Eur. Phys. J. D 38, 59-64 (2006)
https://doi.org/10.1140/epjd/e2005-00327-x

Angular dependence of double electron capture in collisions of C⁴⁺ with He

Stueckelberg oscillations in the differential cross-section for capture into C²⁺(1s²2s^{2 1}S)

¹ Max Planck Institute for the Physics of Complex Systems, Nöthnitzer Str. 38, 01187 Dresden, Germany
² Computer Center, Hitotsubashi University, Kunitachi, Tokyo, 186-8601, Japan
³ Graduate School of Sciences, Kyushu University, Fukuoka, 812-8581, Japan
⁴ Fachbereich C-Mathematik und Naturwissenschaften, Bergische Universität Wuppertal, 42119 Wuppertal, Germany
⁵ Department of Physics, Sophia University, 7-1 Kioicho, Tokyo, 102-8554, Japan
⁶ RIKEN, 2-1 Hirosawa, Wako, 351-0198, Japan

Corresponding author: ^a lukas@pichl.jp

Received: 2 August 2005
Revised: 28 October 2005
Published online: 13 December 2005

Abstract

In charge-transfer collisions of C⁴⁺(1s^{2 1}S) with He (1s^{2 1}S), the process of double electron capture into the ground state C²⁺ is well-known to dominate other channels by an order of magnitude for projectile energies below 10 keV. This work presents a calculation of differential cross-sections resolved in the angle and energy gain variables, based on an ab initio treatment of electronic states, and compares with the measurements published in the literature (projectile energy E=270, 400, and 470 eV). We also briefly discuss the semi-empirical two-state models developed by experimentalists for this process.