Research on Cs Beam Frequency Standards at the PTB: Beam Optics, Majorana Transitions

Results on theoretical and experimental studies on Cs beam optics using quadrupole and hexapole magnets and a combination of both, are reported. The efficiency of the deflection system and the velocity distribution in the beam have been computed for extended beam sources and compared with experimental results. An appropriate combination of magnets yielded a strong beam with a narrow relative half-width velocity range of about 7 percent. Design problems of Cs standards are discussed. A new wedge-shaped analyzer flop-in magnet is under study. Frequency shifting effects due to Majorana transitions are reported and the frequency shifting mechanism is discussed.