On the calibration of a superconducting gravimeter using absolute gravity measurements

Jacques Hinderer (1) , Nicolas Florsch (2) , J. Mäkinen (3) , Hilaire Legros (1) , J. E. Faller (4)

1 IPGS - Institut de physique du globe de Strasbourg
2 Laboratoire de Géophysique appliquée
3 Finnish Geodesic Institute
4 JILA - Joint Institute for Laboratory Astrophysics

A 24 hr continuous parallel registration between an absolute free-fall gravimeter and a relative cryogenic gravimeter is analysed. Different adjustment procedures (L,, L2 norms) are applied to the sets of absolute and relative readings in order to estimate the value of the calibration factor of the superconducting meter, as well as its uncertainty. In addition, a sensitivity test is performed to investigate the influence of some parameters (like the laser frequency and its short-term drift) upon this factor. The precision in the calibration factor is found to be better than 1 per cent, but systematic effects related to the short time interval may add another one and half per cent uncertainty. From preliminary results, it appears that this calibration experiment leads to a close agreement between the values of the gravimetric factor for the reference tidal wave O1 observed with the superconducting meter and the theoretical value (Dehant-Wahr body tide + ocean loading).

Mots clés: absolute gravity; calibration; superconducting gravimeter

Domaines: Sciences de l'environnement

Jacques Hinderer, Nicolas Florsch, J. Mäkinen, Hilaire Legros, J. E. Faller. On the calibration of a superconducting gravimeter using absolute gravity measurements. Geophysical Journal International, 1991, 106, p. 491-497. ⟨10.1029/98GL00712⟩. ⟨hal-00958578⟩