Rosat S. auteur aut IRD Florsch Nicolas auteur aut IRD Hinderer J. auteur aut IRD Llubes M. auteur aut IRD text journalArticle eng text/pdf born digital access The Free Core Nutation (FCN) is investigated with the help of its resonance effect on the tidal amplitudes in Superconducting Gravimeter (SG) records of the GGP network. The FCN resonance parameters are combined in a resonance equation involving the Earth's interior parameters. The sensitivity of the FCN parameters to the diurnal tidal waves demonstrates that the quality factor of the FCN is strongly dependent on the accuracy of the imaginary part estimates of the gravimetric factors close to the resonance. The weak amplitude of Psi(1) tidal wave on the Earth, which is the closest in frequency to the FCN, in addition to errors in ocean loading correction, explains the poor determination of the quality factor Q from surface gravimetric data. The inversion of tidal gravimetric factors leads to estimates of the period, Q and resonance strength of the FCN. We show that. by inverting log(Q) instead of Q the results using the least-squares method optimized using the Levenberg-Marquardt algorithm are in agreement with the Bayesian probabilistic results and agree with the results obtained from VLBI nutation data. Finally, a combined inversion of 7 GGP European SG data is performed giving T = 428 +/- 3 days and 7762 < Q < 31,989 (90% C.I.). An experimental estimate of the internal pressure Love number is also proposed. specialized Free Core Nutation Superconducting Gravimeter Bayesian analysis 032 020 48 3-5 331-339 2009 0264-3707 https://www.documentation.ird.fr/hor/fdi:010048519 10.1016/j.jog.2009.09.027 0264-3707 [F B010048519] https://www.documentation.ird.fr/hor/fdi:010048519 https://www.documentation.ird.fr/intranet/publi/2010/01/010048519.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2010-02-08 2017-08-23 fdi:010048519 fre