Nuclear spins and magnetic moments of some cesium isotopes

Abstract Using an atomic-beam magnetic resonance apparatus connected on-line with the ISOLDE isotope separator, CERN, hyperfine structure measurements have been performed in the 2 S 1 2 electronic ground state of some cesium isotopes. An on-line oven system which efficiently converts a mass separated ion beam of alkali isotopes to an atomic beam is described in some detail. Experimentally determined nuclear spins of 120, 121, 121m, 122, 122m, 123, 124, 126, 128, 130m, 135m Cs, the isomer of 121 Cs being discovered in this work, and magnetic moments of 121, 122, 123, 124, 126, 128, 130, 130m Cs are reported and discussed in terms of different nuclear models. The experimental data indicate deformed nuclear shapes of the lightest cesium isotopes.