Evaluation of the Exail absolute quantum gravimeters AQG-A02 and AQG-B10 by comparison to a precise gravity reference

We present an evaluation of the novel absolute quantum gravimeters AQG-A02 and AQG-B10 by the French manufacturer Exail with an emphasis on the user's application and outlook for integration into the routine gravity measurements of the German Federal Agency for Cartography and Geodesy (BKG). Since the delivery of these instruments to BKG, test measurements have been performed at the well-established gravity reference stations in Wettzell and Bad Homburg. Our measurements confirm a sensitivity of 500 nm s⁻² Hz^−1/2 at a quiet site, as specified, equivalent to a precision of 10 nm/s² after 1-h integration time, and a combined uncertainty on the order of 100 nm/s², based on a comparison to the local gravity reference function. We conclude that, as of yet, both AQGs do not reach the accuracy of FG5-type gravimeters, but provide advantages for continuous measurements and operation. Despite occasional technical issues with system reliability and pending research on improving the systematic errors, we expect the AQGs will find a central role in BKG's routine gravity measurements in the near future.