## Charge exchange cross sections

The data sets provide principally nl-resolved charge exchange cross-sections over a range of n-shells for a donor neutral atom (typically hydrogen) colliding with an ionised impurity receiver as a function of normalised collision energy (keV/amu). The reaction is $X^{z+} + H_{n^\prime}^{0} \rightarrow X_{nl}^{(z-1)+} + H^{+}$

The data include summed cross-sections to whole n-shells and the total cross-section summed over all n-shells. The data may be used for any of the hydrogen isotopes. Parameters are usually also present which represent the cross-sections at high n-shells outside the tabular range and asymptotically at high collision energy. The energy ranges are suited to neutral beam studies and are generally too high for relevance to thermal charge transfer. The receiving ions are, for the most part, the bare nuclei of light elements up to neon. The donor states of hydrogen include the ground state and may include n'=2 and 3 states. There are a smaller number of data sets in which neutral helium, lithium and sodium are the donors. Normally the data sets are used in collisional–radiative models of the emissivities (including emissivities in the visible wavelength range) of the receiver as driven by the charge exchange. These derived data, which are more suited to spectroscopic interpretation of charge exchange signals, are tabulated in ADF12.