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Auteur Pacôme Delva
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SYRTE - Systèmes de Référence Temps Espace
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Affiner la recherche Interroger des sources externesGENESIS: co-location of geodetic techniques in space / Pacôme Delva in Earth, Planets and Space, vol 75 n° 1 (2023)
Titre : GENESIS: co-location of geodetic techniques in space Type de document : Article/Communication Auteurs : Pacôme Delva, Auteur ; Zuheir Altamimi Année de publication : 2023 Article en page(s) : n° 5 (2023) Note générale : bibliographie
by Pacôme Delva, Zuheir Altamimi, Alejandro Blazquez, Mathis Blossfeld, Johannes Böhm, Pascal Bonnefond, Jean-Paul Boy, Sean Bruinsma, Grzegorz Bury, Miltiadis Chatzinikos, Alexandre Couhert, Clément Courde, Rolf Dach, Véronique Dehant, Simone Dell’Agnello, Gunnar Elgered, Werner Enderle, Pierre Exertier, Susanne Glaser, Rüdiger Haas, Wen Huang, Urs Hugentobler, Adrian Jäggi, Ozgur Karatekin, Frank G. Lemoine, Christophe Le Poncin-Lafitte, Susanne Lunz, Benjamin Männel, Flavien Mercier, Laurent Métivier, Benoît Meyssignac, Jürgen Müller, Axel Nothnagel, Felix Perosanz, Roelof Rietbroek, Markus Rothacher, Harald Schuh, Hakan Sert, Krzysztof Sosnica, Paride Testani, Javier Ventura-Traveset, Gilles Wautelet & Radoslaw ZajdelLangues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux
[Termes IGN] co-positionnement
[Termes IGN] géodésie spatiale
[Termes IGN] International Terrestrial Reference Frame
[Termes IGN] précision du positionnement
[Termes IGN] satellite de positionnementRésumé : (auteur) Improving and homogenizing time and space reference systems on Earth and, more specifically, realizing the Terrestrial Reference Frame (TRF) with an accuracy of 1 mm and a long-term stability of 0.1 mm/year are relevant for many scientific and societal endeavors. The knowledge of the TRF is fundamental for Earth and navigation sciences. For instance, quantifying sea level change strongly depends on an accurate determination of the geocenter motion but also of the positions of continental and island reference stations, such as those located at tide gauges, as well as the ground stations of tracking networks. Also, numerous applications in geophysics require absolute millimeter precision from the reference frame, as for example monitoring tectonic motion or crustal deformation, contributing to a better understanding of natural hazards. The TRF accuracy to be achieved represents the consensus of various authorities, including the International Association of Geodesy (IAG), which has enunciated geodesy requirements for Earth sciences. Moreover, the United Nations Resolution 69/266 states that the full societal benefits in developing satellite missions for positioning and Remote Sensing of the Earth are realized only if they are referenced to a common global geodetic reference frame at the national, regional and global levels. Today we are still far from these ambitious accuracy and stability goals for the realization of the TRF. However, a combination and co-location of all four space geodetic techniques on one satellite platform can significantly contribute to achieving these goals. This is the purpose of the GENESIS mission, a component of the FutureNAV program of the European Space Agency. The GENESIS platform will be a dynamic space geodetic observatory carrying all the geodetic instruments referenced to one another through carefully calibrated space ties. The co-location of the techniques in space will solve the inconsistencies and biases between the different geodetic techniques in order to reach the TRF accuracy and stability goals endorsed by the various international authorities and the scientific community. The purpose of this paper is to review the state-of-the-art and explain the benefits of the GENESIS mission in Earth sciences, navigation sciences and metrology. This paper has been written and supported by a large community of scientists from many countries and working in several different fields of science, ranging from geophysics and geodesy to time and frequency metrology, navigation and positioning. As it is explained throughout this paper, there is a very high scientific consensus that the GENESIS mission would deliver exemplary science and societal benefits across a multidisciplinary range of Navigation and Earth sciences applications, constituting a global infrastructure that is internationally agreed to be strongly desirable. Numéro de notice : A2023-078 Affiliation des auteurs : UMR IPGP-Géod+Ext (2020- ) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1186/s40623-022-01752-w Date de publication en ligne : 11/01/2023 En ligne : https://doi.org/10.1186/s40623-022-01752-w Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102519
in Earth, Planets and Space > vol 75 n° 1 (2023) . - n° 5 (2023)[article]
Titre : GENESIS: Co-location of Geodetic Techniques in Space Type de document : Article/Communication Auteurs : Pacôme Delva, Auteur ; Zuheir Altamimi Editeur : Ithaca [New York - Etats-Unis] : ArXiv - Université Cornell Année de publication : 2022 Projets : 1-Pas de projet / Note générale : bibliographie
auteurs : Pacome Delva, Zuheir Altamimi, Alejandro Blazquez, Mathis Blossfeld, Johannes Böhm, Pascal Bonnefond, Jean-Paul Boy, Sean Bruinsma, Grzegorz Bury, Miltiadis Chatzinikos, Alexandre Couhert, Clement Courde, Rolf Dach, Veronique Dehant, Simone Dell’Agnello, Gunnar Elgered, Werner Enderle, Pierre Exertier, Susanne Glaser, Rudiger Haas, Wen Huang, Urs Hugentobler17, Adrian J¨aggi11, Ozgur Karatekin12, Frank G. Lemoine18, Christophe Le Poncin-Lafitte, Susanne Lunz, Benjamin Mannel, Flavien Mercier, Laurent Metivier, Benoıt Meyssignac, Jurgen Muller, Axel Nothnage, Felix Perosanz, Roelof Rietbroek, Markus Rothacher, Hakan Sert, Krzysztof Sosnica, Paride Testani, Javier Ventura-Traveset, Gilles
Wautelet, and Radoslaw ZajdeLangues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux
[Termes IGN] co-positionnement
[Termes IGN] état de l'art
[Termes IGN] International Terrestrial Reference Frame
[Termes IGN] mission spatiale
[Termes IGN] station de mesureRésumé : (auteur) Improving and homogenizing time and space reference systems on Earth and, more directly, realizing the Terrestrial Reference Frame (TRF) with an accuracy of 1mm and a long-term stability of 0.1mm/year are relevant for many scientific and societal endeavors. The knowledge of the TRF is fundamental for Earth and navigation sciences. For instance, quantifying sea level change strongly depends on an accurate determination of the geocenter motion but also of the positions of continental and island reference stations, as well as the ground stations of tracking networks. Also, numerous applications in geophysics require absolute millimeter precision from the reference frame, as for example monitoring tectonic motion or crustal deformation for predicting natural hazards. The TRF accuracy to be achieved represents the consensus of various authorities which has enunciated geodesy requirements for Earth sciences.
Today we are still far from these ambitious accuracy and stability goals for the realization of the TRF. However, a combination and co-location of all four space geodetic techniques on one satellite platform can significantly contribute to achieving these goals. This is the purpose of the GENESIS mission, proposed as a component of the FutureNAV program of the European Space Agency. The GENESIS platform will be a dynamic space geodetic observatory carrying all the geodetic instruments referenced to one another through carefully calibrated space ties. The co-location of the techniques in space will solve the inconsistencies and biases between the different geodetic techniques in order to reach the TRF accuracy and stability goals endorsed by the various international authorities and the scientific community. The purpose of this white paper is to review the state-of-the-art and explain the benefits of the GENESIS mission in Earth sciences, navigation sciences and metrology.Numéro de notice : P2022-007 Affiliation des auteurs : UMR IPGP-Géod+Ext (2020- ) Thématique : POSITIONNEMENT Nature : Preprint nature-HAL : Préprint DOI : 10.48550/arXiv.2209.15298 Date de publication en ligne : 30/09/2022 En ligne : https://doi.org/10.48550/arXiv.2209.15298 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=101792
Titre : Towards a transportable Yb lattice clock at SYRTE Type de document : Article/Communication Auteurs : Wilfreddy Moreno, Auteur ; Fatima Rahmouni, Auteur ; Benjamin Pointard, Auteur ; Paul-Eric Pottie, Auteur ; Pacôme Delva, Auteur ; Jérôme Lodewyck, Auteur ; Rodolphe Letargat, Auteur ; J. Romero González, Auteur ; M.-F. Lalancette, Auteur ; Guillaume Lion Editeur : New York : Institute of Electrical and Electronics Engineers IEEE Année de publication : 2022 Projets : ROYMAGE / Letargat, Rodolphe Conférence : EFTF-IFCS 2022, Joint Conference of the European Frequency and Time Forum and IEEE International Frequency Control Symposium 24/04/2022 28/04/2022 Paris France Proceedings IEEE Note générale : bibliographie
This work has received support from Agence Nationale de la Recherche (ANR) with project ROYMAGE (ANR-20-CE47-0006), DIM SIRTEQ and Labex First-TF with project PATHYNAGE, Scientific Council of Observatoire de Paris with project LARYNGITE, and the European Metrology Program for Innovation and Research (EMPIR), with project 18SIB05 ROCIT.
présenté aussi sous "Towards a high flux transportable Ytterbium Optical lattice Clock" aux Houches School of Physics, Cold Atom Predoc School Quantum mixtures, 26 sept-7 oct 2022Langues : Français (fre) Descripteur : [Vedettes matières IGN] Métrologie
[Termes IGN] chronométrie
[Termes IGN] fréquence
[Termes IGN] horloge optique
[Termes IGN] horlogerieRésumé : (auteur) We describe the design of a transportable optical lattice clock based on neutral ytterbium at SYRTE, Observatoire de Paris. This instrument will be connected to the network of ultrastable fiber links REFIMEVE+ with the objective of contributing both to Earth sciences and to frequency metrology. Note de contenu : 2022 Joint Conference of the European Frequency and Time Forum and IEEE International Frequency Control Symposium (EFTF/IFCS) Numéro de notice : C2022-034 Affiliation des auteurs : UMR IPGP-Géod+Ext (2020- ) Autre URL associée : vers HAL Thématique : POSITIONNEMENT Nature : Communication nature-HAL : Poster-avec-CL DOI : 10.1109/EFTF/IFCS54560.2022.9850674 Date de publication en ligne : 15/08/2022 En ligne : https://doi.org/10.1109/EFTF/IFCS54560.2022.9850674 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=101381
Titre : Optimization of optical clock network for the geopotential determination Type de document : Article/Communication Auteurs : Guillaume Lion Editeur : Saint-Mandé : Institut national de l'information géographique et forestière - IGN (2012-) Année de publication : 2019 Conférence : AGU 2019 Fall Meeting 09/12/2019 13/12/2019 San Francisco Californie - Etats-Unis programme sans actes Projets : ChronoG2o / Letargat, Rodolphe Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] chronométrie
[Termes IGN] décalage d'horloge
[Termes IGN] horloge optique
[Termes IGN] optimisation (mathématiques)
[Termes IGN] potentiel de pesanteur terrestreRésumé : (auteur) Clock comparisons with an uncertainty at the 10−18 in terms of relative frequency can provide a new kind of measurement to improve our knowledge of Earth’s gravity field and geoid. Instead of using state-of-the-art Earth’s gravitational field models to predict frequency shifts between distant clocks, they could permit determining geopotential differences at a centimeter-level accuracy, and question the possibility of studying geodynamic processes leading to very small vertical deformations or improve the unification of height systems. In our previous work dealing with the geopotential determination at high spatial resolution in mountainous regions, we have pointed out that clock-based geodetic observable can provide useful information at spatial scales beyond what is available from satellites and they could be used to fill areas not covered by the gravity data on the ground. Our synthetic simulations have shown that adding few clock-based potential data to a gravimetric data set can significantly improve the reconstruction of the geopotential. Therefore, it turns out there is a large variety of possible clock distribution allowing to reduce the reconstruction residuals, with different locations and number of clocks. In this work, we investigate ways to optimize clock network from a gravimetric data set in the Massif Central region in order to know where to put them to minimize the residuals and improve further the determination of the geopotential. To do that, we have used a multi-objective genetic algorithm (GA). Starting from a random initial population with different clock distributions, the algorithm selects clock locations with good chances of reproduction and reproduces the new generation of clock locations using genetic operators. The process depends on some objectives we want to reach in order to solve the optimization problem, and it is repeated several times for a given number of generations or until a solution considered as optimum is found. We show how GA can help to provide optimal solutions for a problem with a fixed and variable number of clock locations. We discuss the effect of different parameters, such as the way to define the objectives and the constrains of the problem, the quality of the clock network and the data. Numéro de notice : C2019-057 Affiliation des auteurs : Géodésie+Ext (mi2018-2019) Thématique : POSITIONNEMENT Nature : Poster nature-HAL : Poster-avec-CL DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96833
Titre de série : Relativistic geodesy, ch. 2 Titre : Chronometric geodesy: Methods and applications Type de document : Chapitre/Contribution Auteurs : Pacôme Delva, Auteur ; Heiner Denker, Auteur ; Guillaume Lion Editeur : Springer International Publishing Année de publication : 2019 Collection : Fundamental Theories of Physics num. 196 Projets : ITOC / Letargat, Rodolphe, AdOC / Letargat, Rodolphe, FIRST-TF / Letargat, Rodolphe Importance : pp 25 - 85 Note générale : bibliographie
This research was supported by the European Metrology Research Programme (EMRP) within the Joint Research Project “International Timescales with Optical Clocks” (SIB55 ITOC), as well as the Deutsche Forschungsgemeinschaft (DFG) within the Collaborative Research Centre 1128 “Relativistic Geodesy and Gravimetry with Quantum Sensors (geo-Q)”, project C04. The EMRP is jointly funded by the EMRP participating countries within EURAMET and the European Union. We gratefully acknowledge financial support from Labex FIRST-TF and ERC AdOC (Grant No. 617553).Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] champ de pesanteur terrestre
[Termes IGN] chronométrie
[Termes IGN] décalage d'horloge
[Termes IGN] échelle de temps
[Termes IGN] horloge atomiqueRésumé : (auteur) The theory of general relativity was born more than one hundred years ago, and since the beginning has striking prediction success. The gravitational redshift effect discovered by Einstein must be taken into account when comparing the frequencies of distant clocks. However, instead of using our knowledge of the Earth’s gravitational field to predict frequency shifts between distant clocks, one can revert the problem and ask if the measurement of frequency shifts between distant clocks can improve our knowledge of the gravitational field. This is known as chronometric geodesy. Since the beginning of the atomic time era in 1955, the accuracy and stability of atomic clocks were constantly ameliorated, with around one order of magnitude gained every ten years. Now that the atomic clock accuracy reaches the low 10−18 in fractional frequency, and can be compared to this level over continental distances with optical fibres, the accuracy of chronometric geodesy reaches the cm level and begins to be competitive with classical geodetic techniques such as geometric levelling and GNSS/geoid levelling. Moreover, the building of global timescales requires now to take into account these effects to the best possible accuracy. In this chapter we explain how atomic clock comparisons and the building of timescales can benefit from the latest developments in physical geodesy for the modelization and realization of the geoid, as well as how classical geodesy could benefit from this new type of observable, which are clock comparisons that are directly linked to gravity potential differences. Numéro de notice : H2019-006 Affiliation des auteurs : Géodésie+Ext (mi2018-2019) Thématique : POSITIONNEMENT Nature : Chapître / contribution nature-HAL : ChOuvrScient DOI : 10.1007/978-3-030-11500-5_2 Date de publication en ligne : 10/02/2019 En ligne : https://doi.org/10.1007/978-3-030-11500-5_2 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95546 
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