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In: Bulletin of the atomic scientists, Volume 17, Issue 5-6, p. 194-199
ISSN: 1938-3282
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In: Bulletin of the atomic scientists, Volume 17, Issue 5-6, p. 194-199
ISSN: 1938-3282
In: The bulletin of the atomic scientists: a magazine of science and public affairs, Volume 17, p. 194-199
ISSN: 0096-3402, 0096-5243, 0742-3829
The European Space Agency's Planck satellite, dedicated to studying the early Universe and its subsequent evolution, was launched 14 May 2009 and has been scanning the microwave and submillimetre sky continuously since 12 August 2009. In March 2013, ESA and the Planck Collaboration released the initial cosmology products based on the first 15.5 months of Planck data, along with a set of scientific and technical papers and a web-based explanatory supplement. This paper gives an overview of the mission and its performance, the processing, analysis, and characteristics of the data, the scientific results, and the science data products and papers in the release. The science products include maps of the cosmic microwave background (CMB) and diffuse extragalactic foregrounds, a catalogue of compact Galactic and extragalactic sources, and a list of sources detected through the Sunyaev-Zeldovich effect. The likelihood code used to assess cosmological models against the Planck data and a lensing likelihood are described. Scientific results include robust support for the standard six-parameter ΛCDM model of cosmology and improved measurements of its parameters, including a highly significant deviation from scale invariance of the primordial power spectrum. The Planck values for these parameters and others derived from them are significantly different from those previously determined. Several large-scale anomalies in the temperature distribution of the CMB, first detected by WMAP, are confirmed with higher confidence. Planck sets new limits on the number and mass of neutrinos, and has measured gravitational lensing of CMB anisotropies at greater than 25σ. Planck finds no evidence for non-Gaussianity in the CMB. Planck's results agree well with results from the measurements of baryon acoustic oscillations. Planck finds a lower Hubble constant than found in some more local measures. Some tension is also present between the amplitude of matter fluctuations (σ8) derived from CMB data and that derived from Sunyaev-Zeldovich data. The Planck and WMAP power spectra are offset from each other by an average level of about 2% around the first acoustic peak. Analysis of Planck polarization data is not yet mature, therefore polarization results are not released, although the robust detection of E-mode polarization around CMB hot and cold spots is shown graphically. ; Centre National D'etudes Spatiales ; CNRS/INSU-IN2P3 ; Italian Space Agency (ASI) ; Danish Natural Science Research Council ; European Space Agency ; Centre National D'etudes Spatiales ; CNRS/INSU-IN2P3-INP (France) ; Italian Space Agency (ASI) ; Italian National Research Council ; Istituto Nazionale Astrofisica (INAF) ; National Aeronautics & Space Administration (NASA) ; United States Department of Energy (DOE) ; Science & Technology Facilities Council (STFC) ; UKSA (UK) ; Consejo Superior de Investigaciones Cientificas (CSIC) ; Spanish Government ; JA (Spain) ; Finnish Funding Agency for Technology & Innovation (TEKES) ; AoF (Finland) ; CSC (Finland) ; Helmholtz Association ; German Aerospace Centre (DLR) ; Max Planck Society ; CSA (Canada) ; DTU Space (Denmark) ; SER/SSO (Switzerland) ; RCN (Norway) ; Science Foundation Ireland ; Portuguese Foundation for Science and Technology ; European Union (EU) ; Science & Technology Facilities Council (STFC) ST/I002006/1 ST/J000388/1 ST/H001239/1 ST/K000977/1 ST/K002805/1 ST/J001368/1 ST/K00333X/1 ST/I005129/1 ST/J005673/1 ST/K003674/1 ST/L000768/1 ST/G003874/1 ST/H008586/1 ST/L001314/1 ST/K004131/1 ST/M007685/1 ST/K000985/1 ST/K001051/1 ST/K00106X/1 ST/I005765/1 ST/K002899/1 ST/J004812/1
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Gaia is a cornerstone mission in the science programme of the EuropeanSpace Agency (ESA). The spacecraft construction was approved in 2006, following a study in which the original interferometric concept was changed to a direct-imaging approach. Both the spacecraft and the payload were built by European industry. The involvement of the scientific community focusses on data processing for which the international Gaia Data Processing and Analysis Consortium (DPAC) was selected in 2007. Gaia was launched on 19 December 2013 and arrived at its operating point, the second Lagrange point of the Sun-Earth-Moon system, a few weeks later. The commissioning of the spacecraft and payload was completed on 19 July 2014. The nominal five-year mission started with four weeks of special, ecliptic-pole scanning and subsequently transferred into full-sky scanning mode. We recall the scientific goals of Gaia and give a description of the as-built spacecraft that is currently (mid-2016) being operated to achieve these goals. We pay special attention to the payload module, the performance of which is closely related to the scientific performance of the mission. We provide a summary of the commissioning activities and findings, followed by a description of the routine operational mode. We summarise scientific performance estimates on the basis of in-orbit operations. Several intermediate Gaia data releases are planned and the data can be retrieved from the Gaia Archive, which is available through the Gaia home page. ; This work has made use of results from the European Space Agency (ESA) space mission Gaia, the data from which were processed by the Gaia Data Processing and Analysis Consortium (DPAC). Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement. The Gaia mission website is http: //www.cosmos.esa.int/gaia. The authors are current or past members of the ESA and Airbus DS Gaia mission teams and of the Gaia DPAC. This work has financially been supported by: the Algerian Centre de Recherche en Astronomie, Astrophysique et Géophysique of Bouzareah Observatory; the Austrian FWF Hertha Firnberg Programme through grants T359, P20046, and P23737; the BELgian federal Science Policy Office (BELSPO) through various PROgramme de Développement d'Expériences scientifiques (PRODEX) grants; the BrazilFrance exchange programmes FAPESP-COFECUB and CAPES-COFECUB; the Chinese National Science Foundation through grant NSFC 11573054; the Czech-Republic Ministry of Education, Youth, and Sports through grant LG 15010; the Danish Ministry of Science; the Estonian Ministry of Education and Research through grant IUT40-1; the European Commission's Sixth Framework Programme through the European Leadership in Space Astrometry (ELSA) Marie Curie Research Training Network (MRTN-CT-2006-033481), through Marie Curie project PIOF-GA-2009-255267 (SAS-RRL), and through a Marie Curie Transfer-of-Knowledge (ToK) fellowship (MTKD-CT-2004-014188); the European Commission's Seventh Framework Programme through grant FP7- 606740 (FP7-SPACE-2013-1) for the Gaia European Network for Improved data User Services (GENIUS) and through grant 264895 for the Gaia Research for European Astronomy Training (GREAT-ITN) network; the European Research Council (ERC) through grant 320360 and through the European Union's Horizon 2020 research and innovation programme through grant agreement 670519 (Mixing and Angular Momentum tranSport of massIvE stars – MAMSIE); the European Science Foundation (ESF), in the framework of the Gaia Research for European Astronomy Training Research Network Programme (GREATESF); the European Space Agency in the framework of the Gaia project; the European Space Agency Plan for European Cooperating States (PECS) programme through grants for Slovenia; the Czech Space Office through ESA PECS contract 98058; the Academy of Finland; the Magnus Ehrnrooth Foundation; the French Centre National de la Recherche Scientifique (CNRS) through action "Défi MASTODONS"; the French Centre National d'Etudes Spatiales (CNES); the French L'Agence Nationale de la Recherche (ANR) investissements d'avenir Initiatives D'EXcellence (IDEX) programme PSL∗ through grant ANR-10-IDEX-0001-02; the Région Aquitaine; the Université de Bordeaux; the French Utinam Institute of the Université de Franche-Comté, supported by the Région de Franche-Comté and the Institut des Sciences de l'Univers (INSU); the German Aerospace Agency (Deutsches Zentrum für Luft- und Raumfahrt e.V., DLR) through grants 50QG0501, 50QG0601, 50QG0602, 50QG0701, 50QG0901, 50QG1001, 50QG1101, 50QG140, 50QG1401, 50QG1402, and 50QG1404; the Hungarian Academy of Sciences through Lendület Programme LP2014-17; the Hungarian National Research, Development, and Innovation Office through grants NKFIH K-115709 and PD-116175; the Israel Ministry of Science and Technology through grant 3-9082; the Agenzia Spaziale Italiana (ASI) through grants I/037/08/0, I/058/10/0, 2014-025-R.0, and 2014- 025-R.1.2015 to INAF and contracts I/008/10/0 and 2013/030/I.0 to ALTEC S.p.A.; the Italian Istituto Nazionale di Astrofisica (INAF); the Netherlands Organisation for Scientific Research (NWO) through grant NWO-M-614.061.414 and through a VICI grant to A. Helmi; the Netherlands Research School for Astronomy (NOVA); the Polish National Science Centre through HARMONIA grant 2015/18/M/ST9/00544; the Portugese Fundação para a Ciência e a Tecnologia (FCT) through grants PTDC/CTE-SPA/118692/2010, PDCTE/CTEAST/81711/2003, and SFRH/BPD/74697/2010; the Strategic Programmes PEstOE/AMB/UI4006/2011 for SIM, UID/FIS/00099/2013 for CENTRA, and UID/EEA/00066/2013 for UNINOVA; the Slovenian Research Agency; the Spanish Ministry of Economy MINECO-FEDER through grants AyA2014- 55216, AyA2011-24052, ESP2013-48318-C2-R, and ESP2014-55996-C2-R and MDM-2014-0369 of ICCUB (Unidad de Excelencia María de Maeztu); the Swedish National Space Board (SNSB/Rymdstyrelsen); the Swiss State Secretariat for Education, Research, and Innovation through the ESA PRODEX programme, the Mesures d'Accompagnement, and the Activités Nationales Complémentaires; the Swiss National Science Foundation, including an Early Postdoc.Mobility fellowship; the United Kingdom Rutherford Appleton Laboratory; the United Kingdom Science and Technology Facilities Council (STFC) through grants PP/C506756/1 and ST/I00047X/1; and the United Kingdom Space Agency (UKSA) through grants ST/K000578/1 and ST/N000978/1. The GBOT programme uses observations collected at (i) the European Organisation for Astronomical Research in the Southern Hemisphere with the VLT Survey Telescope (VST), under ESO programmes 092.B-0165, 093.B-0236, 094.B-0181, 095.B-0046, 096.B-0162, and 097.B-0304; (ii) the Liverpool Telescope, which is operated on the island of La Palma by Liverpool John Moores University in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofísica de Canarias with financial support from the United Kingdom Science and Technology Facilities Council; and (iii) telescopes of the Las Cumbres Observatory Global Telescope Network. In addition to the authors of this paper, there are numerous people who have made essential contributions to Gaia, for instance those employed in the design, manufacturing, integration, and testing of the spacecraft and its modules, subsystems, and units. ; Peer-reviewed ; Publisher Version
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Seabroke, G. M., et al. ; [Context] Gaia's Early Third Data Release (EDR3) does not contain new radial velocities because these will be published in Gaia's full third data release (DR3), expected in the first half of 2022. To maximise the usefulness of EDR3, Gaia's second data release (DR2) sources (with radial velocities) are matched to EDR3 sources to allow their DR2 radial velocities to also be included in EDR3. This presents two considerations: (i) a list of 70 365 sources with potentially contaminated DR2 radial velocities has been published; and (ii) EDR3 is based on a new astrometric solution and a new source list, which means sources in DR2 may not be in EDR3. [Aims] The two aims of this work are: (i) investigate the list in order to improve the DR2 radial velocities being included in EDR3 and to avoid false-positive hypervelocity candidates; and (ii) match the DR2 sources (with radial velocities) to EDR3 sources. [Methods] Thetwo methods of this work are: (i) unpublished, preliminary DR3 radial velocities of sources on the list, and high-velocity stars not on the list, are compared with their DR2 radial velocities to identify and remove contaminated DR2 radial velocities from EDR3; and (ii) proper motions and epoch position propagation is used to attempt to match all sources with radial velocities in DR2 to EDR3 sources. The comparison of DR2 and DR3 radial velocities is used to resolve match ambiguities. [Results] EDR3 contains 7 209 831 sources with a DR2 radial velocity, which is 99.8% of sources with a radial velocity in DR2 (7 224 631). 14 800 radial velocities from DR2 are not propagated to any EDR3 sources because (i) 3871 from the list are found to either not have a DR3 radial velocity or it differs significantly from its DR2 value, and five high-velocity stars not on the list are confirmed to have contaminated radial velocities, in one case because of contamination from the non-overlapping Radial Velocity Spectrometer windows of a nearby, bright star; and (ii) 10 924 DR2 sources could not be satisfactorily matched to any EDR3 sources, so their DR2 radial velocities are also missing from EDR3. [Conclusions] The reliability of radial velocities in EDR3 has improved compared to DR2 because the update removes a small fraction of erroneous radial velocities (0.05% of DR2 radial velocities and 5.5% of the list). Lessons learnt from EDR3 (e.g. bright star contamination) will improve the radial velocities in future Gaia data releases. The main reason for radial velocities from DR2 not propagating to EDR3 is not related to DR2 radial velocity quality. It is because the DR2 astrometry is based on one component of close binary pairs, while EDR3 astrometry is based on the other component, which prevents these sources from being unambiguously matched. ; This work was supported by the Spanish Ministry of Science, Innovation and University (MICIU/FEDER, UE) through grants RTI2018-095076-B-C21, ESP2016-80079-C2-1-R, and the Institute of Cosmos Sciences University of Barcelona (ICCUB, Unidad de Excelencia 'María de Maeztu') through grants MDM-2014-0369 and CEX2019-000918-M. T.A. has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska Curie grant agreement no. 745617 and from the Ramon y Cajal Fellowship RYC2018-025968-I. The Digitized Sky Surveys were produced at the Space Telescope Science Institute under US Government grant NAG W-2166.
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In: Materials & Design, Volume 17, Issue 5-6, p. 307
In: Astropolitics: the international journal of space politics & policy, Volume 14, Issue 2-3, p. 158-176
ISSN: 1557-2943
In: Human factors: the journal of the Human Factors Society, Volume 5, Issue 3, p. 295-315
ISSN: 1547-8181
The problems to be encountered in the utilization of manned space vehicles for surveillance and reconnaissance are reviewed, together with the variables which will influence the performance of the human operator in such operations. Analyses of the theoretical capabilities of direct, unaided vision and man-periscopic vision are presented. These analyses indicate that the tasks assigned to the human operator must be examined carefully in order to ascertain that they are within his capabilities. However, the operator may be materially assisted through proper design and selection of the display-sensor system, which may overcome his inherent deficiencies. The complexity of the variables involved and the lack of much pertinent data indicates that the utilization of the human operator in any specific, system must be determined as a result of trade-offs performed during actual system development and in keeping with the specific mission objectives to be met by that system.
In: ZUMA-Arbeitsbericht, Volume 1984/05
Die Arbeit befaßt sich mit der Entwicklung eines Instruments zur Wohnquartierbeschreibung. Ziel der Wohnquartierbeschreibung soll sein, über sie auf die in diesem Wohngebiet dominante Bewohnergruppe rückzuschließen, was insbesondere bei einem Survey sinnvoll erscheint, um Personen, die wegen Nichtantreffbarkeit oder Verweigerung aus der Stichprobe herausfallen, dennoch einer sozialen Schicht bzw. Gruppe zuordnen zu können. Ausgehend von Annahmen zur sozial-räumlichen Differenzierung nach Burgess wurden neun Variablen entwickelt, die in einer standardisierten Beobachtung erhoben werden sollen (Lage, Verkehrsanbindung, Bebauungstyp, Baualter, Bebauungsdichte, Nutzungsvielfalt, Schichteinschätzung, Lebensqualität, Stadttyp). In sechs Tests wurde das Instrument angewendet und jeweils weiterentwickelt. Dabei handelte es sich um drei nationale Surveys, in die die Wohnquartiersbeschreibung eingeschaltet wurde, ferner um einen Instrumententest im Raum Mannheim, ein Zwei-Wellen-Panel in Mannheim, wobei die Wohnquartiersbeschreibung Anhang an einer Zielpersonenbefragung war, sowie um eine Untersuchung in Heidelberg zur Identifizierung schichthomogener Siedlungsstrukturen. Bei letzterem wurde auch auf die Index-Bildung eingegangen. Der Autor kommt zu dem Schluß, daß das Instrument vom Entwicklungsstand her als tauglich angesehen werden kann. Letztendlich ausschlaggebend für die Verwertung sei jedoch die Motivation und das Engagement des Beobachters. (AG)
Context. In metric theories of gravity with photon number conservation, the luminosity and angular diameter distances are related via the Etherington relation, also known as the distance duality relation (DDR). A violation of this relation would rule out the standard cosmological paradigm and point to the presence of new physics.Aims. We quantify the ability of Euclid, in combination with contemporary surveys, to improve the current constraints on deviations from the DDR in the redshift range 0< z< 1.6.Methods. We start with an analysis of the latest available data, improving previously reported constraints by a factor of 2.5. We then present a detailed analysis of simulated Euclid and external data products, using both standard parametric methods (relying on phenomenological descriptions of possible DDR violations) and a machine learning reconstruction using genetic algorithms.Results. We find that for parametric methods Euclid can (in combination with external probes) improve current constraints by approximately a factor of six, while for non-parametric methods Euclid can improve current constraints by a factor of three.Conclusions. Our results highlight the importance of surveys like Euclid in accurately testing the pillars of the current cosmological paradigm and constraining physics beyond the standard cosmological model. ; La Caixa Foundation 100010434 LCF/BQ/PI19/11690015 Spanish Agencia Estatal de Investigacion through the grant "IFT Centro de Excelencia Severo Ochoa" SEV-2016-0597 FEDER -Fundo Europeu de Desenvolvimento Regional funds through the COMPETE 2020 -Operational Programme for Competitiveness and Internationalisation (POCI) Portuguese funds through FCT -Fundacao para a Ciencia e a Tecnologia POCI-01-0145-FEDER-028987 Centro de Excelencia Severo Ochoa Program SEV-2016-059 Spanish Government RYC-2014-15843 Comision Nacional de Investigacion Cientifica y Tecnologica (CONICYT) CONICYT FONDECYT 1200171 Spanish Ministry of Science, Innovation and Universities ESP2017-89838-C3-1-R H2020 programme of the European Commission 776247 UK Research & Innovation (UKRI) Science & Technology Facilities Council (STFC) Science and Technology Development Fund (STDF) ST/P000703/1 European Research Council (ERC) 769130 Academy of Finland European Commission Agenzia Spaziale Italiana (ASI) Belgian Federal Science Policy Office Canadian Euclid Consortium Centre National D'etudes Spatiales Helmholtz Association German Aerospace Centre (DLR) Danish Space Research Institute Portuguese Foundation for Science and Technology European Commission Spanish Government National Aeronautics & Space Administration (NASA) Netherlandse Onderzoekschool Voor Astronomie Norwegian Space Agency Romanian Space Agency State Secretariat for Education, Research and Innovation (SERI) at the Swiss Space O ffice (SSO) United Kingdom Space Agency PGC2018-094773-B-C32
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In: http://hdl.handle.net/2027/osu.32435017235888
Cover title. ; "This bibliography is a continuation of the Department of the Army Pamphlet 70-5-6, published in August 1959." ; Mode of access: Internet.
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[Context] In metric theories of gravity with photon number conservation, the luminosity and angular diameter distances are related via the Etherington relation, also known as the distance duality relation (DDR). A violation of this relation would rule out the standard cosmological paradigm and point to the presence of new physics. Aims. We quantify the ability of Euclid, in combination with contemporary surveys, to improve the current constraints on deviations from the DDR in the redshift range 0 < z < 1.6. ; [Methods] We start with an analysis of the latest available data, improving previously reported constraints by a factor of 2.5. We then present a detailed analysis of simulated Euclid and external data products, using both standard parametric methods (relying on phenomenological descriptions of possible DDR violations) and a machine learning reconstruction using genetic algorithms. ; [Results] We find that for parametric methods Euclid can (in combination with external probes) improve current constraints by approximately a factor of six, while for non-parametric methods Euclid can improve current constraints by a factor of three.; [Conclusions] Our results highlight the importance of surveys like Euclid in accurately testing the pillars of the current cosmological paradigm and constraining physics beyond the standard cosmological model. ; MM has received the support of a fellowship from "la Caixa" Foundation (ID 100010434), with fellowship code LCF/BQ/PI19/11690015, and the support of the Spanish Agencia Estatal de Investigacion through the grant "IFT Centro de Excelencia Severo Ochoa SEV-2016-0597". The work of CJM was financed by FEDER – Fundo Europeu de Desenvolvimento Regional funds through the COMPETE 2020 – Operational Programme for Competitiveness and Internationalisation (POCI), and by Portuguese funds through FCT - Fundação para a Ciência e a Tecnologia in the framework of the project POCI-01-0145-FEDER-028987. S.N. acknowledges support from the research project PGC2018-094773-B-C32, the Centro de Excelencia Severo Ochoa Program SEV-2016-059 and the Ramón y Cajal program through Grant No. RYC-2014-15843. D.S. acknowledges financial support from the Fondecyt Regular project number 1200171. I.T. acknowledges support from the Spanish Ministry of Science, Innovation and Universities through grant ESP2017-89838-C3-1-R, and the H2020 programme of the European Commission through grant 776247. A.A. acknowledges support from the Science and Technology Facilities Council (STFC) grant ST/P000703/1. V.Y. acknowledges funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (grant agreement No. 769130)
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In: Astropolitics: the international journal of space politics & policy, Volume 10, Issue 2, p. 126-151
ISSN: 1557-2943