The Coulomb-Born approximation has been employed to study charge transfer cross sections in the case of collisions of Be q+ (q = 1-3) and B q+ (q = 1-4) with atomic hydrogen in its ground state, respectively, within the energy range of 25-200 keV amu −1 . The interaction of the active electron with the incoming projectile ion has been approximated by a model potential. Cross sections for capture into different sub-shells have been given in tabular form. Computed total capture cross sections compare favourably with existing available results.

We show that the fluorescence emission spectrum of few atoms can be measured by using an optical nanofiber combined with the optical heterodyne and photon correlation spectroscopy. The observed fluorescence spectrum of the atoms near the nanofiber shows negligible effects of the atom-surface interaction and agrees well with the Mollow triplet spectrum of free-space atoms at high excitation intensity.

Charge-transfer cross sections into different subshells of C qϩ , N qϩ , and O qϩ (qϭ1 -5) from atomic hydrogen in the ground state have been calculated in the framework of the boundary corrected continuum intermediate-state approximation in the energy range of 40-200 keV/amu. Interactions of the active electron with the projectile ion have been approximated by a model potential containing both a long-range Coulomb potential part and a short-range part. Total cross-section results for all the ions are in reasonable agreement with available experimental results. However, oscillatory structure of charge-state dependence of total cross sections has not been found in our calculation.