The absolute gravimeter is based on atom interferometry techniques applied to cold atoms.
Gravimeter
In the frame of the Kibble balance project of the Laboratoire National de Métrologie et d’Essais (LNE), the LNE-SYRTE is developing an absolute gravimeter. This experiment will allow realizing an accurate measurement of gravity acceleration g in the vicinity of the balance, with a 10-9 relative uncertainty. Moreover, in order to reduce the uncertainty in the transfer of g between the locations of the gravimeter and of the test mass in the balance, we realize the gravimetric characterization of the LNE laboratories at Trappes, suburb of Paris. These activities led naturally SYRTE to be part of the National Service of Observation in Gravimetry
- Gravimetry laboratory
- The picture was taken during a comparison campaign of absolute gravimeters, where the CAG and two Muquans gravimeters, belonging to the Epos-France (ex RESIF) network and to the Observatoire Midi-Pyrénées (Courtesy of LNE)
The gravimetry laboratory is located at the LNE premises, in the electrical metrology laboratories, next to the Kibble balance
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Cold atom gravimeter
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Gravimetry
In the frame of the Kibble balance project (previously Watt balance), g has to be determined at the center of mass of the involved mass. It is then necessary to transfer the g absolute value obtain with the atom gravimeter to the location of this mass. For that purpose, we characterize the gravity variations in the two neighboring rooms in which the two experiments are located.
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SNO Gravimetry
The continuous signals of the superconducting relative gravimeter iGrav005, followed by the absolute atomic gravimeter, are made available to the community through participation in the Service National d’Observation (SNO) Gravimetry