First results from an absolute atom interferometry gravimeter at Mt. Etna volcano

In the framework of the NEWTON-g project, the field version of the Absolute Quantum Gravimeter produced by iXblue (AQG-B) was deployed in the summit crater zone of Mt. Etna volcano (Italy), in the summer of 2020. This is the first absolute atom interferometry gravimeter ever deployed on an active volcano. The device was installed in the facilities of the Pizzi Deneri volcanological observatory (PDN; 2800 m elevation, 2.5 km from the summit craters).
Despite the unfavorable environmental conditions at the installation site and the occurrence of phases of high volcanic tremor, the AQG-B provided high-quality continuous data, suitable for studying volcano-related gravity changes. Indeed, it has been possible to track gravity changes with amplitudes ranging between a few tens and a few hundreds of nm/s², occurring over a wide range of time scales.
Here, we describe the main features of the AQG-B and the issues that were addressed to allow its deployment in the summit zone of an active volcano. We also present the months-long time series that were acquired in 2020 and 2021, with a special focus on the anomalies likely related to volcanic processes.