Abstract
A phenomenological rate process theory is developed for the storage and rapid recombination of atomic hydrogen free radicals in a crystalline molecular hydrogen solid at temperatures in the range 0.1 K≲T≲4 K. It is shown that such a theory can account quantitatively for the recently observed dependence of the storage time on the storage temperature, for the maximum concentration of trapped H atoms, and for the time duration of the energy release in the tritium decay experiments of Webeler. The theory predicts that maximum atomic hydrogen concentrations of the order 1020/cm3 are realizable for storage temperatures in the vicinity of 0.14 K.