Nuclear interactions between inner zone protons and atoms in the upper
atmosphere produce energetic H and He nuclei that are an additional radiation
belt source. We calculate production rates of these isotopes from models of the
inner zone proton intensity, the upper atmosphere drift averaged composition and
densities, and cross-sections for the various interaction processes. For comparison
with observations of radiation belt H and He isotopes, the production rates are
combined with a model of the energy loss rate in the residual atmosphere to calculate
particle intensities. Although the calculations are in principle straightforward, they
depend on a detailed knowledge of the various model inputs, including models for
radiation belt protons, and may also depend on the phase of the solar cycle. On the
other hand, the results of the calculations, when compared with the observational
data, can provide useful tests of the model inputs. Preliminary results show that
the atmosphere is a significant source for inner zone ^4He, ^3He, and d
