HYPERFINE STATE SELECTION OF HYDROGEN ATOMS BY LONGITUDINAL PERIODIC-FIELD MAGNETIC LENSES

Optical properties of a longitudinal periodic-field magnetic lens associated with a source of hydrogen atoms are studied. With the help of hydrogen atom dynamics, it is shown that the lens is equivalent to a (transverse field) six-pole magnet and that it could possibly be used for state selection of atoms in different devices (hydrogen maser, polarized ion sources). Using this equivalence, optical elements of the lens are calculated and their numerical values compared with those given by a precise determination of atomic trajectories. Particular attention is given to the problem of depolarization of atoms caused by successive crossings of the weak field regions in the lens. It is shown there that the depolarization rate is practically negligible. © 1969.