Toward Reliable Estimates of the Free Core and Inner Core Parameters from a Bayesian Inversion of VLBI and Gravimetric Data

International audience During the last decades, many authors have provided their own estimates of the FCN parameters. Some of them have also tried to detect and characterize the FICN. The agreement between all of these studies is far from satisfying, however, whatever data set is used, either VLBI o...

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Bibliographic Details
Main Authors: Ziegler, Yann, Lambert, Sébastien, Rosat, S., Bizouard, Christian
Other Authors: Observatoire de Paris, Université Paris sciences et lettres (PSL)
Format: Conference Object
Language:English
Published: HAL CCSD 2018
Subjects:
Online Access:https://hal.archives-ouvertes.fr/hal-03804453
Description
Summary:International audience During the last decades, many authors have provided their own estimates of the FCN parameters. Some of them have also tried to detect and characterize the FICN. The agreement between all of these studies is far from satisfying, however, whatever data set is used, either VLBI or gravimetric data. Before providing another set of estimates from a joint Bayesian inversion of data from both aforementioned techniques, we endeavor in the present work to quantify the accuracy with which the FCN and FICN could be determined, considering the available data and the likely errors that distort them. Our synthetic tests suggest that if the FCN period and quality factor could be estimated with uncertainties smaller than one day and 10% respectively, the FICN is still much more difficult to characterize, assuming it can be routinely detected at all.