27 October 2022
Absolute gravimeters play a key role in the National Research Infrastructure sensor network Resif. In particular, they are used to make repeated absolute measurements on the RésRéf reference network and to measure the scale factors and drift of the superconducting relative gravimeters, which measure gravity variations continuously over the national territory. This set of measurements constitutes a part of the activities of the Service National d’Observation (SNO) Gravimétrie.
The National Instrumental Park (PIN) PGrav, managed by the Gravimetry Specific Action of the national research infrastructure Resif-EPOS, has five absolute gravimeters: two Micro-g Lacoste FG5, two Muquans-iXblue AQG and the national metrological reference CAG, which is also a quantum gravimeter, developed by the IACI team at SYRTE.
The Atomic Interferometry and Inertial Sensors (IACI) team at SYRTE is currently hosting a comparison of absolute gravimeters.
This comparison challenges several objectives, as it allows to :
check the agreement between absolute instruments and thus the consistency of their measurements and the resulting products,
check the scale factor of the continuous monitoring gravimeter of the comparison site usually evaluated by the atomic gravimeter CAG of LNE-SYRTE, currently under renovation,
quantitatively evaluate the improvements brought to the AQG of the park, as for their performances but also their facility of implementation and use to be able to propose them more easily to the users of the network.
At the end of the first week of comparison, other national instruments will be involved in a session to evaluate the long-term performance of the AQGs.
The instruments participating in the comparison are operated by EOST, Géosciences Montpellier, iXBlue-MuQuans, GET, IRD, l’IPGP, IGN, SHOM and LNE-SYRTE.
Researcher contact:
Sébastien Merlet
For more information:
The team’s page on gravimetry activities:
https://syrte.obspm.fr/spip/science/iaci/projets-en-cours/gravimetre/
News on the RESIF network website:
https://www.resif.fr/blog/2022/10/24/comparaison-des-gravimetres-absolus-du-pin-pgrav/