First results from the AQG-B07 absolute quantum gravimeter

In October of 2021 the AQG-B07 absolute quantum gravimeter has been installed at the Borowa Góra Geodetic Geophysical Observatory. Since its installation the instrument is under ongoing evaluation performance and testing at Borowa Góra as well as in other locations in Poland.

Within the first months of the AQG-B07 operation periodic continuous measurements were conducted at Borowa Góra as well as multiple gravity determinations on gravity stations at the gravimetric laboratory. Gravity values obtained with the AQG-B07 were compared with those from the A10-020 absolute gravimeter using the record of the iGrav-027 superconducting gravimeter to evaluate the offset between those absolute instruments. Continuous gravity records allowed to evaluate the short term stability of the AQG-B07 against the expected behaviour of the instrument. By the end of 2021 a 12 day record have been collected with a broadband seismometer recording side by side which allowed to evaluate the noise characteristic of residual gravity values collected with the AQG-B07 gravimeter.

In January of 2022 the gravimeter was operating in Warsaw in the premises of the Institute of Geodesy and Cartography located in an urban area. Gravity measurements conducted in more active micro seismic environment allowed to gain a better perspective on the performance of the AQG-B07. Absolute gravity determinations were simultaneously done with the A10-020 gravimeter at the same location.

Evaluations of noise as well as analysis against the seismometer, in particular to test the ability of the AQG-B07 to record earthquakes for determination of the seismic structure of the Earth's mantle from the analysis of surface waveforms, were performed in the framework of the research project No. 2017/27/B/ST10/01600 financed from the funds of the Polish National Science Centre.