract

Quantum-mechanical and semiclassical molecular-orbital expansion methods are employed to investigate a single-electron-capture mechanism in N'++8 collisions in the energy range from 10 meV/amu to 10 keV/amu.The dominant electron-capture channels in the entire regime are found to be N +(4s), N +(4p), and to some extent N +(4d ). The N +(4f ) channel is found to make small contributions at any energy because of its near diabaticity with respect to the initial channel. Agreement for total and n-shell captures with recent measurements is excellent in the entire energy regime, and agreement for l-shell capture with measurements is reasonable for most cases. Furthermore, several shape resonances due to rovibrational states of the transient quasimolecule are found below 1 eV, and a large, broad structure arising from trajectory effects due to the weak attractive polarization potential is found below 60 meV/amu. The origins of differences between the present results and the measurements and other theoretical calculations are also discussed.

Resonances in electron-capture total cross sections forC4+andB5+collisi

“…Other works [4,14,15] have found similar resonant structures in close-coupling calculations. However, as pointed out in Ref.…”

“…[4,13,14]) that, for E < 0.1 eV/amu, the EC cross section exhibits sharp peaks for systems where the adiabatic potential of the entrance channel has a minimum. In these cases, the effective potentials for the nuclear motion can support several predissociating states for each value of the angular quantum number J .…”

“…The (14)] to those of the quasistationary states calculated using the phase-amplitude (PA) method [26] and applying the program LEVEL [25]. …”

Molecular treatment of electron capture at low to intermediate collision energies: Collisions ofB4+ions with H atoms

“…(C ++H) system:---Fritsch and Lin [19]. Be +: Fritsch and Lin [18]; B:present; C +: Fritsch and Lin [19]; N +: Shimakura, Itoh, and Kimura [4]; B +: Fritsch and Lin [18]; C +: Shimakura et al [2]; N' Shimakura and Kimura [1]. universality of the scaling rule.…”

“…Those channels consist of seven X, four II, and one 6 state from the initial, 8 +(ls4s), 8 +(ls4p) (for triplet), 8 +(ls4f) (for singlet), and all 8 +( lsnl, n =2 and 3) manifolds listed in Table II. As described in our previous papers [1,2,4], we used both straight-line and repulsive Coulomb trajectories for heavy-particle motion in order to examine the trajectory effect on the transition probabilities.…”