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Relativistic geodesy, ch. 2. Chronometric geodesy: Methods and applications / Pacôme Delva (2019)  

Public 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 , Auteur Editeur : Springer International Publishing Année de publication : 2019 Collection : Fundamental Theories of Physics num. 196 Projets : ITOC / , AdOC / , FIRST-TF / 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 atomique Résumé : (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

Radial orbit error reduction and sea surface topography determination using one year of Geosat altimeter data / Heiner Denker (1990)

Public Titre : Radial orbit error reduction and sea surface topography determination using one year of Geosat altimeter data Type de document : Monographie Auteurs : Heiner Denker, Auteur Editeur : Colombus (Ohio) : Ohio State University Année de publication : 1990 Collection : Department of Geodetic Science and Surveying Reports num. 404 Importance : 63 p. Format : 21 x 27 cm Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] altimétrie [Termes IGN] image GeoSat [Termes IGN] orbite [Termes IGN] relief de la surface de la mer [Termes IGN] surface de la mer [Vedettes matières IGN] Altimétrie Index. décimale : 30.52 Marégraphie et niveau moyen des mers Numéro de notice : 12090 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Monographie Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=54520

Exemplaires(1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
12090-01	30.52	Livre	Centre de documentation	Géodésie	Disponible

Long range geoid control through the european GPS traverse / Wolfgang Torge (1989)

Public Titre : Long range geoid control through the european GPS traverse Type de document : Monographie Auteurs : Wolfgang Torge, Auteur ; Tomislav Basic, Auteur ; Heiner Denker, Auteur ; et al., Auteur Editeur : Munich : Bayerische Akademie der Wissenschaften Année de publication : 1989 Collection : DGK - B Sous-collection : Angewandte Geodäsie num. 290 Importance : 25 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-3-7696-8575-6 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique [Termes IGN] coordonnées ellipsoïdales [Termes IGN] Europe centrale [Termes IGN] Europe du nord [Termes IGN] géoïde local [Termes IGN] gravimétrie [Termes IGN] hauteur ellipsoïdale [Termes IGN] positionnement par GPS [Termes IGN] précision altimétrique [Termes IGN] réseau européen unifié de nivellement [Termes IGN] traverse géodésique Index. décimale : 30.41 Géoïde Résumé : (Auteur) The European north-south GPS traverse, proposed by IAG SSG 3.88, should control and improve the European geoid. This traverse follows first order leveling lines included in the United European Leveling Network (UELN). From May to August 1986 and in July 1987, the central and northern part of this traverse (approx. 3000 km) was observed in cooperation with several European geodetic institutions using up to four TI 4100 receivers covering Austria, Federal Republic of Germany, Denmark, Sweden and Norway. Both traverse parts contain 71 stations with distances of about 50 km. In addition, 8 stations were occupied for overlapping connections, and traverse links were established for connecting the fundamental stations Wettzell (VLBI and SLR) and Onsala (VLBI). The reconnaissance of the GPS stations and local connecting measurements were performed mainly by the responsible State Survey Agencies. The Statens Kartverk (Norway), The Royal Institute of Technology, Stockholm (Sweden), the Lantmateriet (Sweden) and the Institut für Astronomische und Physikalische Geodäsie, TU München, participated active with own TI 4100 receivers. Final results show a GPS observation precision of a few cm for loops of some 100 km circumference. After transformation of the GPS results to geoïd heights using the leveled heights, comparisons with different existing gravimetric geoïd determinations including geopotential models have been performed. In addition, new geopotential models complete to degree and order 360 tailored to gravity data in Europe and gravimetric geoïd solutions using 6'x10' mean gravity anomalies have been investigated. The comparison with GPS and leveling yields rms discrepancies of ±0.1... 0.2 m over 1000 km traverse sections for the best solutions, but a strong slope is existing in Sweden and southern Norway in almost all solutions, which is probably caused by systematic errors in, the available gravity data for Scandinavia. This is confirmed by a tailored model using an updated gravity data set for Scandinavia and by a new geoïd computation at the Danish Geodetic Institute, where the slope has disappeared. If this new solution from the Danish Geodetic Institute is taken for the northern traverse section and our best solution for the central part, the rms discrepancy reduces to approx. ±0.2 m over 3000 km. Thus, a ±10-7 relative height accuracy seems to be achievable over long distances with the GPS/leveling and the gravimetric geoïd calculation techniques applied in this experiment. Numéro de notice : 38854 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Monographie Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=57613

Exemplaires(2)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
38854-01	30.41	Livre	Centre de documentation	Géodésie	Disponible
38854-02	30.41	Livre	Centre de documentation	Géodésie	Disponible

A new gravimetric quasigeoid for the Federal Republic of Germany / Heiner Denker (1989)

Public Titre : A new gravimetric quasigeoid for the Federal Republic of Germany Type de document : Monographie Auteurs : Heiner Denker, Auteur Editeur : Munich : Bayerische Akademie der Wissenschaften Année de publication : 1989 Collection : DGK - B Sous-collection : Angewandte Geodäsie num. 291 Importance : 40 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-3-7696-8576-3 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique [Termes IGN] base de données topographiques [Termes IGN] géoïde gravimétrique [Termes IGN] géoïde local [Termes IGN] harmonique sphérique [Termes IGN] levé gravimétrique [Termes IGN] modèle de géopotentiel [Termes IGN] pesanteur terrestre [Termes IGN] République fédérale d'Allemagne [Termes IGN] transformation rapide de Fourier Index. décimale : 30.41 Géoïde Résumé : (Auteur) In this report, the computation method, the used data and practical results of a new high resolution gravimetric geoid determination for the area of the Federal Republic of Germany are described. The combination of point and mean gravity data as well as topographic informations with a global geopotential model is performed by means of integral formulas evaluated by Fast Fourier Transforms (FFT). The effect of the topography and a spherical harmonic model are taken into account in a so-called remove-restore technique. The result is represented by 80208 height anomalies stored in a file for a grid with mesh size 60"x100", from which height anomalies and deflections of the vertical can be interpolated to stations with given geodetic latitude and longitude using the Fortran subroutine GEOFRG. The subroutine GEOFRG and the corresponding grid file is obtainable from Institut für Erdmessung, Universität Hannover, on 9-track magnetic tape or on MS-DOS diskette. Numéro de notice : 38740 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Monographie Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=57609

Exemplaires(2)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
38740-01	30.41	Livre	Centre de documentation	Géodésie	Disponible
38740-02	30.41	Livre	Centre de documentation	Géodésie	Disponible