Interatomic potentials, hyperfine structure line shifts and diffusion coefficients of rubidium and cesium atoms in buffer helium

Rb and Cs atoms are considered in the buffer helium atmosphere. Interatomic potentials, diffusion coefficients, transport cross sections and hyperfine structure line shifts of these atoms are calculated. The investigations have been carried out in the range of intermediate interatomic distances at the temperature of 173-673 K. The problem has been solved by the methods of exchange perturbation theory. The exchange perturbation theory sums have been calculated by the commutator method. Hyperfine structure line shift of Rb and Cs atoms has been calculated in the hard core approximation. The wave function of the valent electron basic state necessary for calculations has been determined. The results obtained are presented in tables. It is established that a local shift and interatomic potential strongly depend on the selection of the wave function asymptotics. From the comparison of teoretical and experimental values of diffusion coefficients and transport cross sections for calculated potentials in can be seen that results of theory and experiment differ not more than 1.5 times