1. N.F. Ramsey:Molecular Beams (Oxford Univ. Press, New York London 1956)
2. A. N. Orayevsky: IEEE Trans. IM-17, 346 (1968)
3. V. S. Letokhov, B. D. Pavlik: Opt. Spektr.32, 856, 1057 (1972)
4. For real light rays the width of the distribution function of excited atoms after transit through two separated waves corresponds, to the width of “Bennett's hole” Δυz∼1/kτ that is Δx∼d
5. Note that for one atom with a fixed velocity υz, the Ramsey resonance appears at interaction with two widely separated rays in linear approximation. The quantity and sign of the absorbed energy depend on the phases of the first and the second rays at points Z1 and Z2, respectively. When applied to the optical region, the energy is a rapidly oscillating function of υz with zero mean value