Electron capture by N$^{6+}$ in collisions with atomic hydrogen*

Charge transfer due to collisions of ground state N$^{6+}$($1s~^2S$) with atomic hydrogen has been investigated using a variety of theoretical and experimental approaches. Total, $n$-, $\ell$-, and $S$-resolved cross sections are obtained and compared to the limited available data for collision energies between 10 meV/u and 25 keV/u. The quantum-mechanical molecular-orbital close-coupling (QMOCC), classical trajectory Monte Carlo, atomic-orbital close-coupling, and multichannel Landau-Zener methods are applied in order to cover the large range of considered collision energies. The QMOCC calculations utilized adiabatic potential and nonadiabatic couplings obtained with the multi-reference single- and double-excitation configuration interaction approach. In particular, we focus on the triplet-singlet cross section ratios as they have the potential to influence x-ray emission predictions for heliospheric and Martian exosphere spectra due to $\sim$1 keV/u solar wind ion collisions. The absolute total cross sections are constrained by ion-atom merged-beams measurements.