Progress at CENAM to Develop a Cs Fountain Frequency Standard

The Centro Nacional de Metrologia, CENAM, is currently developing a Cs fountain primary frequency standard, which is referred as CsF-1, with the aim to experimentally realize the unit of time with an uncertainty of parts in 10 15 or better. Currently, the Magneto-Optical Trapp (MOT) of the CsF-1 is under routinely operation, its characterization has been done as function of its operational parameters. When writing this article the vacuum tube of the flight region is under construction. A threefold magnetic shielding has been designed and constructed. Sapphire oscillators to be used as local oscillator at the CsF-1 have been also designed, assembled and characterized.