Recent progress on commissioning an optically pumped Cesium beam as primary frequency standard at Brazilian NMI

This paper describes the progress on commissioning a thermal Cesium beam frequency standard developed at IFSC-USP and transferred to the Brazilian NMI in order to be continuously operated as a primary frequency standard. The system is composed of a short Ramsey cavity for electromagnetic excitation and an optical pumping for atom detection and energy-state selection. The uncertainty budget for the measurement technique is under verification to acquire the same performance achieved earlier during the scientific development of the standard. Some aspects of the standard implantation are discussed here according to the technical and metrological requirements for the system.