Détail de l'auteur
Auteur Bernard Foulon |
Documents disponibles écrits par cet auteur (3)
Ajouter le résultat dans votre panier Affiner la recherche Interroger des sources externes
Space test of the Equivalence Principle: first results of the MICROSCOPE mission / Pierre Touboul in Classical and Quantum Gravity, vol 36 n° 22 (November 2019)
[article]
Titre : Space test of the Equivalence Principle: first results of the MICROSCOPE mission Type de document : Article/Communication Auteurs : Pierre Touboul, Auteur ; Gilles Métris, Auteur ; Manuel Rodrigues, Auteur ; Quentin Baghi, Auteur ; Joel Bergé, Auteur ; Damien Boulanger, Auteur ; Stefanie Bremer, Auteur ; Ratana Chhun, Auteur ; Bruno Christophe, Auteur ; Valerio Cipolla, Auteur ; Thibault Damour, Auteur ; Pascal Danto, Auteur ; Hansjoerg Dittus, Auteur ; Pierre Fayet, Auteur ; Bernard Foulon, Auteur ; Pierre-Yves Guidotti, Auteur ; Emilie Hardy, Auteur ; Phuong-Anh Huynh, Auteur ; Claus Lämmerzahl, Auteur ; Vincent Lebat, Auteur ; Françoise Liorzou, Auteur ; Meike List, Auteur ; Isabelle Panet , Auteur ; et al., Auteur Année de publication : 2019 Projets : 1-Pas de projet / Article en page(s) : n° 225006 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Missions spatiales
[Termes IGN] MICROSCOPE (mission)
[Termes IGN] principe d'équivalenceRésumé : (auteur) The weak equivalence principle (WEP), stating that two bodies of different compositions and/or mass fall at the same rate in a gravitational field (universality of free fall), is at the very foundation of general relativity. The MICROSCOPE mission aims to test its validity to a precision of 10−15, two orders of magnitude better than current on-ground tests, by using two masses of different compositions (titanium and platinum alloys) on a quasi-circular trajectory around the Earth. This is realised by measuring the accelerations inferred from the forces required to maintain the two masses exactly in the same orbit. Any significant difference between the measured accelerations, occurring at a defined frequency, would correspond to the detection of a violation of the WEP, or to the discovery of a tiny new type of force added to gravity. MICROSCOPE's first results show no hint for such a difference, expressed in terms of Eötvös parameter (both 1 uncertainties) for a titanium and platinum pair of materials. This result was obtained on a session with 120 orbital revolutions representing 7% of the current available data acquired during the whole mission. The quadratic combination of 1 uncertainties leads to a current limit on of about xxx. Numéro de notice : A2019-633 Affiliation des auteurs : Géodésie+Ext (mi2018-2019) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1088/1361-6382/ab4707 Date de publication en ligne : 18/10/2019 En ligne : https://doi.org/10.1088/1361-6382/ab4707 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95449
in Classical and Quantum Gravity > vol 36 n° 22 (November 2019) . - n° 225006[article]Ultra-sensitive electrostatic planar acceleration gradiometer for airborne geophysical surveys / Karim Douch in Measurement Science and Technology, vol 25 n° 10 (October 2014)
[article]
Titre : Ultra-sensitive electrostatic planar acceleration gradiometer for airborne geophysical surveys Type de document : Article/Communication Auteurs : Karim Douch , Auteur ; Bruno Christophe, Auteur ; Bernard Foulon, Auteur ; Isabelle Panet , Auteur ; Gwendoline Pajot-Métivier , Auteur ; Michel Diament , Auteur Année de publication : 2014 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] accéléromètre
[Termes IGN] gradiomètre
[Termes IGN] gravimétrie aérienne
[Termes IGN] instrument de géophysiqueRésumé : (auteur) We propose a new concept of gravity gradiometer, GREMLIT, for the determination of the spatial derivatives of gravitational acceleration during airborne surveys. The core of this instrument is the acceleration gradiometer composed of four ultra-sensitive electrostatic planar accelerometers, inheriting from technologies developed for the GRACE and GOCE satellite gravity missions. Data from these missions have greatly improved our knowledge of the Earth's gravity field and its time variations. However, resolving wavelengths of a few 10 km or less, beyond the reach of the satellite resolution, is of utmost importance to study a number of crustal geophysical processes and geological structures. We first present the benefits for a new gravity gradiometer, then we describe the planar acceleration gradiometer, which put together with three orthogonal gyroscopes, constitutes the gravity gradiometer GREMLIT. The acceleration gradiometer enables measurement at one point of the horizontal spatial derivatives of the acceleration horizontal components. We explain the measurement principle and describe the computation of the gravity gradients along with the necessary ancillary measurements. From a detailed error budget analysis of the accelerometers, an expected spectral sensitivity below $\text{1E/}\sqrt{\text{Hz}}$ is found in the [10−3, 0.2] Hz measurement bandwidth. To maintain such performance in flight, we finally discuss the adaptation of the acceleration gradiometer to the turbulent airborne environment. To limit the saturation of the accelerometers, we propose to cancel the common-mode output of the acceleration gradiometer by integrating the instrument on a double-gimbal platform controlled by the common-mode. We demonstrate on a real case study that with such a solution, it is technically possible to prevent the saturation of the accelerometers at least 95% of the time and it is not damaging to the airborne survey. Numéro de notice : A2014-782 Affiliation des auteurs : LASTIG LAREG+Ext (2012-mi2018) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1088/0957-0233/25/10/105902 Date de publication en ligne : 20/08/2014 En ligne : http://dx.doi.org/10.1088/0957-0233/25/10/105902 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=78599
in Measurement Science and Technology > vol 25 n° 10 (October 2014)[article]
Titre : A new planar electrostatic gravity gradiometer for airborne surveys Type de document : Article/Communication Auteurs : Karim Douch , Auteur ; Bernard Foulon, Auteur ; Bruno Christophe, Auteur ; Michel Diament , Auteur ; Gwendoline Pajot-Métivier , Auteur ; Isabelle Panet , Auteur Editeur : Tulsa [Oklahoma - Etats-Unis] : Society of Exploration Geophysicists SEG Année de publication : 2013 Conférence : SEG 2013, Society of Exploration Geophysicists International Exposition and 83rd Annual Meeting, Expanding Geophysical Frontiers 22/09/2013 27/09/2013 Houston Texas - Etats-Unis Proceedings Curran Associates Importance : pp 1216 - 1219 Note générale : in SEG Technical Program Expanded Abstracts 2013 Langues : Français (fre) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] gradiomètre
[Termes IGN] gravimètre
[Termes IGN] gravimétrie aérienne
[Termes IGN] instrument aéroporté
[Termes IGN] instrument de géodésieRésumé : (auteur) Compared to classical gravimetric surveys, the measurement of the spatial rates of the gravitational acceleration offers an improved insight on the distribution and geometry of the subsurface causative masses. Though, there is only one commercialized gradiometer system currently available on the market. The purpose of our project is thus to develop a new compact gravity gradiometer based on electrostatic accelerometers, for airborne or ship-borne surveys. These accelerometers inherit from technologies developed by ONERA for spatial missions like GRACE or GOCE. The principle of measurement is described along with a first assessment of its performance in real airborne conditions. The goal is to reach the critical precision of 1Eötvös corresponding to a sensitivity to variations of 0.1μGal/m. Numéro de notice : C2013-021 Affiliation des auteurs : LASTIG LAREG+Ext (2012-mi2018) Autre URL associée : lien DOI Thématique : POSITIONNEMENT Nature : Communication nature-HAL : ComAvecCL&ActesPubliésIntl DOI : 10.1190/segam2013-1122.1 En ligne : https://www.researchgate.net/profile/Bruno-Christophe/publication/269042781_A_ne [...] Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97261