Weak field radio-frequency transitions in H and D revisited

Weak-field radiofrequency transitions using the adiabatic-passage method play an important role e.g. in atomic-beam polarized atom and ion sources. The design criteria for the transition units may be optimized using the Majorana formalism together with semi-classical model considerations or by solving the time-dependent coupled Schrِdinger equations for the Zeeman hyperfine structure multiplets. Results for both are presented, especially the dependence of the polarization on the sign of the gradient of the static magnetic field and on the radio-frequency magnetic-field amplitude.