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979 results on '"CEA/DAM"'

1. Identification of a millisecond isomeric state in Cd81129 via the detection of internal conversion and Compton electrons

Author

Taprogge, J.(Instituto de Estructura de la Materia, CSIC, Madrid, E-28006, Spain), Jungclaus, A.(Instituto de Estructura de la Materia, CSIC, Madrid, E-28006, Spain), Grawe, H.(GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt, 64291, Germany), Nishimura, S.(RIKEN Nishina Center, RIKEN, 2-1 Hirosawa, Wako-shi, Saitama, 351-0198, Japan), Xu, Z.Y.(RIKEN Nishina Center, RIKEN, 2-1 Hirosawa, Wako-shi, Saitama, 351-0198, Japan), Doornenbal, P.(RIKEN Nishina Center, RIKEN, 2-1 Hirosawa, Wako-shi, Saitama, 351-0198, Japan), Lorusso, G.(RIKEN Nishina Center, RIKEN, 2-1 Hirosawa, Wako-shi, Saitama, 351-0198, Japan), Nácher, E.(Instituto de Estructura de la Materia, CSIC, Madrid, E-28006, Spain), Simpson, G.S.(LPSC, Université Joseph Fourier Grenoble 1, CNRS/IN2P3, Institut National Polytechnique de Grenoble, Grenoble cedex, F-38026, France), Söderström, P.-A.(RIKEN Nishina Center, RIKEN, 2-1 Hirosawa, Wako-shi, Saitama, 351-0198, Japan), Sumikama, T.(Department of Physics, Tohoku University, Aoba, Sendai, Miyagi, 980-8578, Japan), Baba, H.(RIKEN Nishina Center, RIKEN, 2-1 Hirosawa, Wako-shi, Saitama, 351-0198, Japan), Browne, F.(School of Computing, Engineering and Mathematics, University of Brighton, Brighton, BN2 4JG, United Kingdom), Fukuda, N.(RIKEN Nishina Center, RIKEN, 2-1 Hirosawa, Wako-shi, Saitama, 351-0198, Japan), Gernhäuser, R.(Physik Department E12, Technische Universität München, Garching, D-85748, Germany), Gey, G.(LPSC, Université Joseph Fourier Grenoble 1, CNRS/IN2P3, Institut National Polytechnique de Grenoble, Grenoble cedex, F-38026, France), Inabe, N.(RIKEN Nishina Center, RIKEN, 2-1 Hirosawa, Wako-shi, Saitama, 351-0198, Japan), Isobe, T.(RIKEN Nishina Center, RIKEN, 2-1 Hirosawa, Wako-shi, Saitama, 351-0198, Japan), Jung, H.S.(Department of Physics, Chung-Ang University, Seoul, 156-756, Republic of Korea), Kameda, D.(RIKEN Nishina Center, RIKEN, 2-1 Hirosawa, Wako-shi, Saitama, 351-0198, Japan), Kim, G.D.(Rare Isotope Science Project, Institute for Basic Science, Daejeon, 305-811, Republic of Korea), Kim, Y.-K.(Rare Isotope Science Project, Institute for Basic Science, Daejeon, 305-811, Republic of Korea), Kojouharov, I.(GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt, 64291, Germany), Kubo, T.(RIKEN Nishina Center, RIKEN, 2-1 Hirosawa, Wako-shi, Saitama, 351-0198, Japan), Kurz, N.(GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt, 64291, Germany), Kwon, Y.K.(Rare Isotope Science Project, Institute for Basic Science, Daejeon, 305-811, Republic of Korea), Li, Z.(School of Physics, State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing, 100871, China), Sakurai, H.(RIKEN Nishina Center, RIKEN, 2-1 Hirosawa, Wako-shi, Saitama, 351-0198, Japan), Schaffner, H.(GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt, 64291, Germany), Steiger, K.(Physik Department E12, Technische Universität München, Garching, D-85748, Germany), Suzuki, H.(RIKEN Nishina Center, RIKEN, 2-1 Hirosawa, Wako-shi, Saitama, 351-0198, Japan), Takeda, H.(RIKEN Nishina Center, RIKEN, 2-1 Hirosawa, Wako-shi, Saitama, 351-0198, Japan), Vajta, Zs.(MTA Atomki, P.O. Box 51, Debrecen, H-4001, Hungary), Watanabe, H.(RIKEN Nishina Center, RIKEN, 2-1 Hirosawa, Wako-shi, Saitama, 351-0198, Japan), Wu, J.(School of Physics, State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing, 100871, China), Yagi, A.(Department of Physics, Osaka University, Machikaneyama-machi 1-1, Toyonaka, Osaka, 560-0043, Japan), Yoshinaga, K.(Department of Physics, Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba, Japan), Benzoni, G.(INFN, Sezione di Milano, via Celoria 16, Milano, I-20133, Italy), Bönig, S.(Institut für Kernphysik, Technische Universität Darmstadt, Darmstadt, D-64289, Germany), Chae, K.Y.(Department of Physics, Sungkyunkwan University, Suwon, 440-746, Republic of Korea), Coraggio, L.(Istituto Nazionale di Fisica Nucleare, Complesso Universitario di Monte S. Angelo, Napoli, I-80126, Italy), Covello, A.(Dipartimento di Fisica, Università di Napoli Federico II, Complesso Universitario di Monte S. Angelo, Napoli, I-80126, Italy), Daugas, J.-M.(CEA, DAM, DIF, Arpajon cedex, 91297, France), Drouet, F.(LPSC, Université Joseph Fourier Grenoble 1, CNRS/IN2P3, Institut National Polytechnique de Grenoble, Grenoble cedex, F-38026, France), Gadea, A.(Instituto de Física Corpuscular, CSIC, Univ. of Valencia, Paterna, E-46980, Spain), Gargano, A.(Istituto Nazionale di Fisica Nucleare, Complesso Universitario di Monte S. Angelo, Napoli, I-80126, Italy), Ilieva, S.(Institut für Kernphysik, Technische Universität Darmstadt, Darmstadt, D-64289, Germany), Kondev, F.G.(Nuclear Engineering Division, Argonne National Laboratory, Argonne, IL, 60439, USA), Kröll, T.(Institut für Kernphysik, Technische Universität Darmstadt, Darmstadt, D-64289, Germany), Lane, G.J.(Department of Nuclear Physics, Research School of Physical Sciences and Engineering, Australian National University, Canberra, ACT 0200, Australia), Montaner-Pizá, A.(Instituto de Física Corpuscular, CSIC, Univ. of Valencia, Paterna, E-46980, Spain), Moschner, K.(IKP, University of Cologne, Cologne, D-50937, Germany), Mücher, D.(Institut für Kernphysik, Technische Universität Darmstadt, Darmstadt, D-64289, Germany), Naqvi, F.(Wright Nuclear Structure Laboratory, Yale University, New Haven, CT, 06520-8120, USA), Niikura, M.(Department of Physics, University of Tokyo, Japan, Hongo 7-3-1, Bunkyo-ku, Tokyo, 113-0033), Nishibata, H.(Department of Physics, Osaka University, Machikaneyama-machi 1-1, Toyonaka, Osaka, 560-0043, Japan), Odahara, A.(Department of Physics, Osaka University, Machikaneyama-machi 1-1, Toyonaka, Osaka, 560-0043, Japan), Orlandi, R.(Instituut voor Kern- en Stralingsfysica, K.U. Leuven, Heverlee, B-3001, Belgium), Patel, Z.(Department of Physics, University of Surrey, Guildford, GU2 7XH, United Kingdom), Podolyák, Zs.(Department of Physics, University of Surrey, Guildford, GU2 7XH, United Kingdom), and Wendt, A.(IKP, University of Cologne, Cologne, D-50937, Germany)

Subjects
Isomeric decays, Shell model calculations, Nuclear Theory, Physics::Atomic and Molecular Clusters, Transition strengths, Nuclear Experiment, lcsh:Physics, lcsh:QC1-999
Abstract

The decay of an isomeric state in the neutron-rich nucleus 129Cd has been observed via the detection of internal conversion and Compton electrons providing first experimental information on excited states in this nucleus. The isomer was populated in the projectile fission of a 238U beam at the Radioactive Isotope Beam Factory at RIKEN. From the measured yields of γ-rays and internal conversion electrons, a multipolarity of E3 was tentatively assigned to the isomeric transition. A half-life of T1/2=3.6(2) ms was determined for the new state which was assigned a spin of (21/2+), based on a comparison to shell model calculations performed using state-of-the-art realistic effective interactions. Keywords: Isomeric decays, Transition strengths, Shell model calculations

Published
2014

2. Phosphosilicate Multimode Optical Fiber for Sensing and Diagnostics at Inertial Confinement Fusion Facilities

Author

Philippe Paillet, Sylvain Girard, Vincent Goiffon, O. Duhamel, Adriana Morana, Damien Lambert, Vincenzo De Michele, Cosimo Campanella, Gilles Melin, Thierry Robin, Jeoffray Vidalot, Arnaud Meyer, Aziz Boukenter, Youcef Ouerdane, Emmanuel Marin, Vladimir Yu. Glebov, Gregory Pien, Institut Supérieur de l'Aéronautique et de l'Espace - ISAE-SUPAERO (FRANCE), CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), Laboratoire Hubert Curien (LHC), Institut d'Optique Graduate School (IOGS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), Institut Supérieur de l'Aéronautique et de l'Espace (ISAE-SUPAERO), iXBlue Photonics, Laboratory for lasers energetics - LLE (New-York, USA), and University of Rochester [USA]

Subjects
[SPI]Engineering Sciences [physics], Radiation-induced attenuation (RIA), Autre, Dosimetry, Fusion, neutrons, Radiation effects, Optical fibers, Electrical and Electronic Engineering, Instrumentation
Abstract

We characterized the radiation response in the visible domain of a new multimode graded-index (GI) phosphosilicate optical fiber (GIMMF), exposed to the harsh environment (pulses of 14-MeV neutrons, X-rays, and γ -rays) associated with laser experiments at the OMEGA facility. The growth of permanent radiation-induced attenuation (RIA) was measured in situ after a series of laser shots involving a large production of 14-MeV neutrons (yields > 10^14 n per shot). RIA linearly increases with accumulated neutron fluence without recovery between shots. The obtained results allow a precise evaluation of this GIMMF vulnerability when implemented as part of laser or plasma diagnostics. Our work also reveals the potential of this class of optical fiber to serve as a radiation monitor in the radiation-rich mixed environments of megajoule class laser facilities and to provide a very fast and online estimation of the accumulated deposited dose at various locations of their experimental halls. In our experimental test configuration at OMEGA, 14-MeV neutrons are estimated to contribute to about 55% of the total deposited dose on the fibers, and the other optical losses are related to X-ray and γ -ray contributions. Those measurements could be, for example, benchmarked to the radiation maps obtained by Monte Carlo simulation tools, potentially facilitating the evaluation of the aging of diagnostics, components, and systems as well as their maintenance operations.

Published
2022
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3. Débruitage multi-modal d'images radar à synthèse d'ouverture par apprentissage profond auto-supervisé

Author

Gaya, Victor, Dalsasso, Emanuele, Denis, Loïc, Tupin, Florence, Pinel-Puysségur, Béatrice, Guérin, Cyrielle, CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), Image, Modélisation, Analyse, GEométrie, Synthèse (IMAGES), Laboratoire Traitement et Communication de l'Information (LTCI), Institut Mines-Télécom [Paris] (IMT)-Télécom Paris-Institut Mines-Télécom [Paris] (IMT)-Télécom Paris, Département Images, Données, Signal (IDS), Télécom ParisTech, Institut Mines-Télécom [Paris] (IMT)-Télécom Paris, Télécom Paris, Institut Polytechnique de Paris (IP Paris), Laboratoire Hubert Curien (LHC), Institut d'Optique Graduate School (IOGS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), and ANR-21-ASTR-0011,ASTRAL,Apprentissage StaTistique pour l'imageRie sAr muLtidimensionnelle(2021)

Subjects
[SDU.STU]Sciences of the Universe [physics]/Earth Sciences, [SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing
Abstract

International audience; -L'observation de la Terre a été largement facilitée depuis de nombreuses années grâce à l'utilisation des satellites imageurs radar à synthèse d'ouverture (SAR), qui offrent des capacités d'imagerie indépendantes des conditions météorologiques. Toutefois, l'interprétation de ces images SAR est complexe en raison de la présence de bruit inhérent à l'imagerie cohérente. En effet, des fluctuations apparaissent dans les images, notamment là où la réflectivité radar est élevée. Ainsi, de nombreuses méthodes ont été développées pour réduire le bruit présent dans ces images, notamment des méthodes neuronales particulièrement efficaces. Dans cet article, nous proposons d'étudier comment l'ajout d'une donnée auxiliaire comme une image optique peut améliorer la restauration de la réflectivité dans ce cadre.

Published
2023

4. Monotonic diamond and DDFV type finite-volume schemes for 2D elliptic problems

Author

Blanc, Xavier, Hermeline, Francois, Labourasse, Emmanuel, Patela, Julie, Laboratoire Jacques-Louis Lions (LJLL (UMR_7598)), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Laboratoire en Informatique Haute Performance pour le Calcul et la simulation (LIHPC), DAM Île-de-France (DAM/DIF), Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, and CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF)

Subjects
Order 2, Monotonicity, Elliptic problem, Finite volume method, DDFV, [MATH.MATH-AP]Mathematics [math]/Analysis of PDEs [math.AP]
Abstract

The DDFV (Discrete Duality Finite Volume) method is a finite volume scheme mainly dedicated to diffusion problems, with some outstanding properties. This scheme has been found to be one of the most accurate finite volume methods for diffusion problems. In the present paper, we propose a new monotonic extension of DDFV, which can handle discontinuous tensorial diffusion coefficient. Moreover, we compare its performance to a diamond type method with an original interpolation method relying on polynomial reconstructions. Monotonicity is achieved by adapting the method from [44, 19, 49, 18] to our schemes. Such a technique does not require the positiveness of the secondary unknowns. We show that the two new methods are second-order accurate and are indeed monotonic on some challenging benchmarks as a Fokker-Planck problem.

Published
2023

5. Arbitrary-order monotone finite-volume schemes for 1D elliptic problems

Author

Xavier Blanc, Francois Hermeline, Emmanuel Labourasse, Julie Patela, Laboratoire Jacques-Louis Lions (LJLL (UMR_7598)), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Laboratoire en Informatique Haute Performance pour le Calcul et la simulation (LIHPC), DAM Île-de-France (DAM/DIF), Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, and CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF)

Subjects
Elliptic problems, Computational Mathematics, Monotonicity, Finite volume method, Applied Mathematics, MSC: 65N06, 65N08, 65N12, [MATH.MATH-AP]Mathematics [math]/Analysis of PDEs [math.AP], High order, [MATH.MATH-NA]Mathematics [math]/Numerical Analysis [math.NA]
Abstract

International audience; When solving numerically an elliptic problem, it is important in most applications that the scheme used preserves the positivity of the solution. When using finite volume schemes on deformed mesh, the question has been solved rather recently. Such schemes are usually (at most) second order convergent, and nonlinear. On the other hand, many high-order schemes have been proposed, that do not ensure positivity of the solution. In this paper we propose a very high-order monotone (that is, positivity preserving) numerical method for elliptic problems in 1D. We prove that this method converges to an arbitrary order and is indeed monotone. We also show how to handle discontinuous sources or diffusion coefficients, while keeping the order of convergence. We assess the new scheme, on several test problems, with arbitrary (regular, distorted, random) meshes.

Published
2023
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6. Assessing the efficiency of water-soluble organic compound biodegradation in clouds under various environmental conditions

Author

Lucas Pailler, Nolwenn Wirgot, Muriel Joly, Pascal Renard, Camille Mouchel-Vallon, Angelica Bianco, Maud Leriche, Martine Sancelme, Aurélie Job, Luc Patryl, Patrick Armand, Anne-Marie Delort, Nadine Chaumerliac, Laurent Deguillaume, Laboratoire de Météorologie Physique (LaMP), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA), Institut de Chimie de Clermont-Ferrand (ICCF), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA)-Institut national polytechnique Clermont Auvergne (INP Clermont Auvergne), Université Clermont Auvergne (UCA)-Université Clermont Auvergne (UCA), Laboratoire d'aérologie (LAERO), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), and Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)

Subjects
Chemistry (miscellaneous), [SDE]Environmental Sciences, Environmental Chemistry, Pollution, Analytical Chemistry
Abstract

Biodegradation is competitive with photochemistry, especially in summer and at night. Formic acid is the most impacted compound.

Published
2023
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7. Neutron displacement damage cross-section in GaN: numerical evaluations and differences with Si

Author

Damien Lambert, Julien Parize, Nicolas Richard, Mélanie Raine, Olivier Duhamel, Claude Marcandella, Arthur Losquin, Anne Hemeryck, Christophe Inguimbert, Philippe Paillet, CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), Équipe Modélisation Multi-niveaux des Matériaux (LAAS-M3), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT), ONERA / DPHY, Université de Toulouse [Toulouse], and ONERA-PRES Université de Toulouse

Subjects
cross-section, [PHYS]Physics [physics], Nuclear and High Energy Physics, [SPI]Engineering Sciences [physics], neutron, Nuclear Energy and Engineering, Displacement Damage, TNID, Geant4, Electrical and Electronic Engineering, NIEL, Monte Carlo, GaN
Abstract

International audience; The displacement damage cross-section of the neutron-GaN interaction is calculated in the energy range from meV to GeV. Different calculation methods are used and discussed to estimate the modeling uncertainty. The Non-ionizing energy loss (NIEL) and the relative damage factors are also deduced. Differences with the neutron-Silicon interactions are presented and the impacts on the estimation of Total Non-Ionizing Dose (TNID) levels are evaluated as a function of neutron energy.

Published
2023
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8. Performance Improvements of Parallel Applications thanks to MPI-4.0 Hints

Author

Moraru, Maxim, Roussel, Adrien, Taboada, Hugo, Pérache, Marc, Jaillet, Christophe, Krajecki, Michaël, Laboratoire d'Informatique en Calcul Intensif et Image pour la Simulation (LICIIS), Université de Reims Champagne-Ardenne (URCA), Laboratoire de Recherche Conventionné DIGIT (LRC CEA/URCA DIGIT), Université de Reims Champagne-Ardenne (URCA)-CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), Laboratoire en Informatique Haute Performance pour le Calcul et la simulation (LIHPC), DAM Île-de-France (DAM/DIF), Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), and IEEE

Subjects
MPI Matching, HPC, Distributed programming, [INFO]Computer Science [cs], MPI 4.0 Sessions, [INFO.INFO-DC]Computer Science [cs]/Distributed, Parallel, and Cluster Computing [cs.DC]
Abstract

International audience; HPC systems have experienced significant growth over the past years, with modern machines having hundreds of thousands of nodes. Message Passing Interface (MPI) is the de facto standard for distributed computing on these architectures. On the MPI critical path, the message-matching process is one of the most time-consuming operations. In this process, searching for a specific request in a message queue represents a significant part of the communication latency. So far, no miracle algorithm performs well in all cases. This paper explores potential matching specializations thanks to hints introduced in the latest MPI 4.0 standard. We propose a hash-table-based algorithm that performs constant time message-matching for no wildcard requests. This approach is suitable for intensive point-to-point communication phases in many applications (more than 50% of CORAL benchmarks). We demonstrate that our approach can improve the overall execution time of real HPC applications by up to 25%. Also, we analyze the limitations of our method and propose a strategy for identifying the most suitable algorithm for a given application. Indeed, we apply machine learning techniques for classifying applications depending on their message pattern characteristics.

Published
2022
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9. $^{240}$Pu/$^{239}$Pu signatures allow refining the chronology of radionuclide fallout in South America

Author

Pierre-Alexis Chaboche, Fabien Pointurier, Pierre Sabatier, Anthony Foucher, Tales Tiecher, Jean P.G. Minella, Marcos Tassano, Amélie Hubert, Sergio Morera, Stéphane Guédron, Christophe Ardois, Béatrice Boulet, Catherine Cossonnet, Pablo Cabral, Mirel Cabrera, Guillermo Chalar, Olivier Evrard, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Géochimie Des Impacts (GEDI), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), Environnements, Dynamiques et Territoires de Montagne (EDYTEM), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Universidade Federal do Rio Grande do Sul [Porto Alegre] (UFRGS), Universidade Federal de Santa Maria = Federal University of Santa Maria [Santa Maria, RS, Brazil] (UFSM), Facultad de Ciencias (UDELAR), Instituto Geofísico del Perú (IGP), Institut des Sciences de la Terre (ISTerre), Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Gustave Eiffel-Université Grenoble Alpes (UGA), Laboratoire de métrologie de la radioactivité dans l'environnement (IRSN/PSE-ENV/SAME/LMRE), Service d'analyses et de métrologie de l'environnement (IRSN/PSE-ENV/SAME), and Institut de Radioprotection et de Sûreté Nucléaire (IRSN)-Institut de Radioprotection et de Sûreté Nucléaire (IRSN)

Subjects
Environmental Engineering, Nuclear weapon tests, Geochronology, Plutonium isotopes, [SDV.SA.SDS]Life Sciences [q-bio]/Agricultural sciences/Soil study, Pollution, Panoply, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, [SDE]Environmental Sciences, Soil erosion, Environmental Chemistry, [SDU.STU.GM]Sciences of the Universe [physics]/Earth Sciences/Geomorphology, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, Waste Management and Disposal
Abstract

International audience; Atmospheric nuclear tests (1945-1980) have led to radioactive fallout across the globe. French tests in Polynesia (1966-1974) may influence the signature of fallout in South America in addition to those conducted by USA and former USSR until 1963 in the Northern hemisphere. Here, we compiled the $^{240}$Pu/$^{239}$Pu atom ratios reported for soils of South America and conducted additional measurements to examine their latitudinal distributions across this continent. Significantly lower ratio values were found in the 20-45° latitudinal band (0.04 to 0.13) compared to the rest of the continent (up to 0.20) and attributed to the contribution of the French atmospheric tests to the ultra-trace plutonium levels found in these soils. Based on sediment cores collected in lakes of Chile and Uruguay, we show the added value of measuring $^{240}$Pu/$^{239}$Pu atom ratios to refine the age models of environmental archives in this region of the world.

Published
2022
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10. Enhancing MPI+OpenMP task based applications for heterogenous architectures with GPU support

Author

Ferat, Manuel, Pereira, Romain, Roussel, Adrien, Carribault, Patrick, Steffenel, Luiz-Angelo, Gautier, Thierry, Laboratoire d'Informatique en Calcul Intensif et Image pour la Simulation (LICIIS), Université de Reims Champagne-Ardenne (URCA), Laboratoire de Recherche Conventionné DIGIT (LRC CEA/URCA DIGIT), Université de Reims Champagne-Ardenne (URCA)-CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), DAM Île-de-France (DAM/DIF), Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Algorithms and Software Architectures for Distributed and HPC Platforms (AVALON), Laboratoire de l'Informatique du Parallélisme (LIP), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-Inria Lyon, Institut National de Recherche en Informatique et en Automatique (Inria), Laboratoire en Informatique Haute Performance pour le Calcul et la simulation (LIHPC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Michael Klemm, Bronis R. de Supinski, Jannis Klinkenberg, Brandon Neth, and Present results have been obtained within the frame of DIGIT, Contractual Research Laboratory between CEA, CEA/DAM-Île de France center and the University of Reims Champagne Ardenne.

Subjects
Task programming, MPI+OpenMP, GPU Computing, OpenMP, [INFO]Computer Science [cs], Asynchronism, [INFO.INFO-DC]Computer Science [cs]/Distributed, Parallel, and Cluster Computing [cs.DC]
Abstract

Editors: Michael Klemm; Bronis R. de Supinski et al.; International audience; Heterogeneous supercomputers are widespread over HPC systems and programming efficient applications on these architectures is a challenge. Task-based programming models are a promising way to tackle this challenge. Since OpenMP 4.0 and 4.5, the target directives enable to offload pieces of code to GPUs and to express it as tasks with dependencies. Therefore, heterogeneous machines can be programmed using MPI+OpenMP(task+target) to exhibit a very high level of concurrent asynchronous operations for which data transfers, kernel executions, communications and CPU computations can be overlapped. Hence, it is possible to suspend tasks performing these asynchronous operations on the CPUs and to overlap their completion with another task execution. Suspended tasks can resume once the associated asynchronous event is completed in an opportunistic way at every scheduling point. We have integrated this feature into the MPC framework and validated it on a AXPY microbenchmark and evaluated on a MPI+OpenMP(tasks) implementation of the LULESH proxy applications. The results show that we are able to improve asynchronism and the overall HPC performance, allowing applications to benefit from asynchronous execution on heterogeneous machines.

Published
2022
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11. Triangular metric-based mesh adaptation for compressible multi-material flows in semi-Lagrangian coordinates

Author

del Pino, Stéphane, Marmajou, Isabelle, CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), Laboratoire en Informatique Haute Performance pour le Calcul et la simulation (LIHPC), DAM Île-de-France (DAM/DIF), Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction des Applications Militaires (DAM), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay

Subjects
History, Numerical Analysis, Polymers and Plastics, Physics and Astronomy (miscellaneous), Maximum Principle, Applied Mathematics, Lagrange, [INFO.INFO-MO]Computer Science [cs]/Modeling and Simulation, Industrial and Manufacturing Engineering, Computer Science Applications, Computational Mathematics, Gas dynamics, Modeling and Simulation, adaptive mesh refinement, Business and International Management, [MATH.MATH-NA]Mathematics [math]/Numerical Analysis [math.NA], finite-volume
Abstract

In this paper, we propose an adaptive mesh refinement method for 2D multi-material compressible nonviscous flows in semi-Lagrangian coordinates. The mesh adaptation procedure is local and relies on discrete metric field evaluation. The remapping method is second-order accurate and we prove its stability. We propose a multi-material treatment using two ingredients: the local remeshing is performed in a way to reduce as much as possible mixture creation and an interface reconstruction method is used to avoid material diffusion in mixing cells. The obtained method is almost Lagrangian and can be implemented in a parallel framework. We provide some numerical tests which attest the validity of the method and its robustness.

Published
2023
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12. Activation–Relaxation Technique: An efficient way to find minima and saddle points of potential energy surfaces

Author

Antoine Jay, Miha Gunde, Nicolas Salles, Matic Poberžnik, Layla Martin-Samos, Nicolas Richard, Stefano de Gironcoli, Normand Mousseau, Anne Hémeryck, Équipe Modélisation Multi-niveaux des Matériaux (LAAS-M3), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT), CNR Istituto Officina dei Materiali (IOM), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), Scuola Internazionale Superiore di Studi Avanzati / International School for Advanced Studies (SISSA / ISAS), and Université de Montréal (UdeM)

Subjects
[PHYS]Physics [physics], atomistic diffusion, General Computer Science, catalysis reactions, saddle-point search, General Physics and Astronomy, General Chemistry, Computational Mathematics, atomistic modelling, Mechanics of Materials, [CHIM]Chemical Sciences, General Materials Science, activated mechanisms, activation-relaxation technique
Abstract

International audience; The Activation–Relaxation Technique (ARTn) is an efficient technique for finding the minima and saddle points of multidimensional functions such as the potential energy surface of atomic systems in chemistry. In this work we detail and illustrate significant improvements made to the algorithm, regarding both preprocessing and the activation process itself. As showcased, these advances significantly reduce ARTn computational costs, especially when applied with ab initio description. With these modifications, ARTn establishes itself as a very efficient method for exploring the energy landscape and chemical reactions associated with complex mechanisms.

Published
2022
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13. Ionization by electron impacts and ionization potential depression

Author

Djamel Benredjem, Jean-Christophe Pain, Annette Calisti, Sandrine Ferri, Laboratoire Aimé Cotton (LAC), Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), Physique des interactions ioniques et moléculaires (PIIM), and Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS.PHYS.PHYS-COMP-PH]Physics [physics]/Physics [physics]/Computational Physics [physics.comp-ph], [PHYS.PHYS.PHYS-ATOM-PH]Physics [physics]/Physics [physics]/Atomic Physics [physics.atom-ph], [PHYS.PHYS.PHYS-PLASM-PH]Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph], Condensed Matter Physics, [INFO.INFO-MO]Computer Science [cs]/Modeling and Simulation, Atomic and Molecular Physics, and Optics
Abstract

We calculate the cross-section of ionization by free-electron impacts in high or moderate density plasmas. We show that the so-called ionization potential depression (IPD) strongly affects the magnitude of the cross-section in the high-density domain. We use the well-known IPD formulas of Stewart–Pyatt and Ecker–Kröll. A more recent approach based on classical molecular dynamics simulation is also investigated. The latter provides an alternative way to calculate IPD values. At near-solid densities the effects of the free-electron degeneracy should be investigated. The rates are then calculated within the Fermi–Dirac statistics. We first use the semi-empirical formula of Lotz for ionization cross-section. The results may differ significantly from measured cross-sections or calculations with reliable atomic codes. Then, in a second step, we propose a new formula that combines the Lotz formula and a polynomial expansion in terms of the ratio of the energy of the incident electron and the ionization energy. The coefficients of the polynomial expansion are adjusted to fit the cross-section provided by robust atomic codes. A great advantage of the new formula is that it allows a fully analytical calculation of the ionization rate. Our results are compared to experiments measuring IPDs, cross-sections and rate coefficients on aluminum at high and moderate densities and on Be-like CNO ions.

Published
2022
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14. An Overview Of The Stratelec Project (Stratéole-2 Atmospheric Electricity)

Author

Defer, E, Célestin, S, Pallu, M, Farges, T, Kolmašová, I, Santolik, O, Trompier, F, Hertzog, A, Vargas, A, Venel, S, Laboratoire d'aérologie (LAERO), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), Laboratoire de dosimétrie des rayonnements ionisants (IRSN/PSE-SANTE/SDOS/LDRI), Service de dosimétrie (IRSN/PSE-SANTE/SDOS), Institut de Radioprotection et de Sûreté Nucléaire (IRSN)-Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Laboratoire de Météorologie Dynamique (UMR 8539) (LMD), Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-École des Ponts ParisTech (ENPC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), and Centre National d'Études Spatiales [Toulouse] (CNES)

Subjects
[SDE.IE]Environmental Sciences/Environmental Engineering
Abstract

International audience; The STRATELEC (STRatéole-2 ATmospheric ELECtricity) project, funded by the French Space Agency CNES, aims at deploying new atmospheric electricity instrumentation during the last Stratéole-2 balloon campaign [1]. The multidisciplinary STRATELEC project focuses on i) measuring the electrical state of the atmosphere and the production of high-energy radiation through in situ and remote sensing measurements, ii) identifying state-of-the-art and emerging technologies to populate and build the STRATELEC instrumentation package, and iii) contributing to additional scientific returns on any international space mission dedicated to lightning detection and more generally to the study of electrodynamic couplings in the terrestrial atmosphere-ionosphere-magnetosphere system.

Published
2022

15. Imagerie acoustique de la propagation d’un choc dans un métallique

Author

Ducousso, Mathieu, Cuenca, Eduardo, Videau, Laurent, Berthe, Laurent, Coulouvrat, François, SAFRAN Group, CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), École Nationale Supérieure des Arts et Métiers (ENSAM), Sorbonne Université (SU), Société Française d'Acoustique, and Laboratoire de Mécanique et d'Acoustique

Subjects
[PHYS.MECA.ACOU]Physics [physics]/Mechanics [physics]/Acoustics [physics.class-ph]
Abstract

Nous présentons une méthode pour imager la propagation d'une onde de choc dans une couche métallique épaisse et opaque. [1] L'onde de choc est générée par une source laser impulsionnelle de puissance (>GW/cm², ~10 ns) focalisée en surface d’une cible métallique (épaisseur ~ 10 mm). Suite à un tel chargement laser, la surface de la cible est sublimée en un plasma dense qui, en se détendant, induit la propagation d’un choc dans le volume du matériau, d’intensité crête quelques GPa ou centaines de m/s en vitesse. Les applications du choc laser vont de l'ingénierie [2] à la caractérisation des diagrammes de phase aux hautes pressions et températures. [3] Cette dernière application a été l'une des principales motivations au développement des lasers à électrons libres (X-FEL), pour des applications d’astrophysique. La détection X est essentiellement liée à une variation locale de densité générée par le choc. Ici, une onde sonde plane ultrasonore (15 MHz), contra-propagative par rapport au choc, est émise par une barrette linéaire multi-éléments (x128). Cette onde est pour partie diffractée par la variation d’impédance acoustique engendrée par le choc. Cette diffraction est détectée par la même sonde multi-éléments. Un délai d’émission entre le choc et l’onde sonde permet d’imager la propagation du choc dans l’ensemble du volume de l’échantillon. Une détection résolue en temps et en espace, et permettant d’imager la propagation du choc dans le cœur de la structure, est ainsi obtenue. Des éléments théoriques, proposés par Burgers et Brillouin au milieu du 20ème siècle, et complétés par nos propres études théoriques et numériques, permettent une première interprétation des résultats expérimentaux. [1] Ducousso et al., Phys. Rev. Applied, 15 (2021) [2] Ducousso et al., Appl. Phys. Lett., 112 (2018). [3] Denoeud et al., PNAS, 113 (2016).

Published
2022

16. Analyse statistique de la propagation des ondes de souffle en environnement complexe

Author

Gainville, Olaf, Leconte, Roman, Marchiano, Régis, CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), Institut Jean Le Rond d'Alembert (DALEMBERT), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Société Française d'Acoustique, and Laboratoire de Mécanique et d'Acoustique

Subjects
[PHYS.MECA.ACOU]Physics [physics]/Mechanics [physics]/Acoustics [physics.class-ph]
Abstract

La propagation acoustique des ondes de souffle est affectée par la topographie, la végétation et les conditions météorologiques. Ces effets comportent une part importante d'incertitudes du fait de la méconnaissance et de la nature aléatoire du milieu de propagation. Afin de quantifier ces incertitudes, des enregistrements acoustiques ont été réalisés autour d'un site pyrotechnique industriel jusqu'à 20 km pour environ 600 explosions d'énergies comprises entre 300 et 500 kg d'équivalent TNT. Ces mesures sont classifiées en fonction des conditions de propagation puis comparées à des simulations numériques. Les incertitudes associées à la source explosive sont analysées par des méthodes de clustering. Les incertitudes dues à la méconnaissance des grandes échelles de l'atmosphère sont analysées à l'aide d'un modèle de propagation unidirectionnel couplé avec des polynômes de chaos. Les résultats préliminaires montrent que l'incertitude associée à l'atmosphère est dominante et que son amplitude est en partie retrouvée par les modèles.

Published
2022

17. On the use of infrasound for evaluating long range middle atmospheric variability: application for early notification of Volcanic Ash Advisory Centres

Author

Le Pichon, Alexis, Ceranna, Lars, Hereil, Philippe, Mialle, Pierrick, CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), Météo-France, Société Française d'Acoustique, and Laboratoire de Mécanique et d'Acoustique

Subjects
[PHYS.MECA.ACOU]Physics [physics]/Mechanics [physics]/Acoustics [physics.class-ph]
Abstract

Global scale infrasound observations confirm that the detection capability of the International Monitoring System (IMS) deployed to monitor compliance with the Comprehensive Nuclear-Test ban Treaty (CTBT) is highly variable in space and time. Existing empirical yield-scaling relations simplified the complexities of infrasound propagation as the stratospheric wind correction applied does not account for an accurate description of the middle atmosphere along the propagation path. In order to reduce the variance in the calculated transmission loss, massive frequency and range-dependent full-wave propagation simulations are carried out. A wide range of realistic atmospheric scenarios are explored including fine-scale atmospheric structures derived from a two-dimensional horizontal wave number spectrum model. In the context of the future verification of the CTBT, this approach helps advance the development of network performance simulations in higher resolution and the evaluation of middle atmospheric models at a global scale with limited computational resources. It also offers avenues for civilian applications such as the use of infrasound data in support of the International Civil Aviation Organization (ICAO) International Airways Volcano Watch. Continuous progress has been made in recent years initiated by a collaboration between CTBTO and the Toulouse Volcanic Ash Advisory Centre (VAAC), resulting in the development of the Volcanic Information System (VIS) under the ARISE (Atmospheric dynamics Research Infra-Structure in Europe) project. Examples of notifications of recent volcanic activity based on global infrasound observations will be presented.

Published
2022

18. Reconstruction acoustique des éclairs d'orages : caractérisation de la distribution géométrique du rayonnement du tonnerre

Author

Bestard, Damien, Farges, Thomas, Coulouvrat, François, Sorbonne Université (SU), CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), Société Française d'Acoustique, and Laboratoire de Mécanique et d'Acoustique

Subjects
[PHYS.MECA.ACOU]Physics [physics]/Mechanics [physics]/Acoustics [physics.class-ph]
Abstract

Pendant la campagne EXAEDRE (Corse, 2018), caractérisant les nuages orageux et l'activité électrique, un réseau triangulaire de largeur 30 m avec 4 microphones, a enregistré sur la bande [1-125 Hz] le tonnerre associé aux éclairs. La recherche de signaux cohérents permet de déterminer, par bandes de fréquences, la vitesse apparente du tonnerre et son azimut [Cansi, Geophys. Res. Lett., 1995]. Connaissant l’horaire de l'éclair selon Météorage (système électromagnétique basse fréquence [1-350 kHz] de localisation de la foudre au sol), et la vitesse locale du son, on reconstruit les sources sonores cohérentes au sein d'un éclair. Leur colocalisation avec les détections électromagnétiques à hautes ([60-66 MHz], SAETTA) et basses fréquences montre l'efficacité et la précision de la méthode, déjà observées (campagne SOP1, Cévennes, 2012 [Gallin et al., J. Geophys. Res. Atmos., 2016, Lacroix et al., J. Geophys. Res. Atmos, 2018, Lacroix et al., Geophys. Res. Lett., 2019]). L'algorithme fournit également la pression RMS des détections. En supposant chaque source ponctuelle, les distances de propagation sources-réseau et l’absorption atmosphérique sont compensées, pour déterminer la puissance acoustique de chaque source. Pour EXAEDRE, 54 évènements ont été étudiés pour deux orages, l’un avec une activité électrique plus intense que l’autre. La localisation de l'énergie indique une distribution fortement hétérogène au sein de l'éclair, avec des sources intenses fréquemment concentrées à proximité du sol, et des parties intranuageuses moins énergétiques. Les événements EXAEDRE ayant une distribution d'énergie homogène sont assez rares. Cette répartition énergétique est également validée par l’utilisation d’autres microphones isolés dans un rayon de 10km. Pour SOP1, les arcs nuage-sol sont plus fréquemment homogènes, même si des cas hétérogènes sont également observés. [Données issues du programme EXAEDRE, dirigé par E. Defer. Etude dans le cadre du Laboratoire Contractuel de Recherche LETMA entre le CEA, le CNRS, l'Ecole Centrale Lyon, C-Innov, et Sorbonne Université].

Published
2022

19. PLetma - Plateforme numérique parallèle pour la simulation des infrasons

Author

Khodr, Codor, Dragna, Didier, Blanc-Benon, Philippe, Marchiano, Régis, Aubry, Ludovic, Gainville, Olaf, Millet, Christophe, Laboratoire de Mecanique des Fluides et d'Acoustique (LMFA), École Centrale de Lyon (ECL), Université de Lyon-Université de Lyon-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Institut Jean Le Rond d'Alembert (DALEMBERT), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), Société Française d'Acoustique, and Laboratoire de Mécanique et d'Acoustique

Subjects
[PHYS.MECA.ACOU]Physics [physics]/Mechanics [physics]/Acoustics [physics.class-ph]
Abstract

La Plateforme numérique du Laboratoire d'Étude et de Modélisation en Acoustique (PLetma) regroupe les codes de calcul scientifique développés par les institutions partenaires du LETMA depuis 2015. Elle contient quatre codes différents: tracé de rayons, méthode unidirectionnelle non-linéaire, modes normaux et méthode Navier-Stokes directe. L'objectif de la plateforme est de pourvoir un ensemble d'outils complémentaires pour la modélisation de signaux infrasonores large bande dans une atmosphère inhomogène et en mouvement. Elle permet de couvrir un large éventail de problèmes de propagation basse fréquence issus de la géophysique ou de l'ingénierie. Implémentée en MPI et OpenMP, la plateforme tire profit du calcul parallèle pour réduire le coût des simulations de grande taille. PLetma donne une infrastructure pour l'inclusion d'outils de modélisation de la propagation et de la variabilité du problème. Des comparaisons ont été effectuées entre les différentes méthodes sur un cas test (Sabatini et al., JASA 2016). Des analyses de sensibilité ont été effectuées pour comprendre l'effet des paramètres environnementaux sur la propagation des infrasons sur de longues distances. [Ce travail a été effectué dans le cadre du LETMA (Laboratoire ETudes et Modélisation Acoustique), un laboratoire de recherche contractuel entre le CEA, le CNRS, l'École Centrale de Lyon, C-Innov, et Sorbonne Université.]

Published
2022

20. Common defects in diamond lattices as instances of the general T ⊗ (e+t2) Jahn-Teller effect

Author

Gabriela Herrero-Saboya, Layla Martin-Samos, Nicolas Richard, Anne Hemeryck, CNR Istituto Officina dei Materiali (IOM), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), Équipe Modélisation Multi-niveaux des Matériaux (LAAS-M3), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), and Université de Toulouse (UT)

Subjects
[PHYS]Physics [physics], Physics and Astronomy (miscellaneous), [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], General Materials Science
Abstract

International audience; Finding the ground-state configuration of point defects in semiconductors is in general a high-dimensional optimization problem. However, their adiabatic potential energy surfaces (APES) can be described with few effective coordinates by exploiting symmetry arguments within the Jahn-Teller (JT) theoretical framework. In this paper, we propose a general framework, that combines group theory and ab initio calculations, to build a full picture of common defects in diamond lattices (vacancies and substitutional impurities) as instances of the general T ⊗ (e + t 2) APES. Starting from the original tetrahedral symmetry, we consider all possible JT symmetries and we numerically investigate the shape of the APES by targeting the minimum energy path between equivalent JT distortions taking as examples the vacancy (V) and the metallic impurities Pd, Pt, and Au in crystalline silicon.

Published
2022
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21. Experimental observation of the M1 scissors mode in $^{254}No$

Author

F.L. Bello Garrote, A. Lopez-Martens, A.C. Larsen, I. Deloncle, S. Péru, F. Zeiser, P.T. Greenlees, B.V. Kheswa, K. Auranen, D.L. Bleuel, D.M. Cox, L. Crespo Campo, F. Giacoppo, A. Görgen, T. Grahn, M. Guttormsen, T.W. Hagen, L. Harkness-Brennan, K. Hauschild, G. Henning, R.-D. Herzberg, R. Julin, S. Juutinen, T.A. Laplace, M. Leino, J.E. Midtbø, V. Modamio, J. Pakarinen, P. Papadakis, J. Partanen, T. Renstrøm, K. Rezynkina, M. Sandzelius, J. Sarén, C. Scholey, S. Siem, J. Sorri, S. Stolze, J. Uusitalo, Laboratoire de Physique des 2 Infinis Irène Joliot-Curie (IJCLab), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), Département Recherches Subatomiques (DRS-IPHC), Institut Pluridisciplinaire Hubert Curien (IPHC), and Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Nuclear and High Energy Physics, scissors mode, transfermium nuclides, γ-strength function, ddc:530, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], ydinfysiikka
Abstract

Physics letters / B 834, 137479 (2022). doi:10.1016/j.physletb.2022.137479, Published by North-Holland Publ., Amsterdam

Published
2022
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22. Exploration des techniques d'intelligence artificielle pour calibrer les modèles physiques

Author

Sami, Yasser, Pollice, Elliott, Tichtchenko, Emilian, Jonckheere, Matthieu, Richard, Nicolas, Rossi, Carole, Estève, Alain, Rossi, Carole, Équipe Nano-ingénierie et intégration des oxydes métalliques et de leurs interfaces (LAAS-NEO), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT), Équipe Services et Architectures pour Réseaux Avancés (LAAS-SARA), CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), and LAAS - CNRS

Subjects
[PHYS.MPHY]Physics [physics]/Mathematical Physics [math-ph], [PHYS.MPHY] Physics [physics]/Mathematical Physics [math-ph]
Abstract

Rapport des travaux 2022 effectués dans le Laboratoire de recherche correspondant sur L'Instrumentation et les Capteurs Ultra-Rapides (LICUR)

Published
2022

23. Femtosecond Resolution of the Nonballistic Electron Energy Transport in Warm Dense Copper

Author

A. Grolleau, F. Dorchies, N. Jourdain, K. Ta Phuoc, J. Gautier, B. Mahieu, P. Renaudin, V. Recoules, P. Martinez, L. Lecherbourg, CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), Centre d'Etudes Lasers Intenses et Applications (CELIA), Université de Bordeaux (UB)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'optique appliquée (LOA), École Nationale Supérieure de Techniques Avancées (ENSTA Paris)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), and ANR-21-CE30-0013,FemTraXS,Transitions de phases femtoseconde sondées par spectroscopie d'absorption X(2021)

Subjects
[PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], [PHYS.PHYS.PHYS-PLASM-PH]Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph], General Physics and Astronomy, ComputingMilieux_MISCELLANEOUS
Abstract

The ultrafast electron energy transport is investigated in laser-heated warm dense copper in a high flux regime (2.5±0.7×10^{13} W/cm^{2} absorbed). The dynamics of the electron temperature is retrieved from femtosecond time-resolved x-ray absorption near-edge spectroscopy near the Cu L3 edge. A characteristic time of ∼1 ps is observed for the increase in the average temperature in a 100 nm thick sample. Data are well reproduced by two-temperature hydrodynamic simulations, which support energy transport dominated by thermal conduction rather than ballistic electrons.

Published
2021
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24. ln-Situ Optical Characterization of Bulk Optical Glasses Under Proton Exposures

Author

Allanche, Timothé, Morana, Adriana, Paillet, Philippe, Duhamel, Olivier, Lambert, Damien, Hoehr, Cornelia, Bélanger-Champagne, Camille, Trinzcek, Michael, Muller, Cyprien, Ouerdane, Y., Boukenter, Aziz, Girard, Sylvain, Laboratoire Hubert Curien [Saint Etienne] (LHC), Université Jean Monnet [Saint-Étienne] (UJM)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS), CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), TRIUMF [Vancouver], Laboratoire Hubert Curien (LHC), and Institut d'Optique Graduate School (IOGS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS]Physics [physics], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2021

25. Un solveur FETI préconditionné non linéairement pour les formulations sous-structurées des problèmes non linéaires

Author

Negrello, Camille, Gosselet, Pierre, Rey, Christian, CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), Laboratoire de mécanique et technologie (LMT), Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Ecole Normale Supérieure Paris-Saclay (ENS Paris Saclay), Laboratoire de Mécanique, Multiphysique, Multiéchelle - UMR 9013 (LaMcube), Centrale Lille-Université de Lille-Centre National de la Recherche Scientifique (CNRS), and Safran Tech

Subjects
Nonlinear mechanics, MathematicsofComputing_NUMERICALANALYSIS, Parallel processing, [SCCO.COMP]Cognitive science/Computer science, Domain decomposition, [NLIN]Nonlinear Sciences [physics], [SPI.MECA]Engineering Sciences [physics]/Mechanics [physics.med-ph], [INFO.INFO-DC]Computer Science [cs]/Distributed, Parallel, and Cluster Computing [cs.DC], FETI solver, Mathematics::Numerical Analysis, Newton solver
Abstract

International audience; We propose a new nonlinear version of preconditioning, dedicated to nonlinear substructured and condensed formulations with dual approach – i.e. nonlinear analogues to FETI solver. By increasing the importance of local nonlinear operations, this new technique reduces communications between processors throughout the parallel solving process. More, the tangent systems produced at each step still have the exact shape of classically preconditioned linear FETI problems, which makes the tractability of the implementation barely modified. The efficiency of this new preconditioner is demonstrated on two numerical test cases, namely a water diffusion problem and a nonlinear thermal behavior.

Published
2021
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26. Seismic swarms in Tricastin, lower Rhône Valley (France) : review of historical and instrumental seismicity and models

Author

Bollinger, Laurent, Le Dortz, Kristel, Duverger, Clara, Vallage, Amaury, Marin, Sylvie, Leroy, Yves M., Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), SEISTER SAS, France, Résif, École normale supérieure - Paris (ENS-PSL), MALERBA, Solène, CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), and Université Paris sciences et lettres (PSL)

Subjects
Macroseismicity, 010504 meteorology & atmospheric sciences, [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], RESIF, 010502 geochemistry & geophysics, 01 natural sciences, Provence, Sismologie, Seismic swarm, 13. Climate action, Earthquakes, General Earth and Planetary Sciences, [SDU.STU.GP] Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], France, Tricastin, Seismology, 0105 earth and related environmental sciences, General Environmental Science
Abstract

International audience; The Tricastin region in the lower Rhône Valley (France) is affected by an atypical seismic activity characterised by the development of long-lasting and recurrent seismic swarms. Indeed, since the 16th century, hundreds of seismic events sometime associated with underground noises of the explosion have been reported by local inhabitants. However, to date, none of the many scenarios of earthquake generation proposed for the area, involving either tectonics and/or hydrological forcings, appears consensual. To overcome that lack of comprehension, we compile and analyse an 880 seismicevents catalogue derived from both historical macroseismicity and instrumental records. The earthquakes appear to occur at shallow depths similar to those determined below a local network in 2002-2003. We confront to this catalogue models involving hydrological mechanisms, including aquifers elastic loading and karst-drains responses, as well as tectonic mechanisms, including transient aseismic processes and their related effects on the fold hinges or on the local fault planes. Most of the earthquakes are located at short distances from karst drains and fractured fold hinges, possibly affected by transient hydrological changes.

Published
2021
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27. High-order monotone finite-volume schemes for 1D elliptic problems

Author

Blanc, Xavier, Hermeline, Francois, Labourasse, Emmanuel, PATELA, Julie, Laboratoire Jacques-Louis Lions (LJLL (UMR_7598)), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), Laboratoire en Informatique Haute Performance pour le Calcul et la simulation (LIHPC), DAM Île-de-France (DAM/DIF), Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction des Applications Militaires (DAM), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay

Subjects
Elliptic problems, Monotonicity, Finite volume method, MSC: 65N06, 65N08, 65N12, [MATH.MATH-AP]Mathematics [math]/Analysis of PDEs [math.AP], High order, [MATH.MATH-NA]Mathematics [math]/Numerical Analysis [math.NA]
Abstract

When solving numerically an elliptic problem, it is important in most applications that the scheme used preserves the positivity of the solution. When using finite volume schemes on deformed mesh, the question has been solved rather recently. Such schemes are usually (at most) second order convergent, and nonlinear. On the other hand, many high-order schemes have been proposed, that do not ensure positivity of the solution. In this paper we propose a very high-order monotone (that is, positivity preserving) numerical method for elliptic problems in 1D. We prove that this method converges to an arbitrary order and is indeed monotone. We also show how to handle discontinuous sources or diffusion coefficients, while keeping the order of convergence. We assess the new scheme, on several test problems, with arbitrary (regular, distorted, random) meshes.

Published
2021

28. Pulsed X‐Ray Radiation Response of Ultralow Loss Pure‐Silica‐Core Optical Fibers

Author

Jeoffray Vidalot, Emmanuel Marin, Adriana Morana, Marc Gaillardin, Vincenzo De Michele, Cosimo Campanella, Aziz Boukenter, Sylvain Girard, Youcef Ouerdane, Philippe Paillet, Claude Marcandella, Laboratoire Hubert Curien [Saint Etienne] (LHC), Université Jean Monnet [Saint-Étienne] (UJM)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS), CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), CEA, DAM, GRAMAT, Laboratoire Hubert Curien (LHC), Institut d'Optique Graduate School (IOGS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), and CEA - Centre de Gramat

Subjects
Materials science, Optical fiber, 010308 nuclear & particles physics, business.industry, X-ray, 02 engineering and technology, Surfaces and Interfaces, Condensed Matter Physics, 01 natural sciences, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, law.invention, 020210 optoelectronics & photonics, law, 0103 physical sciences, 0202 electrical engineering, electronic engineering, information engineering, Materials Chemistry, Optoelectronics, Electrical and Electronic Engineering, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], business, Radiation response, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2021
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29. Photobleaching Effect on the Radiation‐Induced Attenuation of an Ultralow Loss Optical Fiber at Telecommunication Wavelengths

Author

Cosimo Campanella, Jeoffray Vidalot, Vincenzo De Michele, Aziz Boukenter, Sylvain Girard, Philippe Paillet, Emmanuel Marin, Adriana Morana, Youcef Ouerdane, Laboratoire Hubert Curien (LHC), Institut d'Optique Graduate School (IOGS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), Laboratoire Hubert Curien [Saint Etienne] (LHC), and Université Jean Monnet [Saint-Étienne] (UJM)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS)

Subjects
Optical fiber, Materials science, 010308 nuclear & particles physics, business.industry, Attenuation, Radiation induced, 02 engineering and technology, Surfaces and Interfaces, Condensed Matter Physics, 01 natural sciences, Photobleaching, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, law.invention, Wavelength, 020210 optoelectronics & photonics, law, 0103 physical sciences, 0202 electrical engineering, electronic engineering, information engineering, Materials Chemistry, Optoelectronics, Electrical and Electronic Engineering, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], business, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2021
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30. Extensive characterization of Marshak waves observed at the LIL laser facility

Author

C. Courtois, R. Gisbert, O. Breton, S. Darbon, J. Fariaut, O. Henry, D. Raffestin, C. Reverdin, G. Soullie, B. Villette, and CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF)

Subjects
[PHYS]Physics [physics], Condensed Matter Physics
Abstract

We detail results of an experiment performed at the Ligne d'Intégration Laser facility aimed at studying supersonic and diffusive radiation front propagation in low-density SiO2 aerogel (20 and 40 mg/cm3) enclosed in a gold tube, driven by thermal emission from a laser-heated spherical gold cavity. The evolution of the front is studied continuously by measuring its self-emission with a 1D (one-dimensional) time-resolved soft x-ray imager. Measurement is performed along (through a 200- μm-wide observation slit) and at the exit of the tube giving access to the dynamics and the curvature of the front. Experimental results are then compared successfully to results from the 3D (three-dimensional) radiation hydrodynamics code TROLL, which shows that if continuous tracking of the front position is accessible with this experimental scheme, measurement of its maximum radiation temperature is on the contrary affected by radiation closure of the observation slit. 3D simulations also indicate that this effect can even be worsened if one includes pointing errors of the x-ray imager. Radiation temperature along the tube was then inferred by combining results from the imager to a wall shock breakout time measurement using a velocity interferometer system for any reflector and results from a broadband x-ray spectrometer used to determine the temperature at the exit of the tube. A decrease in the radiation temperature along the tube is observed, the decrease being more important for the higher SiO2 aerogel density.

Published
2022
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31. Pulsed X-ray Source Dosimetry Based On Radioluminescent Nitrogen Optical Fiber

Author

Vidalot, Jeoffray, Campanella, Cosimo, Marcandella, Claude, Duhamel, Olivier, Morana, Adriana, Boukenter, Aziz, Ouerdane, Y., Girard, Sylvain, Paillet, Philippe, Laboratoire Hubert Curien [Saint Etienne] (LHC), Université Jean Monnet [Saint-Étienne] (UJM)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS), CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), Laboratoire Hubert Curien (LHC), and Institut d'Optique Graduate School (IOGS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS]Physics [physics], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2021

32. Orogenic Collapse and Stress Adjustments Revealed by an Intense Seismic Swarm Following the 2015 Gorkha Earthquake in Nepal

Author

Lok Bijaya Adhikari, Laurent Bollinger, Jérôme Vergne, Sophie Lambotte, Kristel Chanard, Marine Laporte, Lily Li, Bharat P. Koirala, Mukunda Bhattarai, Chintan Timsina, Nabina Bishwokarma, Nicolas Wendling-Vazquez, Frédéric Girault, Frédéric Perrier, Institut de Physique du Globe de Paris (IPGP), Institut national des sciences de l'Univers (INSU - CNRS)-IPG PARIS-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), Institut Terre Environnement Strasbourg (ITES), École Nationale du Génie de l'Eau et de l'Environnement de Strasbourg (ENGEES)-Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique du Globe de Paris (IPGP (UMR_7154)), and Institut national des sciences de l'Univers (INSU - CNRS)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)

Subjects
010504 meteorology & atmospheric sciences, Science, Swarm behaviour, Magnitude (mathematics), Slip (materials science), 010502 geochemistry & geophysics, 01 natural sciences, relocation, aftershock, seismic swarm, Gorkha earthquake, 13. Climate action, [SDU]Sciences of the Universe [physics], medicine, General Earth and Planetary Sciences, himalaya, seismicity and tectonics, Fluid migration, medicine.symptom, Geology, Aftershock, Seismology, Collapse (medical), 0105 earth and related environmental sciences
Abstract

The April 25, 2015 Mw 7.9 Gorkha earthquake in Nepal was characterized by a peak slip of several meters and persisting aftershocks. We report here that, in addition, a dense seismic swarm initiated abruptly in August 2017 at the western edge of the afterslip region, below the high Himalchuli-Manaslu range culminating at 8156 m, a region seismically inactive during the past 35 years. Over 6500 events were recorded by the Nepal National Seismological Network with local magnitude ranging between 1.8 and 3.7 until November 2017. This swarm was reactivated between April and July 2018, with about 10 times less events than in 2017, and in 2019 with only sporadic events. The relocation of swarm earthquakes using proximal temporary stations ascertains a shallow depth of hypocenters between the surface and 20 km depth in the High Himalayan Crystalline slab. This swarm reveals an intriguing localized interplay between orogenic collapse and stress adjustments, involving possibly CO2-rich fluid migration, more likely post-seismic slip and seasonal enhancements.

Published
2021
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33. The July 20, 2017 Mw = 6.6 Bodrum-Kos Earthquake, Southeast Aegean Sea: Contribution of the Tsunami Modeling to the Assessment of the Fault Parameters

Author

Philippe Heinrich, Audrey Gailler, Athanassios Ganas, Pierre Briole, Louise Cordrie, Laboratoire de géologie de l'ENS (LGENS), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Institut de Physique du Globe de Paris (IPGP (UMR_7154)), Institut national des sciences de l'Univers (INSU - CNRS)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), and National Observatory of Athens (NOA)

Subjects
geography, geography.geographical_feature_category, Geodetic datum, Magnitude (mathematics), [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Slip (materials science), Fault (geology), 010502 geochemistry & geophysics, 01 natural sciences, Mean difference, Geophysics, 13. Climate action, Geochemistry and Petrology, South east, Bathymetry, 14. Life underwater, Source model, Seismology, Geology, [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences
Abstract

The South East Aegean Sea is seismically active with crustal and intermediate-depth earthquakes of magnitude that can exceed the magnitude Mw = 7. On July 20, 2017, a shallow normal faulting Mw = 6.6 earthquake occurred in the Gulf of Gokova, 10 km away from the cities of Kos and Bodrum. A tsunami hit the coasts of Turkey and Kos Island with waves of up to 2 m that damaged several harbors. Based on the field surveys and the tide-gauge records of Bodrum, Syros and Kos harbors, we performed tsunami simulations to constrain the source and analyze the North v/s South-dipping solutions for the fault plane. Depending on the source model, the simulations show different height distributions which provide complementary constrains on the source parameters, helping the characterization of the fault plane. The comparison between our maximum wave heights models and the field data favor the North-dipping fault scenario. When using only the constraint of the Bodrum tide-gauge, our models lead to a source with a 0.7 m fault slip, incompatible with the slip inferred from geodesy. When using the constrain from neighboring coastal wave heights and run-up recovered during field surveys, the best fit is obtained with a 2 m fault slip scenario consistent with the geodetic models. There is a 0.25 m mean difference between observed and synthetic water heights that could be due to the unaccuracy of the bathymetry data.

Published
2021
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34. An off-lattice kinetic Monte Carlo kernel guided by topological and geometrical analysis to bridge accurate ab-initio calculations and large scale simulations

Author

Gunde, Miha, Salles, Nicolas, Richard, Nicolas, Hémeryck, Anne, Martin-Samos, Layla, Équipe Modélisation Multi-niveaux des Matériaux (LAAS-M3), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT), CNR Istituto Officina dei Materiali (IOM), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), and Hemeryck, Anne

Subjects
[PHYS]Physics [physics], [PHYS] Physics [physics]
Abstract

International audience; The kMC method is traditionally used on-lattice, where a property such as atomic type, is assigned to each point of a fixed lattice. The evolution is then a series of changes on the property of lattice points, called events given by a catalog, that occur with a probability associated with reaction barriers. In the more general case, ie object-kMC1, the concept of event is not restricted to single atom transformations. Due to limitations imposed by the lattice, these approaches often fall short for complex system evolution, such as ion diffusion in amorphous/disordered solids, collective transformations, or events with specific environmental dependency. In2, to accelerate molecular dynamics through OKMC, off-lattice capabilities have been implemented by using on-the-fly search of events, enabled by graph theory and empirical potential. We propose an alternative approach that uses graph theory and geometric shape-matching to build a catalog from ab-initio results, and take into account the symmetries of events which allows their execution in any direction, without need of lattice. Our proposed atom-resolved off-lattice kMC can treat a large variety of systems. Some examples will be shown emphasizing the different capabilities.

Published
2021

35. Hybrid high-order methods for the acoustic wave equation in the time domain

Author

Burman, Erik, Duran, Omar, Ern, Alexandre, Department of Mathematics (UCL London), University College of London [London] (UCL), Centre d'Enseignement et de Recherche en Mathématiques et Calcul Scientifique (CERMICS), École des Ponts ParisTech (ENPC), Simulation for the Environment: Reliable and Efficient Numerical Algorithms (SERENA), Inria de Paris, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), The authors would like to thank CEA/DAM for partial financial support. Erik Burman was partially supported by the EPSRC grants EP/P01576X/1and EP/P012434/1., and The authors would like to thank CEA/DAM for partial financial support. EB was partially supported by the EPSRC grants EP/P01576X/1and EP/P012434/1.

Subjects
65M22, 65M12, 65M60, 35L05, Runge-Kutta scheme, Mathematics Subjects Classification.65M22, 65M12, 65M60, 35L05, wave equation, Hybrid high-order methods, [MATH.MATH-NA]Mathematics [math]/Numerical Analysis [math.NA], Newmark scheme
Abstract

We devise hybrid-high order (HHO) methods for the acoustic wave equation in the time domain. We first consider the second-order formulation in time. Using the New-mark scheme for the temporal discretization, we show that the resulting HHO-Newmark scheme is energy-conservative, and this scheme is also amenable to static condensation at each time-step. We then consider the formulation of the acoustic wave equation as a first-order system together with singly-diagonally implicit and explicit Runge-Kutta (SDIRK and ERK) schemes. HHO-SDIRK schemes are amenable to static condensation at each time-step. For HHO-ERK schemes, the use of the mixed-order formulation, where the polynomial degree of the cell unknowns is one order higher than that of the face unknowns, is key to benefit from the explicit structure of the scheme. Numerical results on test cases with analytical solutions show that the methods can deliver optimal convergence rates for smooth solutions of order $O(h^{k+1})$ in the $H^1$-norm and of order $O(h^{k+2})$ in the $L^2$-norm. Moreover, test cases on wave propagation in heterogeneous media indicate the benefits of using high-order methods.

Published
2021

36. L'action transversale sismicité RESIF : un outil pour améliorer la diffusion des produits de la sismicité française

Author

Didier Bertil, Ludmila Provost, Gilles Mazet-Roux, Christophe Sira, Samuel Auclair, Frédéric Masson, Marc Grunberg, B. Hernandez, Antoine Schlupp, Sophie Lambotte, Jean-Marie Saurel, Ecole et Observatoire des Sciences de la Terre (EOST), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut Terre Environnement Strasbourg (ITES), École Nationale du Génie de l'Eau et de l'Environnement de Strasbourg (ENGEES)-Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Institut de Physique du Globe de Paris (IPGP), Institut national des sciences de l'Univers (INSU - CNRS)-IPG PARIS-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Centre d'Études de Limeil-Valenton (CEA-DAM), Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), PSE-ENV/SCAN/BERSSIN, Bureau d'évaluation des risques sismiques pour la sûreté des installations (IRSN/PSE-ENV/SCAN/BERSSIN), Service de caractérisation des sites et des aléas naturels (IRSN/PSE-ENV/SCAN), Institut de Radioprotection et de Sûreté Nucléaire (IRSN)-Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Institut de Physique du Globe de Paris (IPGP (UMR_7154)), and Institut national des sciences de l'Univers (INSU - CNRS)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)

Subjects
bulletins and catalogues, 010504 meteorology & atmospheric sciences, Geodetic network, business.industry, [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], shakemap, Distribution (economics), Geodetic datum, Sismicité, macroseismicity data, Induced seismicity, 010502 geochemistry & geophysics, Résif, 01 natural sciences, Sismologie, Geophysics, France, business, French seismicity, Seismology, Geology, 0105 earth and related environmental sciences
Abstract

International audience; In recent years, the French seismological, geodetic and gravimetric community has been structured within RESIF (French seismological and geodetic network). In addition to instrumental developments, RESIF has structured the work on French seismicity (metropolitan and overseas) within the RESIF transverse seismicity action (ATS). The purpose of this article is to present the ATS and the way it is structured to propose to the community different products: seismicity bulletin and catalogue, historical and instrumental macroseismicity data, shakemaps. The places where these products can be found are indicated, as well as the way they are realized and the improvements in progress for a better realization and availability. The link with EPOS (European plate observing system) is also underlined.; Ces dernières années, la communauté sismologique, géodésique et gravimétrique française s'est structurée au sein de RESIF (Réseau sismologique et géodésique français). Outre les développements instrumentaux, RESIF a structuré les travaux sur la sismicité française (métropole et outre-mer) au sein de l'Action transverse sismicité (ATS) de RESIF. L'objet de cet article est de présenter l'ATS et la manière dont elle est structurée pour proposer à la communauté différents produits : bulletin et catalogue de sismicité, données historiques et instrumentales de macrosismicité, shakemaps. Les endroits où ces produits peuvent être trouvés sont indiqués, ainsi que la façon dont ils sont réalisés et les améliorations en cours pour une meilleure réalisation et disponibilité. Le lien avec EPOS (European plate observing system) est également souligné.

Published
2021
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37. Clusters of Defects as a Possible Origin of Random Telegraph Signal in Imager Devices: a DFT based Study

Author

L. Martin Samos, Nicolas Richard, P.L. Julliard, Denis Rideau, Anne Hémeryck, A. LeRoch, Vincent Goiffon, Filadelfo Cristiano, Antoine Jay, S. de Gironcoli, Commissariat à l'Energie Atomique et aux énergies alternatives - CEA (FRANCE), Centre National de la Recherche Scientifique - CNRS (FRANCE), Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE), Institut National des Sciences Appliquées de Toulouse - INSA (FRANCE), Institut Supérieur de l'Aéronautique et de l'Espace - ISAE-SUPAERO (FRANCE), STMicroelectronics (FRANCE), Université Toulouse III - Paul Sabatier - UT3 (FRANCE), Université Toulouse - Jean Jaurès - UT2J (FRANCE), Université Toulouse 1 Capitole - UT1 (FRANCE), CNR Istituto Officina dei Materiali - IOM (Rome, Italy), Équipe Modélisation Multi-niveaux des Matériaux (LAAS-M3), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, Équipe Matériaux et Procédés pour la Nanoélectronique (LAAS-MPN), STMicroelectronics [Crolles] (ST-CROLLES), Institut Supérieur de l'Aéronautique et de l'Espace (ISAE-SUPAERO), CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), CNR Istituto Officina dei Materiali (IOM), Consiglio Nazionale delle Ricerche [Roma] (CNR), Scuola Internazionale Superiore di Studi Avanzati / International School for Advanced Studies (SISSA / ISAS), European Project: 871813,H2020-EU.2.1.1. - INDUSTRIAL LEADERSHIP - Leadership in enabling and industrial technologies - Information and Communication Technologies (ICT) ,MUNDFAB (2020), Centre d'Études de Limeil-Valenton (CEA-DAM), Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT), and National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR)

Subjects
Band gap, Radiation effects, 02 engineering and technology, 01 natural sciences, Signal, Settore FIS/03 - Fisica della Materia, Atomic measurements, Metastability, 0103 physical sciences, cross sections, Cluster (physics), Traitement du signal et de l'image, Electronics, defects, 010302 applied physics, Physics, [PHYS]Physics [physics], Modulation, Semiconductor device measurement, business.industry, defects electronic states, Time measurement, 021001 nanoscience & nanotechnology, Discrete Fourier transforms, Computational physics, Semiconductor, Dark current, random telegraph signal, (SISPAD)(SISPAD)Dark current, 0210 nano-technology, business, electronic states, Switches
Abstract

International audience; The origin of the random telegraph signal (RTS) observed in semiconductors-based electronic devices is still subject to debates. In this work, by means of atomistic simulations, typical clusters of defects as could be obtained after irradiation or implantation are studied as a possible cause for RTS. It is shown that: (i) a cluster of defects is highly metastable, (ii) it introduces several electronic states in the band gap, (iii) it has an electronic cross section much higher than the one of point defects. These three points can simultaneously explain why an electronhole generation rate can switch with time, while respecting the experimental measurement.

Published
2021
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38. Mesure de très haute précision des neutrons de fission du plutonium 239

Author

Taieb, Julien, Marini, Paola, Benoit, Laurent, Belier, Gilbert, Chatillon, Audrey, Morfouace, Pierre, Étasse, David, Devlin, Mattew, Gomez, J.A., Haight, R.C., Kelly, K. L., O'Donnell, J.M., Schmitt, K. T., Marini, Paola, CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Los Alamos National Laboratory (LANL)

Subjects
[PHYS.NEXP] Physics [physics]/Nuclear Experiment [nucl-ex], [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2021

39. Réponse rapide au tremblement de terre Mw 4.9 du 11 novembre 2019 au Teil, dans la basse vallée du Rhône, en France

Author

Christophe Voisin, Michalis Foumelis, Léo Marconato, Emmanuelle Nayman, Martijn van den Ende, Florent Brenguier, Jérémy Billant, Marcello de Michele, Huihui Weng, Christophe Maron, Isabelle Douste-Bacque, Sébastien Hok, Raphaël Grandin, Axel Jung, Julie Régnier, Stéphane Guillot, A. Mordret, Romain Jolivet, Stéphane Baize, Matthieu Ferry, Fabrice Peix, Laurence Audin, Tiziano Giampietro, Jean-Paul Ampuero, Andrea Walpersdorf, Marianne Métois, Diane Rivet, Maxime Godano, Bérénice Froment, Michel Pernoud, Gauthier Guerin, Coralie Aubert, Antoine Schlupp, Martin Vallée, Valérie Sellier, Anne Socquet, Andy Combey, Emeline Maufroy, Catherine Pequegnat, Anne Deschamps, Antoine Mercier, Christian Sue, Marine Menager, Christophe Sira, Philippe Langlaude, Claudio Satriano, Olivier Cavalié, Diego Mercerat, Anne Paul, Estelle Hannouz, Céline Gélis, Philippe Vernant, Etienne Bertrand, Christophe Larroque, Pierre Briole, Chao Liang, Philippe Hervé Leloup, Rihab Sassi, Jean-François Ritz, Bertrand Delouis, Emmanuel Mathot, Mickael Langlais, Jérôme Chèze, David Wolynieck, Mathieu Causse, Ludmila Provost, Cécile Cornou, Marc Schaming, Xavier Martin, Rémi Dretzen, Itzhak Lior, Mohamed Chlieh, Elias el Haber, Elise Beck, Jean-Robert Grasso, Elif Oral, Benjamin Vial, Kevin Manchuel, Hervé Jomard, Pascal Allemand, Philippe Grandjean, Véronique Bertrand, Françoise Courboulex, Anthony Sladen, Didier Brunel, Aurélie Guilhem Trilla, Ildut Pondaven, Daniel Mata, Cécile Lasserre, Marc Grunberg, Alain Hernandez, Institut des Sciences de la Terre (ISTerre), Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Gustave Eiffel-Université Grenoble Alpes (UGA), Géoazur (GEOAZUR 7329), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud]), Institut de Recherche pour le Développement (IRD), Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Géosciences Montpellier, Institut national des sciences de l'Univers (INSU - CNRS)-Université de Montpellier (UM)-Université des Antilles (UA)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique du Globe de Paris (IPGP), Institut national des sciences de l'Univers (INSU - CNRS)-IPG PARIS-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement [Lyon] (LGL-TPE), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon), Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement (Cerema), EDF (EDF), Terradue (ITALY), Institut de physique du globe de Strasbourg (IPGS), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Ecole et Observatoire des Sciences de la Terre (EOST), Laboratoire de géologie de l'ENS (LGENS), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire Chrono-environnement - CNRS - UBFC (UMR 6249) (LCE), Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Pacte, Laboratoire de sciences sociales (PACTE), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Sciences Po Grenoble - Institut d'études politiques de Grenoble (IEPG ), Université Grenoble Alpes (UGA), Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Grenoble Alpes (UGA)-Université Gustave Eiffel-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry]), Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud]), Laboratoire de géologie de l'ENS (LGE), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA), Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement - Equipe-projet MOUVGS (Cerema Equipe-projet MOUVGS), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), UMS THETA (terre, homme, environnement, temps, astronomie) (UMS 3245) (OSU-THETA), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Bourgogne (UB)-Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Institut de Physique du Globe de Paris, École normale supérieure - Lyon (ENS Lyon), CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique du Globe de Paris (IPGP (UMR_7154)), Institut national des sciences de l'Univers (INSU - CNRS)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), Terradue Srl, Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Sciences Po Grenoble - Institut d'études politiques de Grenoble (IEPG), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Laboratoire Chrono-environnement (UMR 6249) (LCE), Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud]), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire des Mécanismes et Transfert en Géologie (LMTG), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), PSE-ENV/SCAN/BERSSIN, ANR-15-CE31-0015,AlpArray-FR,Voir et comprendre les Alpes en 3D, de la croûte au manteau(2015), and ANR-11-EQPX-0040,RESIF-CORE,Réseau sismologique et géodésique français : l'équipement fondamental(2011)

Subjects
bepress|Physical Sciences and Mathematics, Earthquake, 010504 meteorology & atmospheric sciences, Magnitude (mathematics), bepress|Physical Sciences and Mathematics|Earth Sciences, Context (language use), Induced seismicity, Fault (geology), 010502 geochemistry & geophysics, InSAR interferometry, 01 natural sciences, bepress|Physical Sciences and Mathematics|Earth Sciences|Geophysics and Seismology, Le Teil Earthquake, Interferometric synthetic aperture radar, Surface rupture, Tremblement de terre, Le Teil, Rapid response, Aftershock, Seismology, Rhône valley, General Environmental Science, 0105 earth and related environmental sciences, [SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics, geography, geography.geographical_feature_category, Le Teil earthquake, Rhône valley, Seismic sequence, Post-seismic, Surface rupture, InSAR interferometry, RESIF, seismic sequence, Massif, post-seismic, Tectonics, Sismologie, [SDU]Sciences of the Universe [physics], General Earth and Planetary Sciences, Geology, Séisme
Abstract

International audience; On November 11, 2019, a Mw 4.9 earthquake hit the region close to Montelimar (lower Rhône Valley, France), on the eastern margin of the Massif Central close to the external part of the Alps. Occuring in a moderate seismicity area, this earthquake is remarkable for its very shallow focal depth (between 1 and 3 km), its magnitude, and the moderate to large damages it produced in several villages. InSAR interferograms indicated a shallow rupture about 4 km long reaching the surface and the reactivation of the ancient NE–SW La Rouvière normal fault in reverse faulting in agreement with the present-day E–W compressional tectonics. The peculiarity of this earthquake together with a poor coverage of the epicentral region by permanent seismological and geodetic stations triggered the mobilisation of the French post-seismic unit and the broad French scientific community from various institutions, with the deployment of geophysical instruments (seismological and geodesic stations), geological field surveys, and field evaluation of the intensity of the earthquake. Within 7 days after the mainshock, 47 seismological stations were deployed in the epicentral area to improve the Le Teil aftershocks locations relative to the French permanent seismological network (RESIF), monitor the temporal and spatial evolution of microearthquakes close to the fault plane and temporal evolution of the seismic response of 3 damaged historical buildings, and to study suspected site effects and their influence in the distribution of seismic damage. This seismological dataset, completed by data owned by different institutions, was integrated in a homogeneous archive and distributed through FDSN web services by the RESIF data center. This dataset, together with observations of surface rupture evidences, geologic, geodetic and satellite data, will help to unravel the causes and rupture mechanism of this earthquake, and contribute to account in seismic hazard assessment for earthquakes along the major regional Cévenne fault system in a context of present-day compressional tectonics.

Published
2020
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40. Microwave Transmission of Pressure Sensor Signal Through Explosive Fireballs

Author

Patrick Pons, A. Coustou, M Lavayssiere, Alexandre Lefrançois, J. Luc, Mathieu Chalnot, Hervé Aubert, Équipe MIcro et Nanosystèmes pour les Communications sans fil (LAAS-MINC), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT), Service Instrumentation Conception Caractérisation (LAAS-I2C), CEA / DAM (CEA), CEA (CEA/DAM), LICUR, Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), and Université Fédérale Toulouse Midi-Pyrénées

Subjects
Materials science, Explosive material, Astrophysics::High Energy Astrophysical Phenomena, Acoustics, 020208 electrical & electronic engineering, 020206 networking & telecommunications, 02 engineering and technology, Microwave transmission, Pressure sensor, Signal, [SPI.ELEC]Engineering Sciences [physics]/Electromagnetism, Transmission (telecommunications), Modulation, Distortion, 0202 electrical engineering, electronic engineering, information engineering, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, Nuclear Experiment, Microwave
Abstract

International audience; In this paper, we use microwaves for wirelessly transmitting the pressure signal delivered by sensors placed inside high explosive fireballs. It is demonstrated that the modulation of a microwave carrier frequency by pressure signal may be transmitted through fireballs without significant distortion, spectral filtering and attenuation of pressure signal. For experimental validation purpose, we show that the proposed wireless measurement of the pressure variation inside fireballs is in very good agreement with that obtained from a wired transmission, even if aluminized explosives create fireballs

Published
2020
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41. Landslide tsunamis: Comparison between depth-averaged and Navier–Stokes models

Author

Alexandre Paris, Stéphane Abadie, Philippe Heinrich, CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), Laboratoire des Sciences de l'Ingénieur Appliquées à la Mécanique et au génie Electrique (SIAME), and Université de Pau et des Pays de l'Adour (UPPA)

Subjects
Environmental Engineering, Turbulence, Reynolds number, Ocean Engineering, Geometry, Landslide, Laminar flow, Viscous liquid, Physics::Geophysics, Physics::Fluid Dynamics, [SPI]Engineering Sciences [physics], Viscosity, symbols.namesake, Free surface, [SDE]Environmental Sciences, Subaerial, symbols, ComputingMilieux_MISCELLANEOUS, Geology
Abstract

Two approaches are proposed to simulate tsunamis generated by granular landslides: a depth-averaged model, AVALANCHE, and laminar Navier–Stokes simulations using the OpenFOAM model. Both models are validated against two 2D benchmarks, a subaerial and a submerged one involving a triangle initial slide shape. In both models, the landslide is defined as a viscous fluid flowing downslope. Except in the first instants, both models can reproduce either the landslide behavior or the generated first water waves but cannot reproduce simultaneously both the landslide and the water surface. There is an overlap in the optimal viscosity range between both models. Sensitivity studies are carried out by varying the slope angle and the landslide submergence for the subaerial benchmark. The largest waves are obtained for initial landslide position close to the free surface. The height of the generated waves increases linearly with the slope angle and the landslide Reynolds number in the depth-averaged model. The relationships are more complex in the Navier–Stokes model. For low slide Reynolds numbers and with an initial slide close to the free surface, both models produce similar waves. Nine additional cases are performed with a k − e turbulence closure model and varying the submergence and the slope angle.

Published
2021
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42. The mantle transition zone dynamics as revealed through seismic anisotropy

Author

G. Burgos, Jean-Paul Montagner, Yann Capdeville, Eric Beucler, Antoine Mocquet, Institut de Physique du Globe de Paris (IPG Paris), CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), Laboratoire de Planétologie et Géodynamique [UMR 6112] (LPG), Université d'Angers (UA)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), and Université de Nantes (UN)-Université de Nantes (UN)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Seismic anisotropy, Geophysics, Water transport, Mantle convection, Subduction, [SDU]Sciences of the Universe [physics], Transition zone, Slab, Petrology, Anisotropy, Geology, Mantle (geology), Earth-Surface Processes
Abstract

The mantle transition zone (MTZ) of the Earth lies between 410 and ∼1000 km in depth and has a key role in mantle convection processes. In particular, the discontinuity at 660 km and its associated endothermic mineralogical transformation can slow or inhibit the passage of matter between the upper and lower mantle. The MTZ thus acts as a boundary layer within the mantle. The depth variations of radial and azimuthal seismic anisotropies enable the detection of boundary layers within the mantle. However, the 3D imaging is difficult due to the lack of sensitivity of surface waves of fundamental modes, and the poor global coverage of this depth range by body-wave data. We present a new 3D general anisotropy model (both radial and azimuthal anisotropies) of the mantle down to 1200 km in depth using surface-wave overtone datasets. We find that there is little seismic anisotropy in most of the MTZ, except below subduction zones around the Pacific Ocean and, more surprisingly, in a large area beneath eastern Eurasia where the Pacific subducting plate is stagnant. Seismic anisotropy is usually associated with intense deformation processes but also possibly to water transportation or to fine layering. This significant anisotropy in this part of MTZ might reveal a large water ‘reservoir’ associated with hydrous minerals or a strong stratification. It reflects a complex history beneath central Asia, where the Tethys, Izanagi and Pacific plates appear to have strongly interacted during the last 100 My, having subducted in orthogonal directions under the Asian continent, with the Tethys plate descending into the lower mantle, and the Izanagi plate remaining stagnant in the MTZ. The Asian continent is the only region in the world where subducting slabs originating from different plates can interact. This unique slab distribution might explain why some plates descend while others remain in the lower transition zone.

Published
2021
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45. The transition and mixing efficiency of the turbulent Faraday instability

Author

Briard, Antoine, Gréa, Benoît-Joseph, Gostiaux, Louis, Centre de Mathématiques et de Leurs Applications (CMLA), École normale supérieure - Cachan (ENS Cachan)-Centre National de la Recherche Scientifique (CNRS), CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), Laboratoire de Mecanique des Fluides et d'Acoustique (LMFA), École Centrale de Lyon (ECL), Université de Lyon-Université de Lyon-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), and Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph]
Abstract

International audience

Published
2019

46. The competition between turbulent and molecular diffusion in plasma mixing layers under compression

Author

Viciconte, Giovanni, Gréa, Benoît-Joseph, Fabien, Godeferd, CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), Laboratoire de Mecanique des Fluides et d'Acoustique (LMFA), École Centrale de Lyon (ECL), Université de Lyon-Université de Lyon-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), and Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph]
Abstract

International audience

Published
2019

47. Experimental study of turbulent Faraday instability in miscible fluids

Author

Gostiaux, Louis, Gréa, Benoît-Joseph, Briard, Antoine, Laboratoire de Mecanique des Fluides et d'Acoustique (LMFA), École Centrale de Lyon (ECL), Université de Lyon-Université de Lyon-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), and École normale supérieure - Cachan (ENS Cachan)

Subjects
[PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph]
Abstract

International audience

Published
2019

48. Development of a new operational urban Lagrangian dispersion model for emergency response

Author

Slimani, Mehdi, Soulhac, Lionel, Lamaison, Guillevic, Armand, Patrick, Patryl, Luc, CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), Laboratoire de Mecanique des Fluides et d'Acoustique (LMFA), École Centrale de Lyon (ECL), Université de Lyon-Université de Lyon-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), and Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph]
Abstract

International audience

Published
2019

49. High power continuous wave laser heating of graphite in a high temperature range up to 3800 K

Author

E. Lescoute, Y. Pontillon, T. Vidal, Laurent Gallais, Jean-Luc Rullier, Institut FRESNEL (FRESNEL), Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS), CEA DAM ILE-DE-FRANCE - Bruyères-le-Châtel [Arpajon] (CEA DAM IDF), CEA Cadarache, Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA-CESTA), and Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Aix Marseille Université (AMU)

Subjects
010302 applied physics, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], Materials science, Nuclear engineering, General Physics and Astronomy, 02 engineering and technology, Atmospheric temperature range, 021001 nanoscience & nanotechnology, Laser, 7. Clean energy, 01 natural sciences, law.invention, Thermal conductivity, law, 0103 physical sciences, Emissivity, Continuous wave, Vacuum chamber, Graphite, 0210 nano-technology, ComputingMilieux_MISCELLANEOUS, Pyrometer
Abstract

International audience; As graphite is an important material for several applications, the evaluation of its properties at very high temperatures is of major importance. Conducting studies at temperatures >2800 K is, however, very challenging, and the amount of available data in the literature is, therefore, very limited. This paper presents a methodology that compares experimental data with simulation results following a progressive increase of the temperature range investigated. The study was conducted on a commercial polycrystalline graphite produced by sintering (EDM-3 from POCO) under high power continuous laser heating (kW ytterbium at a wavelength of 1080 nm). Experiments were done inside a vacuum chamber equipped with pyrometers and cameras allowing fine monitoring of the temperature of the samples. A 3D numerical model has been developed based on the finite element method to analyze the experimental results. The evolution of the thermal and optical properties of EDM-3 with temperature is required for correctly modeling laser/material interactions. By running a sequential comparison of calculation with a dedicated experiment, we achieve better knowledge of such properties. From this study, we obtain estimations of the evolution of thermal conductivity, emissivity, and evaporation rate up to 3800 K of amorphous graphite.

Published
2021
Full Text
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