Investigation on gPhone gravimeter-119 for gravity variations observation during the 10th International Comparison of Absolute Gravimeters (ICAG-2017)

摘要

The 10th International Comparison of Absolute Gravimeters (ICAG-2017) was held in Changping campus of NationalInstitute of Metrology (NIM), China in October 2017. The observation of gravity variations using relative gravimetersplays an important role in absolute gravimeter comparison and the link of gravity reference value after comparison. Wecarried out a continuous observation of gPhone gravimeter-119 simultaneously alongside a superconductive gravimeteriGrav-012 for several months. The calibration factor of gPhone-119 is determined to be 0.99355±0.00004 with aprecision of 0.004%. When the observation time exceeds 33000 minutes, the calibration values and uncertainties tend tobe stable and the precision is better than 0.01%. The non-tidal gravity changes during ICAG-2017 recorded bygPhone-119 are analyzed. The tendency of gravity variations is roughly consistent with that recorded by iGrav-012. Theresult indicates that the peak-to-peak value of gravity changes is less than 1.5 μGal during the period of ICAG-2017.