Single-electron transfer from helium atoms to energetic multiply-charged nuclei

Abstract

The three-body boundary-corrected continuum intermediate state (BCIS-3B) method is employed to compute single-electron capture cross sections. These data are for collisions in which a target helium atom in its ground state He(1s2) is impacted by multiply charged nuclei (specifically H+,He2+,Li3+,Be4+,B5+,C6+,N7+,O8+,F9+). Intermediate and high projectile energies are considered (20 keV/amu-3 MeV/amu). The obtained results are tabulated for total cross sections (state-selective Qnlm as well as state-summed Qnl,Qn and QΣ). Cross section Qnlm corresponds to a fixed triple of the hydrogenlike quantum numbers {n,l,m}. In Qnl,Qn and QΣ, the sums over m∈[−l,l],l∈[0,n−1] and n∈[1,nmax] are carried out, respectively. For n>nmax in QΣ, the Oppenheimer n−3 scaling rule is adopted. The values of nmax are set to 4 (for H+,He2+,Li3+), 5 (for Be4+), 6 (for B5+) and 7 (for C6+,N7+,O8+,F9+). Exhaustive comparisons of the theoretical findings for QΣ with the corresponding experimental data are performed. It is determined that the BCIS-3B method is in excellent agreement with the available measurements. The present database for the examined capture processes is deemed to be of notable practical usefulness in versatile applications of particular relevance to plasma physics, astrophysics, fusion research and ion therapy in medicine.