Abstract:Vector atomic magnetometers for deep space magnetic field detection applications not only need to have high sensitivity in weak fields, but also need to have long-term accurate measurement capabilities. Therefore, it is necessary to test and calibrate the sensitivity and linearity of the vector atomic magnetometer in the near zero field, especially the performance of accuracy. At present, there is no device that can directly test and calibrate the magnetometer under weak magnetic field in the national standard measurement mechanism. An indirect test and calibration device and method under near zero field is proposed. In the magnetic shielding cylinder, the magnetic field generating coil is calibrated by the calibrated CPT atomic magnetometer. The calibrated coil generates a weak artificial magnetic field. Combined with the zero-point rotation test calibration method, the accuracy of the magnetometer is calibrated. The test calibration and uncertainty analysis of the near zero-field high precision atomic magnetometer sensor were completed. The linearity within the ±5nT range is 0.03%, the zero-point uncertainty is 12.90pT (1σ), and the accuracy is 15.80pT (1σ).