ANALYSIS OF THE NOISE SOURCES IN AN OPTICALLY PUMPED CESIUM BEAM RESONATOR

We determine the main noise sources which affect the clock signal dete ction in an optically pumped cesium beam resonator and evaluate their influence on the clock S/N ratio. We take into account the following n oise sources: atomic shot noise, fluorescence photon noise, laser freq uency noise and clock signal detection noise. We have developed a theo retical model which predicts the variations of the S/N ratio as a func tion of different parameters characterizing the atom-laser interaction . The main conclusion concerns the saturation of S/N value for high at omic flux due to laser frequency fluctuations. All the theoretical pre dictions have been experimentally verified.