Author: "Klaus Hornung" - Searchworks@Jio Institute Digital Library Search Results

Your search keyword '"Klaus Hornung"' showing total 36 results

Start Over Author "Klaus Hornung"

36 results on '"Klaus Hornung"'

1. Measured mechanical, optical and electrical properties of dust partciles collected in the coma of comet 67/P

Author: Martin Hilchenbach, Oliver Stenzel, and Klaus Hornung
Abstract: During the ESA ROSETTA science mission to comet 67P/Churyumov-Gerasimenko, the dust particle analysing instrument COSIMA sampled dust in the size range from a few um to mm equivalent diameter in the inner coma of the comet. The particles were analysed in-situ with an optical microscope and a secondary ion mass spectrometer. The dust particles were collected on porous gold black surfaces with relative low impact velocity and the break up or fragmentation due to impact as well as by mechanical and/or electrical means have been studied. We summarize the results and conclusions on the measured mechanical, optical and electrical parameters such as porosity, material strength, reflectance, electrical conductivity and relative permittivity of the dust particles.
Published: 2023

2. Kometenstaub unter dem Mikroskop

Author: Jochen Kissel, Martin Hilchenbach, Andreas Koch, and Klaus Hornung
Subjects: Physics, 010504 meteorology & atmospheric sciences, 0103 physical sciences, 010303 astronomy & astrophysics, 01 natural sciences, 0105 earth and related environmental sciences
Published: 2018

3. Optical properties of cometary particles collected by COSIMA: Assessing the differences between microscopic and macroscopic scales

Author: Sihane Merouane, Martin Hilchenbach, Rita Schulz, Jouni Rynö, Klaus Hornung, Mathieu Vincendon, Cecile Engrand, Jochen Kissel, Yves Langevin, Institut d'astrophysique spatiale (IAS), and Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, Range (particle radiation), 010504 meteorology & atmospheric sciences, biology, Comet, Phase (waves), [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Astronomy and Astrophysics, Scale (descriptive set theory), Astrophysics, biology.organism_classification, 01 natural sciences, Reflectivity, Lower half, Wavelength, Space and Planetary Science, 0103 physical sciences, Osiris, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences
Abstract: International audience; The COSIMA mass spectrometer on-board Rosetta was equipped with an optical microscope, Cosiscope, which identified several 10,000 cometary particles collected on targets exposed during the orbital phase around the nucleus of comet 67P Churyumov-Gerasimenko. The median value of reflectance factors evaluated from Cosiscope images for large collected particles (~10.5% (Langevin et al., 2017), lies above the range of reflectance observed by the OSIRIS camera at a similar wavelength (5-7%, (Fornasier et al., 2015), but at much larger scales (a few 10 cm instead of a few 10 μm). In order to better understand this discrepancy, the assumptions underlying the derivation of reflectance factors have been reassessed using laboratory measurements of COSIMA targets and analogs of cometary particles. The approach of Langevin et al. is validated, but we consider that the uncertainty on reflectance factors was conservative. The reflectance factors are likely to lie in the lower half of the previously estimated range, which reduces (but does not eliminate) the discrepancy with OSIRIS albedos. The remaining discrepancy can be attributed primarily to the difference in scale (factor 10,000 in pixel size between COSIMA and OSIRIS)
Published: 2019

4. Evolution of the physical properties of dust and cometary dust activity from 67P/Churyumov–Gerasimenko measured in situ by Rosetta/COSIMA

Author: Klaus Hornung, Rita Schulz, J. Kissel, B. Zaprudin, Martin Hilchenbach, Jouni Rynö, Henning Fischer, Sihane Merouane, Yves Langevin, Eva Maria Mellado, Nicolas Altobelli, and Oliver Stenzel
Subjects: In situ, Physics, 010504 meteorology & atmospheric sciences, Space and Planetary Science, 0103 physical sciences, Astronomy, Astronomy and Astrophysics, 010303 astronomy & astrophysics, 01 natural sciences, 0105 earth and related environmental sciences, Astrobiology
Published: 2017

5. Evidence of sub-surface energy storage in comet 67P from the outburst of 2016 July 03

Author: M. A. Barucci, Eberhard Grün, Giampiero Naletto, Ivano Bertini, M. De Cecco, Pedro Hasselmann, S. Mottola, Wing-Huen Ip, Laurent Jorda, Bernhard Geiger, Xian Shi, Maurizio Pajola, Jouni Rynö, Gabriele Cremonese, Oliver Stenzel, J. J. Lopez Moreno, J. L. Bertaux, J. Kissel, S. Höfner, M. F. A'Hearn, Olivier Groussin, Martin Hilchenbach, B. Zaprudin, Steve Boudreault, V. Da Deppo, Alessandra Rotundi, Ludmilla Kolokolova, Dennis Bodewits, Philippe Lamy, Jessica Agarwal, Marc Hofmann, Paul D. Feldman, Horst Uwe Keller, Stefano Debei, Sihane Merouane, J. Wm. Parker, Monica Lazzarin, Stubbe F. Hviid, Michael Küppers, Stavro Ivanovski, Cesare Barbieri, Jean-Baptiste Vincent, Francesco Marzari, Detlef Koschny, Yves Langevin, Sonia Fornasier, N. Oklay, L. M. Lara, Jakob Deller, Zhong-Yi Lin, A. Koch, Andrew J. Steffl, R. Rodrigo, Björn Davidsson, J.-R. Kramm, Carsten Güttler, E. Kührt, Cecilia Tubiana, Klaus Hornung, P. J. Gutierrez, Stephen C. Lowry, Jörg Knollenberg, Holger Sierks, Henning Fischer, Marco Fulle, V. Della Corte, A. Gicquel, Harold A. Weaver, Nicolas Thomas, Lori M. Feaga, Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), Max-Planck-Gesellschaft, Dipartimento di Scienze e Tecnologie [Napoli] (DIST), Università degli Studi di Napoli 'Parthenope' = University of Naples (PARTHENOPE), Department of Physics and Astronomy [Baltimore], Johns Hopkins University (JHU), European Space Astronomy Centre (ESAC), Agence Spatiale Européenne = European Space Agency (ESA), Centro di Ateneo di Studi e Attività Spaziali 'Giuseppe Colombo' (CISAS), Università degli Studi di Padova = University of Padua (Unipd), Department of Astronomy [College Park], University of Maryland [College Park], University of Maryland System-University of Maryland System, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-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 Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Kernphysik (MPIK), Laboratory for Atmospheric and Space Physics [Boulder] (LASP), University of Colorado [Boulder], Istituto di Astrofisica Spaziale e Fisica cosmica - Roma (IASF-Roma), Istituto Nazionale di Astrofisica (INAF), NASA Ames Research Center (ARC), Department of Space Studies [Boulder], Southwest Research Institute [Boulder] (SwRI), Physikalisches Institut [Bern], Universität Bern [Bern] (UNIBE), Dipartimento di Fisica e Astronomia 'Galileo Galilei', PLANETO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), INAF - Osservatorio Astronomico di Padova (OAPD), CNR Institute for Photonics and Nanotechnologies (IFN), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Department of Industrial Engineering [Padova], INAF - Osservatorio Astronomico di Trieste (OAT), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Instituto de Astrofísica de Andalucía (IAA), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Universität der Bundeswehr München [Neubiberg], DLR Institut für Planetenforschung, Deutsches Zentrum für Luft- und Raumfahrt [Berlin] (DLR), Institute of Astronomy [Taiwan] (IANCU), National Central University [Taiwan] (NCU), Institut für Geophysik und Extraterrestrische Physik [Braunschweig] (IGEP), Technische Universität Braunschweig = Technical University of Braunschweig [Braunschweig], von Hoerner und Sulger GmbH, European Space Research and Technology Centre (ESTEC), Research and Scientific Support Department, ESTEC (RSSD), Agence Spatiale Européenne = European Space Agency (ESA)-Agence Spatiale Européenne = European Space Agency (ESA), Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Centre for Astrophysics and Planetary Science [Canterbury] (CAPS), University of Kent [Canterbury], CNR Istituto di Fotonica e Nanotecnologie [Padova] (IFN), Centro de Astrobiologia [Madrid] (CAB), Instituto Nacional de Técnica Aeroespacial (INTA)-Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), International Space Science Institute [Bern] (ISSI), Finnish Meteorological Institute (FMI), Johns Hopkins University Applied Physics Laboratory [Laurel, MD] (APL), Tuorla Observatory, University of Turku, Lowry, S.C., ITA, FRA, DEU, ESP, Centre National de la Recherche Scientifique (France), German Centre for Air and Space Travel, Agenzia Spaziale Italiana, Swedish National Space Board, Ministerio de Economía y Competitividad (España), European Space Agency, Max-Planck-Institut für Sonnensystemforschung (MPS), Universita degli studi di Napoli 'Parthenope' [Napoli], European Space Agency (ESA), Universita degli Studi di Padova, Universität Bern [Bern], Sorbonne Université (SU)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Consiglio Nazionale delle Ricerche [Roma] (CNR), California Institute of Technology (CALTECH)-NASA, European Space Agency (ESA)-European Space Agency (ESA), and Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Asteroiden und Kometen, Solid state: refractory, Acceleration of particles, 010504 meteorology & atmospheric sciences, 01 natural sciences, law.invention, Astrobiology, Scattering, individual: 67P/Churyumov-Gerasimenko [Comets], law, Rosetta, 0103 physical sciences, Surface change, Astrophysics::Solar and Stellar Astrophysics, Sunrise, OSIRIS, Solid state: volatile, Crystallization, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, Comets: individual: 67P/Churyumov-Gerasimenko, [PHYS]Physics [physics], Physics, ta115, 520 Astronomy, volatile [Solid state], general [Comets], Astronomy and Astrophysics, Solar illumination, 620 Engineering, Surface energy, Amorphous solid, Comets: general, On board, 13. Climate action, Space and Planetary Science, acceleration of particles, scattering, solid state: refractory, solid state: volatile, comets: general, comets: individual: 67P/Churyumov-Gerasimenko, Physics::Space Physics, Sublimation (phase transition), QB651, Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], refractory [Solid state]
Abstract: On 2016 July 03, several instruments onboard ESA's Rosetta spacecraft detected signs of an outburst event on comet 67P, at a heliocentric distance of 3.32 au from the Sun, outbound from perihelion. We here report on the inferred properties of the ejected dust and the surface change at the site of the outburst. The activity coincided with the local sunrise and continued over a time interval of 14-68 min. It left a 10-m-sized icy patch on the surface. The ejected material comprised refractory grains of several hundred microns in size, and sub-micron-sized water ice grains. The high dust mass production rate is incompatible with the free sublimation of crystalline water ice under solar illumination as the only acceleration process. Additional energy stored near the surface must have increased the gas density. We suggest a pressurized sub-surface gas reservoir, or the crystallization of amorphous water ice as possible causes.© 2015 The Authors., The support of the national funding agencies of Germany (DLR, grant 50 QP 1302), France (CNES), Austria, Finland and the ESA Technical Directorate is gratefully acknowledged.
Published: 2017

6. Synthesis of the morphological description of cometary dust at comet 67P/Churyumov-Gerasimenko

Author: Martin Hilchenbach, Klaus Hornung, Alberto Flandes, Jérémie Lasue, Anny Chantal Levasseur-Regourd, Giovanna Rinaldi, Stavro Ivanovski, Marco Fulle, Harald Krüger, Andrea Longobardo, Dominique Bockelée-Morvan, Dennis Bodewits, Stefano Mottola, Yves Langevin, C. Güttler, Gianrico Filacchione, Ivano Bertini, G. P. Tozzi, Holger Sierks, Jürgen Blum, J. Agarwal, Fabrizio Capaccioni, Giampiero Naletto, Thurid Mannel, F. Moreno, Alessandra Rotundi, Imre Tóth, Sihane Merouane, V. Della Corte, John Paquette, Cecilia Tubiana, Max Planck Institute for Solar System Research (MPS), Max-Planck-Gesellschaft, Max-Planck-Institut für Sonnensystemforschung (MPS), Space Research Institute of Austrian Academy of Sciences (IWF), Austrian Academy of Sciences (OeAW), Institute of Physics [Graz], Karl-Franzens-Universität [Graz, Autriche], Istituto di Astrofisica e Planetologia Spaziali - INAF (IAPS), Istituto Nazionale di Astrofisica (INAF), Dipartimento di Scienze e Tecnologie [Napoli] (DIST), Universita degli studi di Napoli 'Parthenope' [Napoli], INAF - Osservatorio Astronomico di Trieste (OAT), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), 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 Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Institut de recherche en astrophysique et planétologie (IRAP), Institut national des sciences de l'Univers (INSU - CNRS)-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), PLANETO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Sorbonne Université (SU)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Institut für Geophysik und Extraterrestrische Physik [Braunschweig] (IGEP), Technische Universität Braunschweig = Technical University of Braunschweig [Braunschweig], Centro di Ateneo di Studi e Attività Spaziali 'Giuseppe Colombo' (CISAS), Universita degli Studi di Padova, Dipartimento di Fisica e Astronomia 'Galileo Galilei', CNR Istituto di Fotonica e Nanotecnologie [Milano] (IFN), Consiglio Nazionale delle Ricerche [Roma] (CNR), Instituto de Geofisica [Mexico], Universidad Nacional Autónoma de México (UNAM), Instituto de Astrofísica de Andalucía (IAA), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Department of Physics [Auburn], Auburn University (AU), INAF - Osservatorio Astrofisico di Arcetri (OAA), Universität der Bundeswehr München [Neubiberg], Institut d'astrophysique spatiale (IAS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Konkoly Observatory, Research Centre for Astronomy and Earth Sciences [Budapest], Hungarian Academy of Sciences (MTA)-Hungarian Academy of Sciences (MTA), DLR Institut für Planetenforschung, Deutsches Zentrum für Luft- und Raumfahrt [Berlin] (DLR), Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), Karl-Franzens-Universität Graz, Università degli Studi di Napoli 'Parthenope' = University of Naples (PARTHENOPE), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-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), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Università degli Studi di Padova = University of Padua (Unipd), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), Universidad Nacional Autónoma de México = National Autonomous University of Mexico (UNAM), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), University of Graz, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), IMPEC - LATMOS, Technische Universität Braunschweig [Braunschweig], Consejo Superior de Investigaciones Científicas [Spain] (CSIC), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), ITA, FRA, DEU, and ESP
Subjects: Asteroiden und Kometen, instruments [space vehicles], 010504 meteorology & atmospheric sciences, comets: general – comets: individual: 67P/Churyumov-Gerasimenko – space vehicles: instruments, Computer science, Comet, Individual, 01 natural sciences, Space exploration, Astrobiology, Interplanetary dust cloud, individual: 67P/Churyumov-Gerasimenko [Comets], 0103 physical sciences, 67P/Churyumov-Gerasimenko - space vehicles, Comets, General - comets, Instruments, Instrumentation (computer programming), space vehicles: instruments, 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, [PHYS]Physics [physics], Comets: individual: 67P/Churyumov-Gerasimenko, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], general [Comets], Astronomy and Astrophysics, Common framework, Comets: general, [SDU]Sciences of the Universe [physics], Space and Planetary Science
Abstract: Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Open Access funding provided by Max Planck Society., Before Rosetta, the space missions Giotto and Stardust shaped our view on cometary dust, supported by plentiful data from Earth based observations and interplanetary dust particles collected in the Earth's atmosphere. The Rosetta mission at comet 67P/Churyumov-Gerasimenko was equipped with a multitude of instruments designed to study cometary dust. While an abundant amount of data was presented in several individual papers, many focused on a dedicated measurement or topic. Different instruments, methods, and data sources provide different measurement parameters and potentially introduce different biases. This can be an advantage if the complementary aspect of such a complex data set can be exploited. However, it also poses a challenge in the comparison of results in the first place. The aim of this work therefore is to summarize dust results from Rosetta and before. We establish a simple classification as a common framework for intercomparison. This classification is based on the dust particle structure, porosity, and strength and also on its size. Depending on the instrumentation, these are not direct measurement parameters, but we chose them because they were the most reliable for deriving our model. The proposed classification has proved helpful in the Rosetta dust community, and we offer it here also for a broader context. In this manner, we hope to better identify synergies between different instruments and methods in the future.© C. Güttler et al. 2019
Published: 2019

7. Electrical properties of cometary dust particles derived from line shapes of TOF-SIMS spectra measured by the ROSETTA/COSIMA instrument

Author: Klaus Hornung, Hervé Cottin, John Paquette, Paola Modica, Harry Lehto, Kurt Varmuza, Rita Schulz, Oliver Stenzel, Martin Hilchenbach, Christelle Briois, Nicolas Fray, Yves Langevin, Laurent Thirkell, Donia Baklouti, Sihane Merouane, Jouni Rynö, Anais Bardyn, Sandra Siljeström, Henning Fischer, Cécile Engrand, Johan Silen, Eva Maria Mellado, Jochen Kissel, Andreas Koch, Institut für Strömungsmechanik und Aerodynamik (LRT-7), Universität der Bundeswehr München [Neubiberg] = Bundeswehr University, Max-Planck-Institut für Sonnensystemforschung (MPS), Max-Planck-Gesellschaft, Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA (UMR_7583)), Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Climate and Environmental Physics [Bern] (CEP), Physikalisches Institut [Bern], Universität Bern [Bern]-Universität Bern [Bern], Laboratoire de Physiogénomique / NeuroTranscriptomes et Paléogénétique (LPG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-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, PSL Research University (PSL)-PSL Research University (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Finnish Meteorological Institute Observation Services, Finnish Meteorological Institute (FMI), European Space Research and Technology Centre (ESTEC), European Space Agency (ESA), Geophysical Laboratory, Carnegie Institution of Washington, 5251 Broad Branch Road, Washington DC 20015, USA, Tuorla Observatory, University of Turku, Technische Universität Wien (TU Wien), University of Salzburg, Universität der Bundeswehr München [Neubiberg], Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), Carnegie Institution for Science [Washington], 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), ESA Scientific Support Office, RISE Research Institutes of Sweden, Vienna University of Technology (TU Wien), Carnegie Institution for Science, Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, and PSL Research University (PSL)-PSL Research University (PSL)-Centre National d’Études Spatiales [Paris] (CNES)
Subjects: Permittivity, Secondary ion mass spectrometry, Materials science, 010504 meteorology & atmospheric sciences, Electric properties, Comet, Analytical chemistry, 67p/churyumov-gerasimenko, Electrical permittivity, 7. Clean energy, 01 natural sciences, Spectral line, Specific resistivities, Negative ions, Ion, Time of flight, Electrical resistivity and conductivity, 0103 physical sciences, Naturvetenskap, Rosetta mission, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, Line (formation), Cometary dust, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Sample charging, Astronomy and Astrophysics, Dust, Time-of-flight mass spectra, Secondary ion mass spectrometers, [PHYS.PHYS.PHYS-SPACE-PH]Physics [physics]/Physics [physics]/Space Physics [physics.space-ph], Cometary dusts, 13. Climate action, Space and Planetary Science, [SDU]Sciences of the Universe [physics], Mass spectrum, Electrical properties, Cometary dust Rosetta mission Electrical properties Time-of-flight mass spectra Sample charging, Natural Sciences, Mass spectrometers
Abstract: Between Aug. 2014 and Sept. 2016, while ESA's cornerstone mission Rosetta was operating in the vicinity of the nucleus and in the coma of comet 67P/Churyumov-Gerasimenko, the COSIMA instrument collected a large number of dust particles with diameters up to a millimeter. Positive or negative ions were detected by a time-of-flight secondary ion mass spectrometer (TOF-SIMS) and the composition of selected particles was deduced. Many of the negative ion mass spectra show, besides mass peaks at the correct position, an additional, extended contribution at the lower mass side caused by partial charging of the dust. This effect, usually avoided in SIMS applications, can in our case be used to obtain information on the electrical properties of the collected cometary dust particles, such as the specific resistivity (ρr>1.2⋅1010Ωm) and the real part of the relative electrical permittivity (εr0.8). Funding details: Austrian Science Fund, FWF, P26871-N20; Funding details: Centre National d’Etudes Spatiales, CNES; Funding details: Deutsches Zentrum für Luft- und Raumfahrt, DLR, 50 QP 1801; Funding text 1: COSIMA was built by a consortium led by the Max-Planck-Institut für Extraterrestrische Physik, Garching, Germany in collaboration with Laboratoire de Physique et Chimie de l’Environnement et de l’Espace, Orléans, France, Institut d’Astrophysique Spatiale, CNRS/Université Paris Sud, Orsay, France, Finnish Meteorological Institute, Helsinki, Finland, Universität Wuppertal, Wuppertal, Germany, von Hoerner und Sulger GmbH, Schwetzingen, Germany, Universität der Bundeswehr München, Neubiberg, Germany, Institut für Physik, Forschungszentrum Seibersdorf, Seibersdorf, Austria, Institut für Weltraumforschung, Österreichische Akademie der Wissenschaften, Graz, Austria and is lead by the Max-Planck-Institut für Sonnensystemforschung, Göttingen, Germany. The support of the national funding agencies of Germany ( DLR , grant 50 QP 1801 ), France ( CNES ), Austria ( FWF , grant P26871-N20 ), Finland and the ESA Technical Directorate is gratefully acknowledged. We thank the Rosetta Science Ground Segment at ESAC, the Rosetta Mission Operations Centre at ESOC and the Rosetta Project at ESTEC for their outstanding work enabling the science return of the Rosetta Mission. Appendix A
Published: 2019

8. Mechanical and electrostatic experiments with dust particles collected in the inner coma of comet 67P by COSIMA onboard Rosetta

Author: Jochen Kissel, Anais Bardyn, Christelle Briois, Donia Baklouti, Martin Hilchenbach, Kurt Varmuza, Rita Schulz, John Paquette, W. Steiger, Nicolas Altobelli, Nicolas Fray, Sandra Siljeström, Andreas Koch, R. Thomas, Paola Modica, Johan Silen, Klaus Hornung, Henning Fischer, Oliver Stenzel, Yves Langevin, B. Zaprudin, Eva Maria Mellado, Léna Le Roy, Laurent Thirkell, H. Höfner, H. Henkel, Gerhard Haerendel, Hervé Cottin, Jouni Rynö, Sihane Merouane, Cécile Engrand, Harry Lehto, Klaus Torkar, Institut d'astrophysique spatiale ( IAS ), Université Paris-Sud - Paris 11 ( UP11 ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace ( LPC2E ), Centre National de la Recherche Scientifique ( CNRS ) -Université d'Orléans ( UO ) -Institut national des sciences de l'Univers ( INSU - CNRS ), Laboratoire inter-universitaire des systèmes atmosphèriques ( LISA ), Institut national des sciences de l'Univers ( INSU - CNRS ) -Université Paris Diderot - Paris 7 ( UPD7 ) -Université Paris-Est Créteil Val-de-Marne - Paris 12 ( UPEC UP12 ) -Centre National de la Recherche Scientifique ( CNRS ), Centre de Sciences Nucléaires et de Sciences de la Matière ( CSNSM ), Université Paris-Sud - Paris 11 ( UP11 ) -Institut National de Physique Nucléaire et de Physique des Particules du CNRS ( IN2P3 ) -Centre National de la Recherche Scientifique ( CNRS ), Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-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)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National d’Études Spatiales [Paris] (CNES), Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA (UMR_7583)), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Centre National d’Études Spatiales [Paris] (CNES), Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-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)-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), and Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Institut national des sciences de l'Univers (INSU - CNRS)
Subjects: Physics, ta115, 010504 meteorology & atmospheric sciences, Ion beam, General Mathematics, [ PHYS.ASTR ] Physics [physics]/Astrophysics [astro-ph], Dust particles, General Engineering, General Physics and Astronomy, Astrophysics, 01 natural sciences, Astrobiology, Ion, Secondary ion mass spectrometry, Low speed, 13. Climate action, Agglomerate, [SDU]Sciences of the Universe [physics], Comet nucleus, 0103 physical sciences, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], 010303 astronomy & astrophysics, 0105 earth and related environmental sciences
Abstract: The in situ cometary dust particle instrument COSIMA (COmetary Secondary Ion Mass Analyser) onboard ESA's Rosetta mission has collected about 31 000 dust particles in the inner coma of comet 67P/Churyumov–Gerasimenko since August 2014. The particles are identified by optical microscope imaging and analysed by time-of-flight secondary ion mass spectrometry. After dust particle collection by low speed impact on metal targets, the collected particle morphology points towards four families of cometary dust particles. COSIMA is an in situ laboratory that operates remotely controlled next to the comet nucleus. The particles can be further manipulated within the instrument by mechanical and electrostatic means after their collection by impact. The particles are stored above 0°C in the instrument and the experiments are carried out on the refractory, ice-free matter of the captured cometary dust particles. An interesting particle morphology class, the compact particles, is not fragmented on impact. One of these particles was mechanically pressed and thereby crushed into large fragments. The particles are good electrical insulators and transform into rubble pile agglomerates by the application of an energetic indium ion beam during the secondary ion mass spectrometry analysis. This article is part of the themed issue ‘Cometary science after Rosetta’.
Published: 2017

9. Nitrogen-to-carbon atomic ratio measured by COSIMA in the particles of comet 67P/Churyumov–Gerasimenko

Author: Christelle Briois, Rita Schulz, Sandra Siljeström, B. Zaprudin, John Paquette, Paola Modica, Jouni Rynö, Henning Fischer, Martin Hilchenbach, Anais Bardyn, Oliver Stenzel, François-Régis Orthous-Daunay, Harry Lehto, Johan Silen, Cécile Engrand, Laurent Thirkell, Robin Isnard, Kurt Varmuza, Eva Maria Mellado, Yves Langevin, Donia Baklouti, Klaus Hornung, Léna Le Roy, Hervé Cottin, Sihane Merouane, J. Kissel, Nicolas Fray, Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA (UMR_7583)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Paris (UP)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12), 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)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National d’Études Spatiales [Paris] (CNES), Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Max-Planck-Institut für Sonnensystemforschung (MPS), Max-Planck-Gesellschaft, Laboratoire Imagerie et Systèmes d'Acquisition (LISA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), University of Turku, Universität Bern [Bern], Universität der Bundeswehr München [Neubiberg], Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Finnish Meteorological Institute (FMI), RISE Research Institutes of Sweden, Vienna University of Technology (TU Wien), ANR-10-LABX-0047,ESEP,Space explorations of Planetary Environments(2010), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), 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), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Universität Bern [Bern] (UNIBE), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), and Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS)
Subjects: Astrochemistry, Comet, Analytical chemistry, 010502 geochemistry & geophysics, 01 natural sciences, meteorites, Interplanetary dust cloud, Chondrite, 0103 physical sciences, meteors, meteoroids, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, Gerasimenko, Physics, Range (particle radiation), ta115, Meteoroid, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], astrochemistry, comets: general, Astronomy and Astrophysics, Meteorite, 13. Climate action, Space and Planetary Science, comets: individual: 67P/Churyumov, space vehicles, Atomic ratio
Abstract: International audience; The COmetary Secondary Ion Mass Analyzer (COSIMA) on board the Rosetta mission has analysed numerous cometary dust particles collected at very low velocities (a few m s(-1)) in the environment of comet 67P/Churyumov-Gerasimenko (hereafter 67P). In these particles, carbon and nitrogen are expected mainly to be part of the organic matter. We have measured the nitrogen-to-carbon (N/C) atomic ratio of 27 cometary particles. It ranges from 0.018 to 0.06 with an averaged value of 0.035 +/- 0.011. This is compatible with the measurements of the particles of comet 1P/Halley and is in the lower range of the values measured in comet 81P/Wild 2 particles brought back to Earth by the Stardust mission. Moreover, the averaged value found in 67P particles is also similar to the one found in the insoluble organic matter extracted from CM, CI and CR carbonaceous chondrites and to the bulk values measured in most interplanetary dust particles and micrometeorites. The close agreement of the N/C atomic ratio in all these objects indicates that their organic matters share some similarities and could have a similar chemical origin. Furthermore, compared to the abundances of all the detected elements in the particles of 67P and to the elemental solar abundances, the nitrogen is depleted in the particles and the nucleus of 67P as was previously inferred also for comet 1P/Halley. This nitrogen depletion could constrain the formation scenarios of cometary nuclei.
Published: 2017

10. Carbon-rich dust in comet 67P/Churyumov-Gerasimenko measured by COSIMA/Rosetta

Author: Martin Hilchenbach, Donia Baklouti, John Paquette, Anais Bardyn, Hervé Cottin, Rita Schulz, J. Kissel, Klaus Hornung, Laurent Thirkell, B. Zaprudin, Jouni Rynö, Cécile Engrand, Nicolas Fray, Henning Fischer, François-Régis Orthous-Daunay, Harry Lehto, Sihane Merouane, Kurt Varmuza, Johan Silen, Robin Isnard, Léna Le Roy, N. Ligier, Christelle Briois, Yves Langevin, Paola Modica, Oliver Stenzel, Laboratoire Imagerie et Systèmes d'Acquisition (LISA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), 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)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National d’Études Spatiales [Paris] (CNES), Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Sonnensystemforschung (MPS), Max-Planck-Gesellschaft, Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Universität der Bundeswehr München [Neubiberg], Université Paris-Est (UPE), Tuorla Observatory, University of Turku, Center for Space and Habitability (CSH), University of Bern, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Finnish Meteorological Institute Observation Services, Finnish Meteorological Institute (FMI), European Space Research and Technology Centre (ESTEC), European Space Agency (ESA), Vienna University of Technology (TU Wien), ANR-10-LABX-0047,ESEP,Space explorations of Planetary Environments(2010), 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), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Agence Spatiale Européenne = European Space Agency (ESA)
Subjects: Astrochemistry, 010504 meteorology & atmospheric sciences, Comet, chemistry.chemical_element, Mass spectrometry, 01 natural sciences, Astrobiology, Ion, Jupiter, 0103 physical sciences, Organic matter, space vehicles: instruments, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, chemistry.chemical_classification, Physics, ta115, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], astrochemistry, comets: general, Astronomy and Astrophysics, Accretion (astrophysics), chemistry, 13. Climate action, Space and Planetary Science, techniques: miscellaneous, comets: individual: 67P/Churyumov-Gerasimenko, Carbon
Abstract: International audience; Cometary ices are rich in CO2, CO and organic volatile compounds, but the carbon content of cometary dust was only measured for the Oort Cloud comet 1P/Halley, during its flyby in 1986. The COmetary Secondary Ion Mass Analyzer (COSIMA)/Rosetta mass spectrometer analysed dust particles with sizes ranging from 50 to 1000 mu m, collected over 2 yr, from 67P/Churyumov-Gerasimenko (67P), a Jupiter family comet. Here, we report 67P dust composition focusing on the elements C and O. It has a high carbon content (atomic C/Si = 5.5(-1.2)(+1.4) on average) close to the solar value and comparable to the 1P/Halley data. From COSIMA measurements, we conclude that 67P particles are made of nearly 50 per cent organic matter in mass, mixed with mineral phases that are mostly anhydrous. The whole composition, rich in carbon and non-hydrated minerals, points to a primitive matter that likely preserved its initial characteristics since the comet accretion in the outer regions of the protoplanetary disc.
Published: 2017

11. On the application of a linear time-of-flight mass spectrometer for the investigation of hypervelocity impacts of micron and sub-micron sized dust particles

Author: Sascha Kempf, L. E. O'Brien, Mihaly Horanyi, Zoltan Sternovsky, Ralf Srama, A. Collette, K. Drake, Anna Mocker, Klaus Hornung, Tobin Munsat, and Eberhard Grün
Subjects: Shock wave, Physics, Astronomy and Astrophysics, Astrophysics, Plasma, Radiation, Computational physics, Characterization (materials science), Space and Planetary Science, Hypervelocity, State of matter, Ejecta, Astrophysics::Galaxy Astrophysics, Cosmic dust
Abstract: Impact physics plays an important role in a variety of fields such as investigation of matter at extreme pressures and temperatures, shock waves in solid bodies or planetology and cosmic dust research. The processes of interest are the generation of impact plasma, neutrals, secondary ejecta, and electromagnetic (EM) radiation. The generation of charge during impacts provides one of the most sensitive methods for the detection and characterization of dust particles in space. To relate the measured values resulting from hypervelocity impact experiments with the impact parameters (speed, mass, composition) a comprehensive set of experiments is needed with well known experimental conditions, and a wide variety of diagnostic tools. For such experiments dust particles are accelerated to hypervelocity speeds in the laboratory with an electrostatic accelerator. In the present contribution, linear time-of flight ( TOF ) mass spectrometry is used to investigate the thermodynamical properties, e.g. the velocity distribution, of the ions within an impact plasma. Furthermore, the dependence of the plasma properties on the impact parameters is studied for different dust and target material combinations to investigate the constraints for the validity of impact ionization models. These studies provide new insights into the physics of hypervelocity impacts and the short timescale high-pressure states of matter, they also lead to the development of new and optimization of existing instrument concepts for the detection and characterization of cosmic dust in space.
Published: 2013

12. A first assessment of the strength of cometary particles collected in-situ by the COSIMA instrument onboard ROSETTA

Author: Klaus Hornung, Sihane Merouane, Martin Hilchenbach, Yves Langevin, Eva Maria Mellado, Vincenzo Della Corte, Jochen Kissel, Cecile Engrand, Rita Schulz, Jouni Ryno, Johan Silen, null the COSIMA team, Institut für Strömungsmechanik und Aerodynamik (LRT-7), Universität der Bundeswehr München [Neubiberg], Max-Planck-Institut für Sonnensystemforschung (MPS), Max-Planck-Gesellschaft, Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Istituto di Astrofisica e Planetologia Spaziali - INAF (IAPS), Istituto Nazionale di Astrofisica (INAF), Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM AS), Université Paris-Saclay-Univ. Paris-Sud-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), ESA Scientific Support Office, European Space Agency (ESA), Finnish Meteorological Institute Observation Services, Finnish Meteorological Institute (FMI), 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), Italian Space Agency within the ASI-INAF agreements I/032/05/0 and I/024/12/0., COSIMA was built by a consortium led by the Max-Planck-Institut für Extraterrestrische Physik, Garching, Germany in collaboration with Laboratoire de Physique et Chimie de l'Environnement et de l'Espace, Orléans, France, Institut d'Astrophysique Spatiale, CNRS/Université Paris Sud, Orsay, France, Finnish Meteorological Institute, Helsinki, Finland, Universität Wuppertal, Wuppertal, Germany, von Hoerner und Sulger GmbH, Schwetzingen, Germany, Universität der Bundeswehr, Neubiberg, Germany, Institut für Physik, Forschungszentrum Seibersdorf, Seibersdorf, Austria, Institut für Weltraumforschung, Österreichische Akademie der Wissenschaften, Graz, Austria and is led by the Max-Planck-Institut für Sonnensystemforschung, Göttingen, Germany., ITA, FRA, and DEU
Subjects: In situ, Physics, Cometary dust, ta115, 010504 meteorology & atmospheric sciences, Spacecraft, Impact fragmentation, Mechanical strength, Rosetta mission, Astronomy and Astrophysics, Space and Planetary Science, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], business.industry, Dust particles, Comet, Astronomy, 01 natural sciences, Fragment size, 0103 physical sciences, Mass analyzer, business, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences
Abstract: COSIMA was built by a consortium led by the Max-Planck-Institut für Extraterrestrische Physik, Garching, Germany in collaboration with Laboratoire de Physique et Chimie de l'Environnement et de l'Espace, Orléans, France, Institut d'Astrophysique Spatiale, CNRS/Université Paris Sud, Orsay, France, Finnish Meteorological Institute, Helsinki, Finland, Universität Wuppertal, Wuppertal, Germany, von Hoerner und Sulger GmbH, Schwetzingen, Germany, Universität der Bundeswehr, Neubiberg, Germany, Institut für Physik, Forschungszentrum Seibersdorf, Seibersdorf, Austria, Institut für Weltraumforschung, Österreichische Akademie der Wissenschaften, Graz, Austria and is led by the Max-Planck-Institut für Sonnensystemforschung, Göttingen, Germany. The support of the national funding agencies of Germany (DLR, Grant 50 QP 1302), France (CNES), Austria, Finland and the ESA Technical Directorate; International audience; Soon after the arrival of the ROSETTA spacecraft at Comet 67/P Churyumov-Gerasimenko the onboard instrument COSIMA (“Cometary Secondary Ion Mass Analyzer”) collected a large number of cometary dust particles on targets from gold black of thickness between 10 and 30 μm. Inspection by its camera subsystem revealed that many of them consist of smaller units of typically some tens of micrometers in size. The collection process left the smaller dust particles in an essentially unaltered state whereas most particles larger than about 100 μm got fragmented into smaller pieces. Using the observed fragment size distributions, the present paper includes a first assessment of the strength for those dust particles that were disrupted upon impact.
Published: 2016

13. Dust particle flux and size distribution in the coma of 67P/Churyumov-Gerasimenko measured in situ by the COSIMA instrument on board Rosetta

Author: Martin Hilchenbach, N. Ligier, Marco Fulle, Yves Langevin, Jouni Rynö, Rita Schulz, Klaus Hornung, Sihane Merouane, Nicolas Altobelli, B. Zaprudin, Henning Fischer, Oliver Stenzel, Johan Silen, Alessandra Rotundi, Jochen Kissel, V. Della Corte, ITA, FRA, and DEU
Subjects: In situ, Physics, Comets: individual: 67P/Churyumov-Gerasimenko, Astronomy and Astrophysics, Space and Planetary Science, 010504 meteorology & atmospheric sciences, Astrophysics, 01 natural sciences, Power law, Ion, On board, Interplanetary dust cloud, 0103 physical sciences, Millimeter, Porosity, 010303 astronomy & astrophysics, Stratosphere, 0105 earth and related environmental sciences
Abstract: Context. The COmetary Secondary Ion Mass Analyzer (COSIMA) on board Rosetta is dedicated to the collection and compositional analysis of the dust particles in the coma of 67P/Churyumov-Gerasimenko (67P). Aims: Investigation of the physical properties of the dust particles collected along the comet trajectory around the Sun starting at a heliocentric distance of 3.5 AU. Methods: The flux, size distribution, and morphology of the dust particles collected in the vicinity of the nucleus of comet 67P were measured with a daily to weekly time resolution. Results: The particles collected by COSIMA can be classified according to their morphology into two main types: compact particles and porous aggregates. In low-resolution images, the porous material appears similar to the chondritic-porous interplanetary dust particles collected in Earth's stratosphere in terms of texture. We show that this porous material represents 75% in volume and 50% in number of the large dust particles collected by COSIMA. Compact particles have typical sizes from a few tens of microns to a few hundreds of microns, while porous aggregates can be as large as a millimeter. The particles are not collected as a continuous flow but appear in bursts. This could be due to limited time resolution and/or fragmentation either in the collection funnel or few meters away from the spacecraft. The average collection rate of dust particles as a function of nucleo-centric distance shows that, at high phase angle, the dust flux follows a 1/d2comet law, excluding fragmentation of the dust particles along their journey to the spacecraft. At low phase angle, the dust flux is much more dispersed compared to the 1/d2comet law but cannot be explained by fragmentation of the particles along their trajectory since their velocity, indirectly deduced from the COSIMA data, does not support such a phenomenon. The cumulative size distribution of particles larger than 150 μm follows a power law close to r- 0.8 ± 0.1, confirming measurements made by another Rosetta dust instrument Grain Impact Analyser and Dust Accumulator (GIADA). The cumulative size distribution of particles between 30 μm and 150 μm has a power index of -1.9 ± 0.3. The excess of dust in the 10-100 μm range in comparison to the 100 μm-1 mm range together with no evidence for fragmentation in the inner coma, implies that these particles could have been released or fragmented at the nucleus right after lift-off of larger particles. Below 30 μm, particles exhibit a flat size distribution. We interprete this knee in the size distribution at small sizes as the consequence of strong binding forces between the sub-constitutents. For aggregates smaller than 30 μm, forces stronger than Van-der-Waals forces would be needed to break them apart.
Published: 2016

14. High-molecular-weight organic matter in the particles of comet 67P/Churyumov–Gerasimenko

Author: Harald Krüger, Jochen Kissel, H. Henkel, Anais Bardyn, Albrecht Glasmachers, François-Régis Orthous-Daunay, Hervé Cottin, Elmar K. Jessberger, Eberhard Grün, Harry Lehto, François Raulin, Kirsi Lehto, Kurt Varmuza, Sihane Merouane, Nicolas Fray, H. Höfner, Yves Langevin, Luigi Colangeli, Laurent Thirkell, Kathrin Altwegg, Andreas Koch, Johan Silen, Gerhard Haerendel, Léna Le Roy, Jouni Rynö, Christelle Briois, Paola Modica, Oliver Stenzel, Klaus Torkar, Donia Baklouti, Karl-Peter Wanczek, Martin Hilchenbach, Thomas Stephan, John Paquette, R. Thomas, Rita Schulz, Klaus Hornung, Henning Fischer, Cécile Engrand, W. Steiger, Sandra Siljeström, B. Zaprudin, Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA (UMR_7583)), Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-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), Center for Space and Habitability (CSH), University of Bern, Physikalisches Institut [Bern], Universität Bern [Bern], Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), European Space Research and Technology Centre (ESTEC), European Space Agency (ESA), Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM AS), Université Paris-Saclay-Univ. Paris-Sud-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Climate and Environmental Physics [Bern] (CEP), Universität Bern [Bern]-Universität Bern [Bern], Max-Planck-Institut für Kernphysik (MPIK), Max-Planck-Gesellschaft, Institut für Strömungsmechanik und Aerodynamik (LRT-7), Universität der Bundeswehr München [Neubiberg], Max Planck Institute for Solar System Research (MPS), Tuorla Observatory, University of Turku, Max-Planck-Institut für Sonnensystemforschung (MPS), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Finnish Meteorological Institute Observation Services, Finnish Meteorological Institute (FMI), Department of Chemistry, Materials and Surfaces [Boras], SP Technical Research Institute of Sweden, Department of Geophysical Sciences [Chicago], University of Chicago, Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), Universität Bern [Bern] (UNIBE), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Saclay-Univ. Paris-Sud, Universität Bern [Bern] (UNIBE)-Universität Bern [Bern] (UNIBE), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Institut national des sciences de l'Univers (INSU - CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Centre National d’Études Spatiales [Paris] (CNES), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Laboratoire inter-universitaire des systèmes atmosphèriques ( LISA ), Institut national des sciences de l'Univers ( INSU - CNRS ) -Université Paris Diderot - Paris 7 ( UPD7 ) -Université Paris-Est Créteil Val-de-Marne - Paris 12 ( UPEC UP12 ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace ( LPC2E ), Centre National de la Recherche Scientifique ( CNRS ) -Université d'Orléans ( UO ) -Institut national des sciences de l'Univers ( INSU - CNRS ), Center for Space and Habitability ( CSH ), Institut d'astrophysique spatiale ( IAS ), Université Paris-Sud - Paris 11 ( UP11 ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ), European Space Research and Technology Centre ( ESTEC ), European Space Agency ( ESA ), Centre de Sciences Nucléaires et de Sciences de la Matière ( CSNSM AS ), Université Paris-Saclay-Univ. Paris-Sud-CNRS/IN2P3, Climate and Environmental Physics [Bern], Max-Planck-Institut für Kernphysik ( MPIK ), Institut für Strömungsmechanik und Aerodynamik ( LRT-7 ), Max Planck Institute for Solar System Research ( MPS ), Max-Planck-Institut für Sonnensystemforschung ( MPS ), Institut de Planétologie et d'Astrophysique de Grenoble ( IPAG ), Observatoire des Sciences de l'Univers de Grenoble ( OSUG ), Université Joseph Fourier - Grenoble 1 ( UJF ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Grenoble Alpes ( UGA ) -Université Joseph Fourier - Grenoble 1 ( UJF ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Grenoble Alpes ( UGA ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire Magmas et Volcans ( LMV ), Université Blaise Pascal - Clermont-Ferrand 2 ( UBP ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Université Jean Monnet [Saint-Étienne] ( UJM ) -Centre National de la Recherche Scientifique ( CNRS ), P.O. Box 1870, Nordnes, Institute of Marine Research, Science Faculty, Department Biology, Padualaan 8, Utrecht University [Utrecht], The University of Chicago, Department of the Geophysical Sciences ( THE UNIVERSITY OF CHICAGO ), and The Univerity of Chicago, Department of the Geophysical Sciences
Subjects: chemistry.chemical_classification, Multidisciplinary, ta115, 010504 meteorology & atmospheric sciences, Hydrogen, Comet dust, chemistry.chemical_element, Methods• References• Acknowledgements• Author information• Extended data figures and tables, 01 natural sciences, Astrobiology, Interstellar medium, chemistry, Meteorite, 13. Climate action, [SDU]Sciences of the Universe [physics], Carbonaceous chondrite, 0103 physical sciences, Sublimation (phase transition), Organic matter, Formation and evolution of the Solar System, 010303 astronomy & astrophysics, [ SDU ] Sciences of the Universe [physics], 0105 earth and related environmental sciences
Abstract: International audience; The presence of solid carbonaceous matter in cometary dust was established by the detection of elements such as carbon, hydrogen, oxygen and nitrogen in particles from comet 1P/Halley1, 2. Such matter is generally thought to have originated in the interstellar medium3, but it might have formed in the solar nebula—the cloud of gas and dust that was left over after the Sun formed4. This solid carbonaceous material cannot be observed from Earth, so it has eluded unambiguous characterization5. Many gaseous organic molecules, however, have been observed6, 7, 8, 9; they come mostly from the sublimation of ices at the surface or in the subsurface of cometary nuclei8. These ices could have been formed from material inherited from the interstellar medium that suffered little processing in the solar nebula10. Here we report the in situ detection of solid organic matter in the dust particles emitted by comet 67P/Churyumov–Gerasimenko; the carbon in this organic material is bound in very large macromolecular compounds, analogous to the insoluble organic matter found in the carbonaceous chondrite meteorites11, 12. The organic matter in meteorites might have formed in the interstellar medium and/or the solar nebula, but was almost certainly modified in the meteorites’ parent bodies11. We conclude that the observed cometary carbonaceous solid matter could have the same origin as the meteoritic insoluble organic matter, but suffered less modification before and/or after being incorporated into the comet.
Published: 2016

15. Mass spectrometry of impact fragmented polymers: The role of target properties

Author: Steven P. Armes, Eva Maria Mellado, Klaus Hornung, Ralf Srama, Syuji Fujii, and Jochen Kissel
Subjects: chemistry.chemical_classification, Nanostructure, Materials science, Mechanical Engineering, Aerospace Engineering, Ocean Engineering, Polymer, Polypyrrole, Mass spectrometry, Ion, chemistry.chemical_compound, chemistry, Fragmentation (mass spectrometry), Mechanics of Materials, Chemical physics, Ionization, Automotive Engineering, Mass spectrum, Safety, Risk, Reliability and Quality, Civil and Structural Engineering
Abstract: Sulphur-containing latex micro-particles coated with an ultrathin conductive layer of polypyrrole have been accelerated in a van de Graff accelerator (up to 30 km/s) and impacted onto various target surfaces. These surfaces vary in their density (Ag and Au) as well as in their morphology by including highly porous nanostructured surfaces (“metal blacks”) in the study. After impact, the polymer chains of the latex particles are chemically degraded to much smaller molecular fragments. These fragments include both carbon- and sulphur-based species, which are detected as positive and negative ions by time-of-flight mass spectrometry. The mass spectra show that greater degradation occurs at higher velocities until finally only very simple molecular or atomic ions are formed. An effort is made to rationalise this strong velocity dependence based on energetic arguments. Furthermore, black surfaces lead to higher fragmentation than compact surfaces, which could be a consequence of much smaller impact spots. These results suggest organic molecule formation during expansion from the high pressure shock state.
Published: 2011

16. George F. Kennan und die Kurskorrektur der amerikanischen Außenpolitik nach dem Zweiten Weltkrieg

Author: Klaus Hornung
Published: 2011

17. Control of Nano-Scale Structuring and Reinforcement in Rotational Molding of Polyethylene

Author: Manfred H. Wagner, Oleg Kulikov, and Klaus Hornung
Subjects: chemistry.chemical_classification, Materials science, Polymers and Plastics, Silica fume, Organic Chemistry, technology, industry, and agriculture, Sintering, Polymer, Polyethylene, Condensed Matter Physics, Pelletizing, Rotational molding, chemistry.chemical_compound, chemistry, Thermal, Materials Chemistry, Extrusion, Composite material
Abstract: Polyethylene (PE) resins used for Rotational Molding have usually particle sizes less than 0.8 mm and used as powders or micro-pellets. During heating in a rotating mould, these particles get fused and merge into one piece. A disadvantage of the rotomolding process is long cycle times that affect the production rate and increase thermal degradation of the polymer. One of the problems in rotomolding is bubbles of gasses trapped during sintering of the PE powders which reduce mechanical strength of the article produced. We propose to use reacting mixtures of PEG with citric acid as Processing Additive (PA) to rotomolding grades of PE. Silica fume and vinyl-silanes can be other ingredients of the additive package. The PA accelerates sintering of the PE particulates and greatly reduces number of bubbles in the melt but at high concentrations it impedes flow of the particles. Powders are characterized by low flowability while micro-pellets have too high flowability for rotomolding. To improve the rotomolding process we propose to fabricate micro-pellets by extrusion of PE resins comprising the PA at reduced temperatures and pelletizing in open air. The same PA reduces extrusion pressure and suppresses flow instabilities during pelletizing as well as adjusts flowability of micro-pellets to optimum, accelerates sintering of the PE particulates and removes bubbles from the PE melt. Mechanisms of the observed improvements are discussed.
Published: 2010

18. Low viscous hydrophilic processing additives for extrusion of polyethylene at reduced temperatures

Author: Manfred H. Wagner, Klaus Hornung, and Oleg Kulikov
Subjects: Materials science, Polymers and Plastics, Production cost, Sharkskin, General Chemistry, Polyethylene glycol, Polyethylene, Apparent viscosity, Polyester, chemistry.chemical_compound, chemistry, Materials Chemistry, Extrusion, Composite material, Phosphoric acid
Abstract: Industry is using fluorinated polymer processing additives (PPA) to delay the onset of sharkskin to higher rates of extrusion of PE resins. Yet it is necessary to keep elevated temperatures during extrusion to reduce apparent melt viscosity. We propose to use low viscous PPA made from reacting mixtures of polyethylene glycol with organic polyacids, phosphoric acid, and polyesters of oxiacids of Phosphorus. Surprisingly, extrusion pressures and apparent viscosity with the novel PPA at reduced temperatures are less, than at elevated temperatures. In total, extrusion pressures can be reduced 2–5 times for concentrations of PPA from 0.1 to 0.5 wt%, while sharkskin melt fracture can be eliminated for concentrations of PPA above 0.02 wt%. Extrusion with the novel PPA at reduced temperatures potentially increases productivity, reduces production cost, and allows processing of PE resins ofhigher MW and highly filled polymer composites. POLYM. ENG. SCI., 2010. © 2010 Society of Plastics Engineers
Published: 2010

19. Silanols cured by borates as lubricants in extrusion of LLDPE. Impact of elasticity of the lubricant on sliding friction

Author: Manfred H. Wagner, Oleg Kulikov, and Klaus Hornung
Subjects: Materials science, Sharkskin, Polyethylene, Tribology, Condensed Matter Physics, Linear low-density polyethylene, chemistry.chemical_compound, chemistry, Lubrication, General Materials Science, Extrusion, Lubricant, Elasticity (economics), Composite material
Abstract: Addition of a viscoelastic material based on silanols cured by boron oxide was used to delay sharkskin and stick–slip instabilities in extrusion of linear low-density polyethylene (LLDPE). Delay of flow instabilities to rates of extrusion 25–35 times higher than without additive and about 40% less extrusion pressure at the same throughput are achieved by the use of this material as an additive (∼0.1%) to LLDPE or as a coating of the extrusion die. Mechanical properties of the lubricant were changed by small variations of composition to investigate the impact of elasticity on lubrication and sharkskin delay. Both lubrication and sharkskin delay were considerably improved when more elastic lubricants were used while the chemical composition of the lubricants was nearly the same. Filling the lubricants with powders of metal oxides or especially particulates having plate-like particles (kaolin, mica, BN) helped to delay the flow instabilities further to even higher throughputs. Together with experimental results, we present a tentative explanation for the importance of elasticity of polymer processing aids in the delay of sharkskin and the stabilization of slip.
Published: 2007

20. COSIMA-Rosetta calibration for in-situ characterization of 67P/Churyumov-Gerasimenko cometary inorganic compounds

Author: Martin Hilchenbach, Thomas Stephan, Christelle Briois, Nicolas Fray, Donia Baklouti, Jouni Rynö, François-Régis Orthous-Daunay, Harry Lehto, Laurent Thirkell, Klaus Hornung, Harald Krüger, Mario Trieloff, Johan Silen, Rita Schulz, Henning Fischer, Sihane Merouane, Cécile Engrand, Sandra Siljeström, Max Planck Institute for Solar System Research (MPS), Max-Planck-Gesellschaft, Department of Geophysical Sciences [Chicago], University of Chicago, Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM AS), Université Paris-Saclay-Univ. Paris-Sud-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), 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), Department of Chemistry, Materials and Surfaces [Boras], SP Technical Research Institute of Sweden, Max-Planck-Institut für Sonnensystemforschung (MPS), Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institute for Meteorology and Climate Research (IMK), Karlsruhe Institute of Technology (KIT), Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA (UMR_7583)), Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut für Strömungsmechanik und Aerodynamik (LRT-7), Universität der Bundeswehr München [Neubiberg], Tuorla Observatory, University of Turku, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG ), Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Finnish Meteorological Institute Observation Services, Finnish Meteorological Institute (FMI), European Space Research and Technology Centre (ESTEC), European Space Agency (ESA), Institut für Geowissenschaften [Heidelberg], Universität Heidelberg [Heidelberg], Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Saclay-Univ. Paris-Sud, Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Centre National d’Études Spatiales [Paris] (CNES), Institut für Meteorologie und Klimaforschung (IMK), Karlsruher Institut für Technologie (KIT), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), and Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Institut national des sciences de l'Univers (INSU - CNRS)
Subjects: Earth and Planetary Astrophysics (astro-ph.EP), Materials science, Mineral, ta115, Comet, FOS: Physical sciences, Astronomy and Astrophysics, 010502 geochemistry & geophysics, 01 natural sciences, Astrobiology, Secondary ion mass spectrometry, Interplanetary dust cloud, Meteorite, 13. Climate action, Space and Planetary Science, Micrometeorite, [SDU]Sciences of the Universe [physics], 0103 physical sciences, Mass spectrum, 010303 astronomy & astrophysics, Refractory (planetary science), 0105 earth and related environmental sciences, Astrophysics - Earth and Planetary Astrophysics
Abstract: COSIMA (COmetary Secondary Ion Mass Analyser) is a time-of-flight secondary ion mass spectrometer (TOF-SIMS) on board the Rosetta space mission. COSIMA has been designed to measure the composition of cometary dust grains. It has a mass resolution m/{\Delta}m of 1400 at mass 100 u, thus enabling the discrimination of inorganic mass peaks from organic ones in the mass spectra. We have evaluated the identification capabilities of the reference model of COSIMA for inorganic compounds using a suite of terrestrial minerals that are relevant for cometary science. Ground calibration demonstrated that the performances of the flight model were similar to that of the reference model. The list of minerals used in this study was chosen based on the mineralogy of meteorites, interplanetary dust particles and Stardust samples. It contains anhydrous and hydrous ferromagnesian silicates, refractory silicates and oxides (present in meteoritic Ca-Al-rich inclusions), carbonates, and Fe-Ni sulfides. From the analyses of these minerals, we have calculated relative sensitivity factors for a suite of major and minor elements in order to provide a basis for element quantification for the possible identification of major mineral classes present in the cometary grains., Comment: 20 pages, 3 figures, 5 tables
Published: 2015

21. Comet 67P/Churyumov-Gerasimenko sheds dust coat accumulated over the past four years

Author: M. Godard, Martin Hilchenbach, François-Régis Orthous-Daunay, Harry Lehto, Kurt Varmuza, Donia Baklouti, Klaus Hornung, John Paquette, Jouni Rynö, Yves Langevin, Hervé Cottin, Nicolas Fray, Sihane Merouane, Oliver Stenzel, Rita Schulz, Henning Fischer, Anais Bardyn, Johan Silen, Jochen Kissel, Christelle Briois, Laurent Thirkell, Cécile Engrand, B. Zaprudin, Léna Le Roy, Sandra Siljeström, Max-Planck-Institut für Sonnensystemforschung (MPS), Max-Planck-Gesellschaft, Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-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)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Centre National d’Études Spatiales [Paris] (CNES), Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse (CSNSM), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA (UMR_7583)), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Institut national des sciences de l'Univers (INSU - CNRS), Tuorla Observatory, University of Turku, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Max Planck Institute for Solar System Research (MPS), 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), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG ), Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Sonnensystemforschung ( MPS ), Institut d'astrophysique spatiale ( IAS ), Université Paris-Sud - Paris 11 ( UP11 ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace ( LPC2E ), Centre National de la Recherche Scientifique ( CNRS ) -Université d'Orléans ( UO ) -Institut national des sciences de l'Univers ( INSU - CNRS ), Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse ( CSNSM ), Université Paris-Sud - Paris 11 ( UP11 ) -Institut National de Physique Nucléaire et de Physique des Particules du CNRS ( IN2P3 ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire Inter-universitaire des Systèmes Atmosphériques, LISA/IPSL, Université Paris Est et Paris Diderot, CNRS/INSU UMR 7583, Créteil, France, Laboratoire inter-universitaire des systèmes atmosphèriques ( LISA ), Institut national des sciences de l'Univers ( INSU - CNRS ) -Université Paris Diderot - Paris 7 ( UPD7 ) -Université Paris-Est Créteil Val-de-Marne - Paris 12 ( UPEC UP12 ) -Centre National de la Recherche Scientifique ( CNRS ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Université Paris Diderot - Paris 7 ( UPD7 ) -Université Paris-Est Créteil Val-de-Marne - Paris 12 ( UPEC UP12 ) -Centre National de la Recherche Scientifique ( CNRS ), Institut national des sciences de l'Univers ( INSU - CNRS ) -Université Paris Diderot - Paris 7 ( UPD7 ) -Université Paris-Est Créteil Val-de-Marne - Paris 12 ( UPEC UP12 ) -Centre National de la Recherche Scientifique ( CNRS ), Institut de Planétologie et d'Astrophysique de Grenoble ( IPAG ), Observatoire des Sciences de l'Univers de Grenoble ( OSUG ), Université Joseph Fourier - Grenoble 1 ( UJF ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Grenoble Alpes ( UGA ) -Université Joseph Fourier - Grenoble 1 ( UJF ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Grenoble Alpes ( UGA ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire Magmas et Volcans ( LMV ), Université Blaise Pascal - Clermont-Ferrand 2 ( UBP ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Université Jean Monnet [Saint-Étienne] ( UJM ) -Centre National de la Recherche Scientifique ( CNRS ), and Max Planck Institute for Solar System Research ( MPS )
Subjects: ta115, Multidisciplinary, Comet dust, Astronomical unit, Comet, ta1171, Mantle (geology), Asteroids, Astrobiology, Interplanetary dust cloud, 13. Climate action, [SDU]Sciences of the Universe [physics], Comet nucleus, Formation and evolution of the Solar System, comets and Kuiper belt, [ SDU ] Sciences of the Universe [physics], Geology, Cosmic dust
Abstract: International audience; Comets are composed of dust and frozen gases. The ices are mixed with the refractory material either as an icy conglomerate1, or as an aggregate of pre-solar grains (grains that existed prior to the formation of the Solar System), mantled by an ice layer2, 3. The presence of water-ice grains in periodic comets is now well established4, 5, 6. Modelling of infrared spectra obtained about ten kilometres from the nucleus of comet Hartley 2 suggests that larger dust particles are being physically decoupled from fine-grained water-ice particles that may be aggregates7, which supports the icy-conglomerate model. It is known that comets build up crusts of dust that are subsequently shed as they approach perihelion8, 9, 10. Micrometre-sized interplanetary dust particles collected in the Earth’s stratosphere and certain micrometeorites are assumed to be of cometary origin11, 12, 13. Here we report that grains collected from the Jupiter-family comet 67P/Churyumov-Gerasimenko come from a dusty crust that quenches the material outflow activity at the comet surface14. The larger grains (exceeding 50 micrometres across) are fluffy (with porosity over 50 per cent), and many shattered when collected on the target plate, suggesting that they are agglomerates of entities in the size range of interplanetary dust particles. Their surfaces are generally rich in sodium, which explains the high sodium abundance in cometary meteoroids15. The particles collected to date therefore probably represent parent material of interplanetary dust particles. This argues against comet dust being composed of a silicate core mantled by organic refractory material and then by a mixture of water-dominated ices2, 3. At its previous recurrence (orbital period 6.5 years), the comet’s dust production doubled when it was between 2.7 and 2.5 astronomical units from the Sun14, indicating that this was when the nucleus shed its mantle. Once the mantle is shed, unprocessed material starts to supply the developing coma, radically changing its dust component, which then also contains icy grains, as detected during encounters with other comets closer to the Sun4, 5.
Published: 2015

22. Ion formation by high velocity impacts on porous metal targets

Author: Jochen Kissel, Klaus Hornung, and Eva Maria Mellado
Subjects: Materials science, Mechanical Engineering, Aerospace Engineering, Ocean Engineering, Mass spectrometry, Molecular physics, Grain size, Ion, Impact ionization, Mechanics of Materials, Ionization, Automotive Engineering, Particle, Safety, Risk, Reliability and Quality, Porosity, Civil and Structural Engineering, Cosmic dust
Abstract: In impact ionization studies the target normally consists of a metal surface of compact solid density. In the present experiments, we investigate the use of a layer of a highly porous structure of nanometre-sized grains, sometimes also called "metal black", as an alternative target. In our comparative experiments, spherical iron particles (0.1
Published: 2006

23. Novel processing aid based on modified Silly Putty®

Author: Oleg Kulikov and Klaus Hornung
Subjects: Marketing, Materials science, Polymers and Plastics, Borax, General Chemical Engineering, Plastics extrusion, Sharkskin, General Chemistry, engineering.material, Polyethylene, Linear low-density polyethylene, Boric acid, chemistry.chemical_compound, Coating, chemistry, Polymer chemistry, Materials Chemistry, engineering, Extrusion, Composite material
Abstract: A viscoelastic material based on low-molecular-weight silanols cured by boric acid, i.e., having a composition similar to that of the well-known Silly Putty®, was used to delay sharkskin and stick–slip instabilities in the extrusion of linear low-density polyethylene (LLDPE). The use of sodium hydroxide and phosphoric acid in the composition helped to improve adhesion of the material to metal and to extend its efficiency above 200°C. Adding powders of metal oxides, e.g., borax, silica, and especially silicates, further helped to delay the flow instabilities. A delay of the sharkskin instability to 25–35 times higher extrusion rates was achieved, and about 45% less pressure was observed in a screw extruder at the same throughput when this material was used as an additive to LLDPE (∼0.1%) or as a coating of the extrusion die. Tentative explanations of the sharkskin origin and for the delay of the instability are proposed. J. VINYL. ADDIT. TECHNOL., 12:131–142, 2006. © 2006 Society of Plastics Engineers
Published: 2006

24. Collecting Cometary Dust Particles on Metal Blacks with The COSIMA Instrument Onboard ROSETTA

Author: Martin Hilchenbach, Massimiliano Rossi, Henning Fischer, Harald Krüger, Jochen Kissel, Cécile Engrand, Oleg Kulikov, Klaus Hornung, Yves Langevin, Eva Maria Mellado, Franz R. Krueger, CSNSM AS, Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse (CSNSM), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), and Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Sud - Paris 11 (UP11)
Subjects: High probability, Physics, MICROMETEORITES, [PHYS]Physics [physics], Cometary dust, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Dust particles, Comet, Metal blacks, [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Astronomy, ANTARCTIC SNOW, Astronomy and Astrophysics, Internal friction, EVOLUTION, Astrobiology, Space and Planetary Science, Rosetta mission, Collection efficiency
Abstract: International audience; After a brief review of the instrument development and materials selection for collecting cometary dust in the vicinity of comet 67/P Churyumov-Gerasimenko we focus on laboratory verification for the capability of metal black targets to decelerate and capture dust particles (velocities in the order of 100 m/s; sizes of some 10 mu m). The results indicate that particles between 10 and 100 mu m size can be collected with high probability. Two basic mechanisms of energy dissipation upon impact could be identified: By internal friction within a highly structured dust and within the black's nanostructure. In addition to the actual ROSETTA mission the data presented here might have a more general relevance for future, similar in-situ investigations. (C) 2014 Elsevier Ltd. All rights reserved.
Published: 2014

25. Mechanisms of shark skin suppression by novel polymer processing aids

Author: Manfred H. Wagner, Klaus Hornung, Oleg Kulikov, and T. Himmel
Subjects: chemistry.chemical_compound, Materials science, chemistry, Rheometry, Shear stress, Newtonian fluid, Sharkskin, Extrusion, Slip (materials science), Thermoplastic elastomer, Composite material, Polyethylene
Abstract: The extrusion rate of polyethylene (PE) with narrow molar weight distribution, as e.g. metallocen catalysed polyethylene (m-PE), is limited by melt fracture. The first level of fracture is a surface defect called sharkskin. Common polymer processing aids based on fluorinated polymers shift the onset of sharkskin to higher extrusion rates by creating a "low energy surface" at the die wall and promoting wall slip. Alternatively, Kulikov et al. [1, 2] suggested thermoplastic elastomers (TPE) for sharkskin suppression, and Muller [3] showed the suitability of some TPEs as polymer processing aids. We investigated the slip velocity of several TPEs against steel, and the slip velocity in a polymeric interface between polyethylene (PE) and TPE by rotational plate-plate rheometry in the Newtonian flow regime. TPEs with lower viscosities showed higher slip velocities against steel. However, the interfacial slip velocities between PE and TPE were found to be viscosity independent. In both cases, the slip velocity was found to be proportional to the applied shear stress.
Published: 2014

26. [Untitled]

Author: Yuri G. Malama, Khaim S. Kestenboim, and Klaus Hornung
Subjects: Physics, Astronomy and Astrophysics, Astrobiology, Computational physics, Atmosphere, Interplanetary dust cloud, Space and Planetary Science, Ionization, Vaporization, Hypervelocity, Particle, Astrophysics::Earth and Planetary Astrophysics, Interplanetary spaceflight, Astrophysics::Galaxy Astrophysics, Cosmic dust
Abstract: We report on theoretical efforts to understand the process of vaporization and ion formation upon hypervelocity impact of small cosmic dust particles on a solid surface. Such collisions occur at the surface of solid bodies within the planetary system, which do not have an atmosphere as well as in various actual and upcoming space missions for in-situ measurements of interplanetary, interstellar and cometary dust. The investigation uses Godunov's method to simulate the impact. For the very high velocitites investigated, the impacting dust particle as well as parts of the target vaporize and some of the vapor cloud may change to partially ionized. Numerical results of the impact process are communicated for an 80 kms-1impact of a slightly porous SiO2 particle on a compact SiO2surface. Values of the amount of vapor and liquid excavated from the target are given. Ionization rates are calculated for the example investigated and an estimate is given how this extrapolates to the highest conceivable velocities in the planetary system (above 100 km s-1).
Published: 2000

27. A linear tof mass spectrometer as a tool for the investigation of impact ionisation plasma

Author: Theresa Johnson, Zoltan Sternovsky, Eberhard Grün, Anna Mocker, Sascha Kempf, Ralf Srama, and Klaus Hornung
Subjects: Chemistry, Ionization, Dust particles, Hypervelocity, Energy density, Particle, Plasma, Atomic physics, Mass spectrometry, Astrophysics::Galaxy Astrophysics, Ion
Abstract: The generation of charge during hypervelocity impacts of microparticles provides one of the most sensitive methods for the detection and characterisation of dust particles in space. Linear time-of- flight (TOF) mass spectrometry provides an opportunity for investigating the thermodynamical properties of an impact ionisation plasma, e.g. the velocity distribution of the ions. The dependence of the plasma properties on the impact parameters were studied at the Heidelberg dust accelerator laboratory using impacts speed from 1 to 90 kms-1 and particle sizes form 30nm to 4μm. The results imply that the defining parameter of impact ionisation is either the impact velocity or the energy density and not the total impact energy.
Published: 2012

28. A Study to Compare Oral Sumatriptan with Oral Aspirin plus Oral Metoclopramide in the Acute Treatment of Migraine

Author: Kenji Tako, Carlo Doriguzzi, Umberto Balottin, F. Carboni, F. Zoroddu, Tiziana Mongini, J. J. M. Askenasy, Naoyuki Tsukada, Kinichi Hisada, Emanuela Maserati, Juan Sanchez-Ramos, S. Manca, Camillo Mastropaolo, Cristiana Caramella, C. Patrini, Reinhold Schmidt, Luigi Manfredi, Pierangelo Veggiotti, P A Uldry, F. Pasquali, Wilfred A. Nix, D. Franciotta, Nariyoshi Yamaguchi, L. Bet, Carola Ponzetto, M. Poloni, Nobuo Yanagisawa, Julien Bogousslavsky, Ryoichi Hayashi, Laura Palmucci, Hiroshi Morita, A. Ottolini, Paolo Mazzarello, Nereo Bresolin, Carlos Singer, William J. Weiner, Klaus Hornung, M. Tondi, A. De Francesco, Itsuki Jibiki, Hiroshi Matsuda, Umberto Laforenza, and Giovanni Lanzi
Subjects: medicine.medical_specialty, Oral treatment, Aspirin, Metoclopramide, Acute migraine, business.industry, medicine.disease, Gastroenterology, stomatognathic diseases, Sumatriptan, Dispersible tablet, Neurology, Migraine, Tolerability, Internal medicine, medicine, Neurology (clinical), business, medicine.drug
Abstract: In a double-blind, placebo-controlled study, the efficacy, safety and tolerability of 100 mg oral sumatriptan, given as a dispersible tablet, was compared with that of 900 mg oral aspirin plus 10 mg o
Published: 1992

29. Novel processing additives for extrusion and injection of polymers

Author: Manfred H. Wagner, Oleg Kulikov, and Klaus Hornung
Subjects: chemistry.chemical_classification, Materials science, Sharkskin, Polymer, Polyethylene glycol, Viscoelasticity, chemistry.chemical_compound, chemistry, Chemical engineering, Fluorinated Polymers, Molar mass distribution, Organic chemistry, Extrusion, Thickening agent
Abstract: This chapter presents experimental results and tentative explanations for the origin of sharkskin and of slip in extrusion of polyolefins with narrow molecular weight distribution as well as plausible mechanisms of sharkskin suppression by the use of viscoelastic polymer processing additives (PPA). Various types of conventional PPAs are reviewed briefly and then novel PPAs are proposed. The novel PPAs are composed of polyethylene glycol (PEG) with molecular weights from 1000 to 10 000 Da, esters of oxoacids of boron or phosphorus and optionally a thickening agent. In contrast to conventional PPAs made from fluorinated polymers and siloxanes, the novel PPAs are hydrophilic and they can be made from cheap and FDA-compliant components.
Published: 2009

30. Impact of Elasticity on Lubrication. Esters of PEG, Silanol and their Blends as Polymer Processing Additives

Author: Oleg L. Kulikov, Klaus Hornung, Manfred H. Wagner, Albert Co, Gary L. Leal, Ralph H. Colby, and A. Jeffrey Giacomin
Subjects: chemistry.chemical_classification, Silanol, chemistry.chemical_compound, Materials science, chemistry, PEG ratio, Molar mass distribution, Organic chemistry, Sharkskin, Extrusion, Polymer, Polyethylene glycol, Thickening agent
Abstract: We present experimental results and tentative explanations for the origin of sharkskin in extrusion of polyolefins with narrow molecular weight distribution as well as plausible mechanisms of sharkskin suppression by the use of viscoelastic Polymer Processing Additives (PPA). Novel PPAs are proposed. The novel PPAs are composed of esters of oxoacids of Boron and Phosphorus and Polyethylene Glycol (PEG) with molecular weights from 1000 to 10,000 Da, and optionally contain silanols and a thickening agent. In contrast to conventional PPAs made from fluorinated polymers and siloxanes, the novel PPAs are hydrophilic and they can be made from cheap and FDA‐compliant components.
Published: 2008

31. Cosima High Resolution Time-of-Flight Secondary Ion Mass Spectrometer for the Analysis of Cometary Dust Particles onboard Rosetta

Author: H. Höfner, R. Thomas, Kathrin Altwegg, Rita Schulz, Albrecht Glasmachers, Erich R. Schmid, Klaus Hornung, Eberhard Grün, H. von Hoerner, Yves Langevin, H. Zscheeg, F. Rüdenauer, Hervé Cottin, Gerhard Haerendel, J. Eibl, N. G. Utterback, Berndt Feuerbacher, Jouni Rynö, W. Steiger, J. M. Greenberg, S. Czempiel, K. M. Torkar, Cecile Engrand, Thomas Stephan, B. C. Clark, H. Henkel, M. Fomenkova, H. M. Fehringer, François Raulin, P. Parigger, Wolfgang Werther, Johan Silen, Kurt Varmuza, Luigi Colangeli, Martin Hilchenbach, K.-P. Wanczek, Andreas Koch, Laurent Thirkell, Harald Krüger, Jochen Kissel, and Elmar K. Jessberger
Subjects: Secondary ion mass spectrometry, Time of flight, Solar System, Ion beam, Space and Planetary Science, Comet, Mass spectrum, Astronomy and Astrophysics, Astrophysics, Atomic physics, Mass spectrometry, Ion
Abstract: The ESA mission Rosetta, launched on March 2nd, 2004, carries an instrument suite to the comet 67P/Churyumov-Gerasimenko. The COmetary Secondary Ion Mass Anaylzer – COSIMA – is one of three cometary dust analyzing instruments onboard Rosetta. COSIMA is based on the analytic measurement method of secondary ion mass spectrometry (SIMS). The experiment’s goal is in-situ analysis of the elemental composition (and isotopic composition of key elements) of cometary grains. The chemical characterization will include the main organic components, present homologous and functional groups, as well as the mineralogical and petrographical classification of the inorganic phases. All this analysis is closely related to the chemistry and history of the early solar system. COSIMA covers a mass range from 1 to 3500 amu with a mass resolution m/Δm @ 50% of 2000 at mass 100 amu. Cometary dust is collected on special, metal covered, targets, which are handled by a target manipulation unit. Once exposed to the cometary dust environment, the collected dust grains are located on the target by a microscopic camera. A pulsed primary indium ion beam (among other entities) releases secondary ions from the dust grains. These ions, either positive or negative, are selected and accelerated by electrical fields and travel a well-defined distance through a drift tube and an ion reflector. A microsphere plate with dedicated amplifier is used to detect the ions. The arrival times of the ions are digitized, and the mass spectra of the secondary ions are calculated from these time-of-flight spectra. Through the instrument commissioning, COSIMA took the very first SIMS spectra of the targets in space. COSIMA will be the first instrument applying the SIMS technique in-situ to cometary grain analysis as Rosetta approaches the comet 67P/Churyumov-Gerasimenko, after a long journey of 10 years, in 2014.
Published: 2007

32. Cometary and Interstellar Dust Analyzer for comet Wild 2

Author: Michael E. Zolensky, H. Höfner, J. M. Greenberg, H. von Hoerner, B. C. Clark, Martha S. Hanner, Friedrich Hoerz, H. Henkel, Johan Silen, Jochen Kissel, D. Möhlmann, Z. Sekanina, Scott A. Sandford, Elmar K. Jessberger, A. Glasmachers, Eberhard Grün, Peter Tsou, Klaus Hornung, Gerhard Haerendel, N. G. Utterback, C. Heiss, Donald E. Brownlee, Yves Langevin, and F. R. Krueger
Subjects: Atmospheric Science, Comet dust, Comet, Soil Science, Coma (optics), Astrophysics, Aquatic Science, Oceanography, Astrobiology, Geochemistry and Petrology, Comet nucleus, Interplanetary dust, Earth and Planetary Sciences (miscellaneous), Earth-Surface Processes, Water Science and Technology, Cosmic dust, Physics, Ecology, Comet tail, Halley's Comet, Paleontology, Instruments and techniques, Forestry, Atomic mass unit, Interplanetary Physics, Geophysics, Space and Planetary Science
Abstract: [1] The Cometary and Interstellar Dust Analyzer (CIDA) instrument analyzes the composition of individual grains in the cometary coma. As each particle impacts a silver plate, the high-impact energy due to the relative velocity of the spacecraft as it flies through the coma causes the elements and molecular compounds in the particle to become ionized. Using a fast time-of-flight mass spectrometer, a complete set of ions are detected for each impact, from a mass range of 1 (atomic hydrogen) up to a few thousand atomic mass units, encompassing all elements in the periodic table and many molecules, such as organic compounds. This experimental technique has already been applied with excellent success at Halley's comet, and the CIDA derivative instrument is flying on the Stardust mission, which will encounter comet Wild 2 in January of 2004. The data returned will give clues to the elemental and chemical composition of the dust component of this comet.
Published: 2003

33. On the applicability of laser ionization for simulating hypervelocity impacts

Author: Sascha Kempf, Eberhard Grün, Klaus Hornung, Zoltan Sternovsky, Ralf Srama, K. Drake, and Anna Mocker
Subjects: Physics, Spacecraft, business.industry, Instrumentation, General Physics and Astronomy, Laser, Computational physics, law.invention, Impact ionization, law, Ionization, Hypervelocity, Particle, Physics::Atomic Physics, Atomic physics, business, Cosmic dust
Abstract: In-situ measurements, the direct interception and analysis of dust particles by spacecraft-based instrumentation, provide insights into the dynamical, physical and chemical properties of cosmic dust. The most sensitive detection methods for dust particles in space are based on impact ionization. Laser ionization is used for the test, development, and calibration of impact ionization instruments and to complement laboratory based particle impact experiments. A typical setup uses a 355 nm Nd-YAG laser with a pulse length of about 5 ns. It is necessary to investigate the properties of both processes with respect to their comparability. A study was performed to find out to what extent laser ionization can be used to simulate impact ionization. The findings show that laser ionization and impact ionization show similarities, which can be used to test the functionality of dust impact detectors, especially time-of-flight instruments. Our paper provides information on what extent these similarities hold and where ...
Published: 2012

34. EEG changes in patients during the introduction of carbamazepine

Author: Roland Besser, Günter Krämer, Gerhard Rothacher, M. Theisohn, and Klaus Hornung
Subjects: Adult, Male, Pretreatment Period, Adolescent, Observation period, Relative power, Electroencephalography, medicine, Humans, In patient, Aged, Individual susceptibility, Epilepsy, medicine.diagnostic_test, General Neuroscience, Signal Processing, Computer-Assisted, Carbamazepine, Middle Aged, Alpha band, Anesthesia, Female, Neurology (clinical), Psychology, medicine.drug
Abstract: This study evaluates the EEG changes during the standardized introduction of carbamazepine in 16 previously untreated neurological patients and their relationship to serum levels of carbamazepine and carbamazepine-10,11-epoxide. Therapy was started with a dosage of 400 mg carbamazepine b.i.d. and remained unchanged during the whole study period of 35 days. Frequency analysis of serial EEG records was performed by Fast Fourier Transformation. In comparison to the pretreatment period (1) the mean values of the total power and relative powers of the theta and delta bands increased and (2) the mean values of the relative power of the alpha band and the center frequency decreased. These changes were already established 3 days after the beginning of the treatment and remained constant during the observation period. There were marked interindividual differences. (3) There was no statistically significant correlation between serum levels of carbamazepine or carbamazepine-10,11-epoxide and the EEG parameters. Our results demonstrate that the degree of EEG change primarily reflects individual susceptibility to carbamazepine and its metabolite during the early stage of carbamazepine exposure and is not dose related.
Published: 1992

35. Silanols cured by borates as lubricants in extrusion of LLDPE. Impact of elasticity of the lubricant on sliding friction.

Author: Oleg Kulikov, Klaus Hornung, and Manfred Wagner
Subjects: *BORATES, *SYNTHETIC lubricants, *ELASTICITY, *PLASTIC extrusion
Abstract: AbstractÂ Â Addition of a viscoelastic material based on silanols cured by boron oxide was used to delay sharkskin and stickâslip instabilities in extrusion of linear low-density polyethylene (LLDPE). Delay of flow instabilities to rates of extrusion 25â35 times higher than without additive and about 40% less extrusion pressure at the same throughput are achieved by the use of this material as an additive (â¼0.1%) to LLDPE or as a coating of the extrusion die. Mechanical properties of the lubricant were changed by small variations of composition to investigate the impact of elasticity on lubrication and sharkskin delay. Both lubrication and sharkskin delay were considerably improved when more elastic lubricants were used while the chemical composition of the lubricants was nearly the same. Filling the lubricants with powders of metal oxides or especially particulates having plate-like particles (kaolin, mica, BN) helped to delay the flow instabilities further to even higher throughputs. Together with experimental results, we present a tentative explanation for the importance of elasticity of polymer processing aids in the delay of sharkskin and the stabilization of slip. [ABSTRACT FROM AUTHOR]
Published: 2007
Full Text: View/download PDF

36. Sozialismus und Kommunismus in Griechenland

Author: Klaus Hornung
Abstract: Im Falle Griechenlands wird die Erkenntnis der vergleichenden Regierungslehre in besonderer Weise bestatigt, das Struktur und Funktion, Ideologie und Programmatik der politischen Parteien nur im Rahmen des gesamten politischen Systems und der politischen Kultur, denen sie zugehoren, zureichend untersucht und verstanden werden konnen. Bei allen engen Verbindungen Griechenlands zu Westeuropa seit den Tagen der Franzosischen Revolution und des griechischen Unabhangigkeitskampfes, die sich nicht zuletzt in der neugriechischen Verfassungsgeschichte widerspiegeln, und bei allem betont westeuropaischen Selbstverstandnis der griechischen Fuhrungsschicht, kann man die sozio-kulturellen Strukturbesonderheiten dieses Landes nicht ubersehen, ohne deren Kenntnis auch die heutigen tiefgreifenden gesellschaftlichen, kulturellen und politischen Wandlungen in Griechenland unverstandlich bleiben mussen.1
Published: 1978

Catalog

Books, media, physical & digital resources

See catalog results

Searchworks

Select search scope, currently: Articles Catalog books, media & more in Jio Institute collections Articles journal articles & other e-resources

Search

Search Constraints

Refine your results

Search Limiters

Topic

Publication Year Range

Language

Publication Type

Journal

Database

Publisher

36 results on '"Klaus Hornung"'

Search Results

Catalog

Select search scope, currently: Articles

Catalog

books, media & more in Jio Institute collections

Articles

journal articles & other e-resources