Abstract：In the cesium fountain clock experiment, the magnetic uniformity of C field determines the uncertainty evaluation of the second order Zeeman frequency shift. Microwave excitation method can be used to measure the average value of the time-weighted magnetic induction intensity at each height of the C field. In order to obtain the actual magnetic field distribution of C field, the measurement results of microwave excitation method need to be de-weighted. To introduces two de-time-weighted algorithms and verifies them with simulation data. Finally, the C field of NIM6 cesium fountain clock is measured and calculated by microwave excitation method and two de-time-weighted algorithms combined with Monte Carlo uncertainty evaluation method.
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2023, Vol. 44 
