50 results on '"Josef Schubert"'
Search Results
2. Simulation of Spatial Sensor Characteristics in the Context of the EnMAP Hyperspectral Mission.
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Karl Segl, Luis Guanter, Hermann Kaufmann, Josef Schubert, Stefan Kaiser, Bernhard Sang, and Stefan Hofer
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- 2010
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3. Die Transformation des deutschen Energiesystems aus der Perspektive der Bevölkerung
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Josef Schubert, Daniel Kurt, Meyer, Thomas, and Möst, Dominik
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- 2015
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4. Dimensioning adaptive optics for future VLTI projects
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Jean-Baptiste Le Bouquin, Dieter Lutz, Stefan Gillessen, Julien Woillez, Maximilian Haase, Christopher Mandla, F. Haussmann, Florentin Millour, Nikhil More, C. Rau, Olivier Lai, Fabien Patru, Thomas Ott, Josef Schubert, Senol Yazici, Michael Hartl, Marcel Carbillet, Frank Eisenhauer, T. Paumard, Ekkehard Wieprecht, European Southern Observatory (ESO), Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA), Max Planck Institute for Extraterrestrial Physics (MPE), and Max-Planck-Gesellschaft
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Very Large Telescope ,Computer science ,business.industry ,Astrophysics::Instrumentation and Methods for Astrophysics ,01 natural sciences ,7. Clean energy ,Deformable mirror ,law.invention ,[SDU.ASTR.IM]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM] ,010309 optics ,Telescope ,Interferometry ,Upgrade ,Observatory ,law ,0103 physical sciences ,Aerospace engineering ,business ,Adaptive optics ,010303 astronomy & astrophysics ,Dimensioning - Abstract
The European Southern Observatory gives the opportunity to develop new third generation instruments for the Very Large Telescope Interferometer. Therefore, adaptive optics systems need to be upgraded, either for NAOMI on a 1.8-m auxiliary telescope or for MACAO on a 8-m unit telescope. It enables to access to new science cases such as active galactic nuclei with the GRAVITY+ project. We study here the requirements of such AO upgrade by increasing the number of sub-apertures of the wave-front sensor and the number of actuators of the deformable mirror. We evaluate the needs for a high-Strehl mode in the visible and near infrared wavelengths in various conditions of observation. We present numerical simulations to quantify the performance. We show that a moderate upgrade of NAOMI, and a significant upgrade of MACAO can enable both better dynamic range and sensitivity with the VLTI.
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- 2020
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5. Wann kommt die Kostenwende bei der EEG-Umlage?
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Dominik Möst, Daniel Kurt Josef Schubert, Fabian Hinz, and Matthias Dierle
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020209 energy ,0202 electrical engineering, electronic engineering, information engineering ,02 engineering and technology ,010501 environmental sciences ,01 natural sciences ,0105 earth and related environmental sciences - Abstract
Die Umlage des Erneuerbaren-Energien-Gesetzes (EEG) macht heute einen wesentlichen Teil des Strompreises von Haushalts- und Gewerbekunden aus. Nachdem die Autoren den Wirkmechanismus des implementierten Umlageverfahrens, die historische Entwicklung sowie Fehleinschatzungen skizziert haben, wird im Beitrag insbesondere der Frage nachgegangen, ob und wann eine Reduktion der EEG-Umlage erwartet werden kann (Kostenwende). Fur die Ermittlung der EEG-Umlage wird ein Modell auf Basis der aktuellen Vergutungsregelungen des EEG herangezogen, welches anhand von Prognosen der Ubertragungsnetzbetreiber validiert wird. Die Berechnungen zeigen, dass im Referenzfall ab 2025 nach einem Anstieg der EEG-Umlage auf uber 8 ct/kWh ein Ruckgang erwartet werden kann. Im Rahmen von Sensitivitatsrechnungen werden verschiedene Unsicherheitsfaktoren identifiziert, wie die Entwicklung des Groshandelspreises oder der Vergutungssatze. Diese Unsicherheitsfaktoren beeinflussen die EEG-Umlage masgeblich und stellen somit eine Herausforderungen bei der Entwicklung einer verlasslichen Prognose dar.
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- 2018
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6. Analysis of the Potential Economic Viability of Shale Gas Resources in Europe
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Tim Gerald Riedel, Daniel Kurt Josef Schubert, Matthew Schmidt, Dominik Möst, and Philipp Hauser
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Engineering ,Petroleum engineering ,business.industry ,Shale gas ,Natural resource economics ,020209 energy ,05 social sciences ,02 engineering and technology ,Boom ,050601 international relations ,0506 political science ,Economic viability ,Natural gas ,0202 electrical engineering, electronic engineering, information engineering ,Production (economics) ,Energy supply ,business ,Cost calculation ,Market conditions - Abstract
European countries are currently exploring strategies to ensure a strong level of security of energy supply while decreasing its reliance on natural gas imports. With the strong surge in shale gas developments in the USA, similar ambitions have been the ongoing subject of inquiry in Europe. Detailed knowledge about extraction costs is a key issue in determining future shale gas investments in Europe. The paper at hand analyses the potential of European shale gas resources, highlighting their competitiveness against conventional natural gas. It examines the current volume of shale gas resources in Europe and performs a detailed cost calculation to provide an estimation of shale gas production costs. The results indicate that under current market conditions the repetition of the US shale gas boom is by all measures improbable in Europe. Furthermore, in the case that natural prices were to return to historically higher levels, only a few highly productive shale gas formations would be economically competitive.
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- 2017
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7. The MICADO first light imager for ELT: cold optics instrument
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R. Davis, N. Ageorges, V. Garrel, Christopher Mandla, Hans Gemperlein, Eckhard Sturm, Sebastian Rabien, Veronika Hörmann, L. Barl, D. Kampf, Norbert Geis, Michael Hartl, R. Rüddenklau, J. Ziegleder, M. Manhart, and Josef Schubert
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Physics ,Spectrometer ,business.industry ,Optical instrument ,First light ,01 natural sciences ,law.invention ,010309 optics ,Optics ,Cardinal point ,Laser guide star ,law ,0103 physical sciences ,Extremely Large Telescope ,business ,Adaptive optics ,010303 astronomy & astrophysics ,Coronagraph - Abstract
MICADO, the Multi-AO-Imaging-Camera and Spectrometer for Deep Observations, is one of the first light instruments for the future 40 m class Extremely Large Telescope (ELT). MICADO utilizes the advanced laser guide star multiconjugate adaptive optics system MCAO developed by the MAORY consortium and the jointly developed singleconjugate adaptive optics system (SCAO). We present an overview on the conceptual design of the MICADO Cold Optical Instrument (COI) which comprises the infrared focal plane imager with its 3 x 3 4k2 HgCdTe detector array and a compact cross-dispersing slit spectrometer operating in the spectral range of 0.8 to 2.4 μm. High contrast imaging is enabled via a classical configuration of coronagraph and Lyot stops. The paper summarizes the MICADO COI interchangeable optics, its cryogenic implementation together with the modular opto-mechanical configuration of the cryo-mechanisms and the cryo-vacuum cooling system, which consists of a continuous LN2 flow cryostat.
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- 2018
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8. The MICADO first-light imager for the ELT: towards the preliminary design review of the MICADO-MAORY SCAO
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Emiliano Diolaiti, Sébastien Durand, Napoléon Nguyen-Tuong, Michael Hartl, Fabrice Vidal, D. Gratadour, C. Perrot, Paolo Ciliegi, Jean-Michel Huet, Eric Gendron, Mathieu Cohen, Vincent Déo, Vincent Chambouleyron, Gérard Rousset, Gérard Zins, Richard Davies, Julien Gaudemard, Youssef Younes, F. Chapron, Florian Ferreira, Lorenzo Busoni, Olivier Dupuis, Arnaud Sevin, Simone Esposito, Josef Schubert, Yann Clénet, Pierre Baudoz, Tristan Buey, Elsa Huby, Philippe Feautrier, P. Fédou, Saber Ben Nejma, Bertrand Le Ruyet, Bruno Borgo, Veronika Hörmann, Z. Hubert, Simone Thijs, Gaële Barbary, ITA, FRA, and DEU
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Wavefront ,business.industry ,Computer science ,Control software ,First light ,Wavefront sensor ,Dichroic glass ,01 natural sciences ,law.invention ,010309 optics ,Telescope ,Optics ,law ,0103 physical sciences ,Guide star ,business ,Adaptive optics ,010303 astronomy & astrophysics - Abstract
MICADO is the European ELT first-light imager, working in the near-infrared at the telescope diffraction limit. Provided by MAORY, the ELT first-light adaptive optics module (AO), MCAO will be the primary AO mode of MICADO, driving the design of the instrument. MICADO will also come with a SCAO capability. Developed under MICADO’s responsibility and jointly by MICADO and MAORY, SCAO will be the first AO mode to be tested at the telescope, in a phased approach of the AO integration at the ELT. The MICADO-MAORY SCAO preliminary design review (PDR) will occur in November 2018. We present here different activities and results we have had in the past two years preparing this PDR, covering several fields (opto-mechanics, electronics, real-time and control software, integration and tests, AO simulations and performance, prototyping) and the different SCAO subsystems (pyramid wavefront sensor, calibration unit, real-time computer, dichroic and the so-called Green Doughnut which hosts the SCAO assembly as well as the MAORY MCAO natural guide star wavefront sensors).
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- 2018
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9. Does political and social feasibility matter in energy scenarios?
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Daniel Kurt Josef Schubert, Sebastian Thuß, and Dominik Möst
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Renewable Energy, Sustainability and the Environment ,Management science ,Process (engineering) ,Energy (esotericism) ,Energy Engineering and Power Technology ,Legislature ,Energy transition ,Fuel Technology ,Investment decisions ,Nuclear Energy and Engineering ,Risk analysis (engineering) ,Political system ,Transparency (graphic) ,Economics ,Normative ,Social Sciences (miscellaneous) - Abstract
Scenarios have become an influential tool in the process of energy system transitions, as they form a basis for, e.g., investment decisions or legislative frameworks. In this respect, researchers have recently focused on the technological viability of normative targets (e.g., emissions reduction). Beyond that sufficient condition, experience has shown that missing social acceptance may serve as a severe hurdle to the actual implication. Furthermore, the functional principles of the surrounding political system may prove inconsistent with the scenario's assumptions or implications. As a contribution to scenario methodology, this paper presents an analytic framework with a focus on the German energy transition. Accounting for transparency, social acceptance and political feasibility, future energy scenarios might be inclined to be more mindful of societal limitations. These hurdles may range from subjectively ascribed characteristics of the energy system to political veto-players. While the analytic framework is applied, it is not limited to the four recent energy scenarios published by German public actors. This study's results highlight the need for an advanced scenario construction process, which becomes eminent given that the emphasis is currently moving from if an energy transition is possible to how this goal can be achieved.
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- 2015
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10. The MICADO first light imager for the ELT: overview, operation, simulation
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Joao Alves, Davide Massari, Maximilian Fabricius, Wilfried Boland, O. Dupuis, R.-R. Rohloff, Piercarlo Bonifacio, Sebastian Rabien, U. Neumann, M. Manhart, Gérard Rousset, N. M. Förster Schreiber, Hans Gemperlein, Eckhard Sturm, Florian Lang-Bardl, Josef A. Richter, Roberto Ragazzoni, Florian Kerber, V. Hörmann, Arnaud Sevin, Matthias Rosensteiner, Suzanne Ramsay, Ralf Bender, Ronny Ramlau, Kieran Leschinski, M. Hauser, Peter Bizenberger, R. Genzel, B. Borgo, H.-J. Hess, Vincent Garrel, Markus Plattner, K. Disseau, J. M. Huet, A. Monna, L. Barl, Jens Thomas, Willem Jellema, P. Baudoz, Bodo L. Ziegler, Martin Glück, Christopher Mandla, Niels Tromp, Tristan Buey, Stefan Dreizler, J. Schlichter, Ulrich Hopp, Eline Tolstoy, Ramón Navarro, Stefan Gillessen, Frank Grupp, N. Muench, E. Huby, Simona Mei, H. W. Rix, J. Ramos, Wolfgang Kausch, F. Merlin, Mathieu Cohen, D. Ives, P. Rhode, Roland Wagner, P. Fedou, Gérard Zins, Josef Schubert, Fabrice Vidal, G. Musters, F. Chapron, Renato Falomo, Naidu Bezawada, H. Kravcar, Michael Wegner, Santiago Barboza, Amon Richter, Lars Mohr, Remko Stuik, G. Rodeghiero, G. Verdoes-Kleijn, Harald Nicklas, Paola Amico, A. Janssen, J. Ziegleder, Victoria Hutterer, Norbert Przybilla, W. Zeilinger, N. Neumayer, Ralph Hofferbert, Eric Gendron, F. Müller, Jörg-Uwe Pott, H. Anwand-Heerwart, O. Czoske, Michael Hartl, Fanny Chemla, B. Le Ruyet, Z. Hubert, Yann Clénet, Ric Davies, Jenny Niebsch, N. Geis, V. Déo, Astronomy, and ITA
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High contrast ,Computer science ,Data simulation ,FOS: Physical sciences ,Astrometry ,First light ,Object (computer science) ,01 natural sciences ,010309 optics ,0103 physical sciences ,Systems engineering ,Focus (optics) ,Instrument design ,Adaptive optics ,Astrophysics - Instrumentation and Methods for Astrophysics ,010303 astronomy & astrophysics ,Instrumentation and Methods for Astrophysics (astro-ph.IM) - Abstract
MICADO will enable the ELT to perform diffraction limited near-infrared observations at first light. The instrument's capabilities focus on imaging (including astrometric and high contrast) as well as single object spectroscopy. This contribution looks at how requirements from the observing modes have driven the instrument design and functionality. Using examples from specific science cases, and making use of the data simulation tool, an outline is presented of what we can expect the instrument to achieve., Comment: Proc SPIE 10702. SPIE's copyright notice: "Copyright 2018 Society of PhotoOptical Instrumentation Engineers. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper are prohibited."
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- 2018
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11. ERIS: revitalising an adaptive optics instrument for the VLT
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Helmut Feuchtgruber, H. M. Schmid, Jonas Kühn, Eckhard Sturm, M. Deysenroth, Matthew A. Kenworthy, Marco Xompero, B. Briguglio, Guido Agapito, Jeroen Heijmans, R. Genzel, Alfio Puglisi, Stephen March, N. M. Förster Schreiber, Hans Gemperlein, A. Valentini, Mark Neeser, Giovanni Cresci, Christophe Giordano, Christoph U. Keller, David Henry, A. Boehle, Michael Hartl, Stefan Gillessen, Valdemaro Biliotti, D. Ferruzzi, David Pearson, David Lunney, Polychronis Patapis, Simone Esposito, David S. Doelman, Markus Plattner, Armando Riccardi, Elizabeth George, A. Agudo Berbel, Josef Schubert, Chris Waring, Harald Kuntschner, A. Di Cianno, Paolo Grani, Frank Eisenhauer, Ric Davies, Erich Wiezorrek, F. Mannucci, J. F. Lightfoot, Reinhold J. Dorn, Bernardo Salasnich, A. Buron, C. Rau, Frans Snik, Beth Biller, Andreas Glindemann, A. Cortes, Martin Black, Xiaofeng Gao, Daniela Fantinel, Sascha P. Quanz, H. Huber, G. Di Rico, M. Kasper, Luca Carbonaro, Adrian M. Glauser, William Taylor, Mike MacIntosh, Andrea Baruffolo, and Mauro Dolci
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Wavefront ,biology ,Design review (U.S. government) ,Computer science ,media_common.quotation_subject ,Astrophysics::Instrumentation and Methods for Astrophysics ,FOS: Physical sciences ,Astrometry ,Astrophysics::Cosmology and Extragalactic Astrophysics ,biology.organism_classification ,01 natural sciences ,Exoplanet ,010309 optics ,Sky ,0103 physical sciences ,Systems engineering ,Astrophysics::Earth and Planetary Astrophysics ,Adaptive optics ,Focus (optics) ,Astrophysics - Instrumentation and Methods for Astrophysics ,010303 astronomy & astrophysics ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,Eris ,media_common - Abstract
ERIS is an instrument that will both extend and enhance the fundamental diffraction limited imaging and spectroscopy capability for the VLT. It will replace two instruments that are now being maintained beyond their operational lifetimes, combine their functionality on a single focus, provide a new wavefront sensing module that makes use of the facility Adaptive Optics System, and considerably improve their performance. The instrument will be competitive with respect to JWST in several regimes, and has outstanding potential for studies of the Galactic Center, exoplanets, and high redshift galaxies. ERIS had its final design review in 2017, and is expected to be on sky in 2020. This contribution describes the instrument concept, outlines its expected performance, and highlights where it will most excel., 12 pages, Proc SPIE 10702 "Ground-Based and Airborne Instrumentation for Astronomy VII"
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- 2018
12. MICADO: the camera support structure at the E-ELT Nasmyth focus
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Harald Nicklas, H. Anwand-Heerwart, P. Rhode, and Josef Schubert
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Structure (mathematical logic) ,Wavefront ,Focus (computing) ,business.industry ,Computer science ,02 engineering and technology ,First light ,021001 nanoscience & nanotechnology ,01 natural sciences ,010309 optics ,Mode (computer interface) ,0103 physical sciences ,0210 nano-technology ,business ,Computer hardware ,Simulation - Abstract
MICADO is one of the first light instruments at the E-ELT and is designed to work with the MCAO system MAORY. The ability to operate in a stand-alone mode without MAORY includes an additional SCAO wavefront sensing system. Therefore, the instrument support structure has to fulfil two purposes, a) the positioning of the camera in its stand-alone mode and b) when it will be mounted downstream of the MCAO facility MAORY. The instrument support structure of MICADO is addressed regarding its basic functionalities such as passive and possible active positioning of the instrument. Very first FEA results will be given as well as other performance assessments.
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- 2016
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13. Joint MICADO-MAORY SCAO mode: specifications, prototyping, simulations and preliminary design
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Laura Schreiber, Lorenzo Busoni, Zoltan Hubert, F. Chapron, Emiliano Diolaiti, Arnaud Sevin, Damien Gratadour, Matteo Lombini, Marco Bonaglia, Gerard Rousset, Fabrice Vidal, C. Perrot, Eric Gendron, Mathieu Cohen, Simone Esposito, Pierre Baudoz, Yann Clénet, Richard Davies, Fanny Chemla, Paolo Ciliegi, Armando Riccardi, Tristan Buey, G. Zins, Sébastien Durand, Josef Schubert, Florian Ferreira, Alexis Carlotti, Philippe Feautrier, Nicolas Doucet, 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), Haute résolution angulaire en astrophysique, Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-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)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Technique, ITA, FRA, and DEU
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Diffraction ,Computer science ,Mode (statistics) ,Wavefront sensor ,01 natural sciences ,law.invention ,010309 optics ,Telescope ,law ,0103 physical sciences ,Adaptive optics ,Joint (audio engineering) ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,010303 astronomy & astrophysics ,Simulation - Abstract
MICADO is the E-ELT first-light imager, working at the diffraction limit in the near-infrared. Multi-conjugate adaptive optics (MCAO) will be the primary AO mode of MICADO, driving the design of the instrument. It will be provided by MAORY, the E-ELT first-light AO module. MICADO will also come with a SCAO capability, jointly developed by MICADO and MAORY. SCAO will be the first AO mode to be tested at the telescope, in a phased approach of AO integration at the E-ELT. We present in the following the MICADO-MAORY SCAO specifications, the current SCAO prototyping activities at LESIA for E-ELT scale pyramid wavefront sensor (WFS) and real-time computer (RTC), our activities on end-to-end AO simulations and the current preliminary design of SCAO subsystems. We finish by presenting the implementation and current design studies for the high-contrast imaging mode of MICADO, which will make use of the SCAO correction offered to the instrument.
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- 2016
14. ERIS: preliminary design phase overview
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Martin Brinkmann, Luca Fini, Andrea Modigliani, Paola Amico, Erich Wiezorrek, Elena Valenti, Giovanni Cresci, Markus Plattner, Gianluca Di Rico, Barbara Klein, Adrian M. Glauser, Carmelo Arcidiacono, Eckhard Sturm, Marco Xompero, Harald Weisz, Mauro Dolci, Michael Meyer, Gert Finger, R. Brast, Runa Briguglio, Florian Kerber, Reiner Hofmann, Michael Hartl, Guido Agapito, Lars Lundin, Armando Riccardi, Frank Eisenhauer, Karl Tarantik, Enrico Pinna, Harald Kuntschner, Elisabeth M. George, Marco Bonaglia, Alfio Puglisi, Josef Schubert, Enrico Marchetti, Helmut Feuchtgruber, Michel Duchateau, Enrico Fedrigo, Luca Carbonaro, Bernard Delabre, Miska Le Louarn, Jacopo Antichi, Fernando Gago Rodriguez, Matteo Accardo, Mark Neeser, M. Müller, Sascha P. Quanz, H. Huber, Simone Esposito, Fernando Quiros-Pacheco, Ralf Conzelmann, Sebastien Tordo, Valdemaro Biliotti, Christoph Frank, Johannes K. Dekker, Lieselotte Jochum, and J. Knudstrup
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Physics ,biology ,business.industry ,Strehl ratio ,Cassegrain reflector ,Wavefront sensor ,biology.organism_classification ,Laser guide star ,Optics ,Secondary mirror ,Adaptive optics ,business ,Spectrograph ,Eris - Abstract
The Enhanced Resolution Imager and Spectrograph (ERIS) is the next-generation adaptive optics near-IR imager and spectrograph for the Cassegrain focus of the Very Large Telescope (VLT) Unit Telescope 4, which will soon make full use of the Adaptive Optics Facility (AOF). It is a high-Strehl AO-assisted instrument that will use the Deformable Secondary Mirror (DSM) and the new Laser Guide Star Facility (4LGSF). The project has been approved for construction and has entered its preliminary design phase. ERIS will be constructed in a collaboration including the MaxPlanck Institut fur Extraterrestrische Physik, the Eidgenossische Technische Hochschule Zurich and the Osservatorio Astrofisico di Arcetri and will offer 1 – 5 μm imaging and 1 – 2.5 μm integral field spectroscopic capabilities with a high Strehl performance. Wavefront sensing can be carried out with an optical high-order NGS Pyramid wavefront sensor, or with a single laser in either an optical low-order NGS mode, or with a near-IR low-order mode sensor. Due to its highly sensitive visible wavefront sensor, and separate near-IR low-order mode, ERIS provides a large sky coverage with its 1’ patrol field radius that can even include AO stars embedded in dust-enshrouded environments. As such it will replace, with a much improved single conjugated AO correction, the most scientifically important imaging modes offered by NACO (diffraction limited imaging in the J to M bands, Sparse Aperture Masking and Apodizing Phase Plate (APP) coronagraphy) and the integral field spectroscopy modes of SINFONI, whose instrumental module, SPIFFI, will be upgraded and re-used in ERIS. As part of the SPIFFI upgrade a new higher resolution grating and a science detector replacement are envisaged, as well as PLC driven motors. To accommodate ERIS at the Cassegrain focus, an extension of the telescope back focal length is required, with modifications of the guider arm assembly. In this paper we report on the status of the baseline design. We will also report on the main science goals of the instrument, ranging from exoplanet detection and characterization to high redshift galaxy observations. We will also briefly describe the SINFONI-SPIFFI upgrade strategy, which is part of the ERIS development plan and the overall project timeline.
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- 2014
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15. Simulation of spatial sensor characteristics in the context of the EnMAP Hyperspectral mission
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Bernhard Sang, Luis Guanter, Stefan Kaiser, Hermann Kaufmann, Karl Segl, S. Hofer, and Josef Schubert
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Earth observation ,Computer science ,Distortion (optics) ,Hyperspectral imaging ,550 - Earth sciences ,Context (language use) ,Solid modeling ,Reflectivity ,Multidimensional signal processing ,EnMAP ,General Earth and Planetary Sciences ,Institut für Geowissenschaften ,Electrical and Electronic Engineering ,Remote sensing - Abstract
The simulation of remote sensing images is a valuable tool for defining future Earth observation systems, optimizing instrument parameters, and developing and validating data-processing algorithms. A scene simulator for optical Earth observation data has been developed within the Environmental Mapping and Analysis Program (EnMAP) hyperspectral mission. It produces EnMAP-like data following a sequential processing approach consisting of five independent modules referred to as reflectance, atmospheric, spatial, spectral, and radiometric modules. From a modeling viewpoint, the spatial module is the most complex. The spatial simulation process considers the satellitetarget geometry, which is adapted to the EnMAP orbit and operating characteristics, the instrument spatial response, and the sources of spatial nonuniformity (keystone, telescope distortion and smile, and detector coregistration). The spatial module of the EnMAP scene simulator is presented in this paper. The EnMAP spatial and geometric characteristics will be described, the simulation methodology will be presented in detail, and the capability of the EnMAP simulator will be shown by illustrative examples. © 2006 IEEE.
- Published
- 2010
16. AsteroidFinder - The Space-Borne Telescope to Search for NEO Asteroids
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Herbert Mosebach, Josef Schubert, Michael Hartl, Stefano Mottola, Harald Michaelis, Karsten Schindler, and Ekkehard Kührt
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Physics ,Point spread function ,Zodiacal light ,asteroid ,Aperture ,business.industry ,Exit pupil ,Stray light ,Astrophysics::Instrumentation and Methods for Astrophysics ,Astronomy ,Field of view ,telescope ,AsteroidFinder/SSB ,IEO ,law.invention ,Cesic ,Telescope ,Optics ,Limiting magnitude ,law ,Astrophysics::Earth and Planetary Astrophysics ,AsteroidFinder ,business ,SSB - Abstract
This paper presents the mission profile as well as the optical configuration of the space-borne AsteroidFinder telescope. Its main objective is to retrieve asteroids with orbits interior to Earth’s orbit. The instrument requires high sensitivity to detect asteroids with a limiting magnitude of equal or larger than 18.5mag (V-Band) and astrometric accuracy of 1arcsec (1σ). This requires a telescope aperture greater than 400cm², high image stability, detectors with high quantum efficiency (peak > 90%) and very low noise, which is only limited by zodiacal background. The telescope will observe the sky between 30° and 60° in solar elongation. The telescope optics is based on a Cook type TMA. An effective 2°×2° field of view (FOV) is achieved by a fast F/3.4 telescope with near diffraction-limited performance. The absence of center obscuration or spiders in combination with an accessible intermediate field plane and exit pupil allow for efficient stray light mitigation. Design drivers for the telescope are the required point spread function (PSF) values, an extremely efficient stray light suppression (due to the magnitude requirement mentioned above), the detector performance, and the overall optical and mechanical stability for all orientations of the satellite. To accommodate the passive thermal stabilization scheme and the necessary structural stability, the materials selection for the telescope main structure and the mirrors are of vital importance. A focal plane with four EMCCD detectors is envisaged. The EMCCD technology features shorter integration times, which is in favor regarding the pointing performance of the satellite. The launch of the mission is foreseen for the year 2013 with a subsequent mission lifetime of at least 1 year.
- Published
- 2010
17. NbN hot electron bolometric mixers at frequencies between 0.7 and 3.1 THz
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Matthias Kroug, Harald Franz Arno Merkel, Heinz-Wilhelm Hübers, Josef Schubert, Erik L. Kollberg, and Pavel A. Yagoubov
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Physics ,Spiral antenna ,Noise temperature ,business.industry ,Terahertz radiation ,Local oscillator ,Far-infrared laser ,Bolometer ,Metals and Alloys ,Condensed Matter Physics ,law.invention ,Optics ,Intermediate frequency ,law ,Materials Chemistry ,Ceramics and Composites ,Heterodyne detection ,Electrical and Electronic Engineering ,business - Abstract
The performance of NbN-based phonon-cooled hot electron bolometric (HEB) quasioptical mixers is investigated in the 0.7-3.1 THz frequency range. The devices are made from a 3.5-4 nm thick NbN film on high resistivity Si and integrated with a planar spiral antenna on the same substrate. The length of the bolometer microbridge is 0.1-0.2 µm; the width is 1-2 µm. The best results of the DSB receiver noise temperature measured at 1.5 GHz intermediate frequency are: 800 K at 0.7 THz, 1100 K at 1.6 THz, 2000 K at 2.5 THz and 4200 K at 3.1 THz. The measurements were performed with a far infrared laser as the local oscillator (LO) source. The estimated LO power requirement is less than 500 nW at the receiver input. First results on spiral antenna polarization measurements are reported.
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- 1999
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18. Compact prism spectrometer of pushbroom type for hyperspectral imaging
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Bernhard Sang, Timo Stuffler, Josef Schubert, Stefan Hofer, and Stefan Kaiser
- Subjects
Diffraction ,Physics ,Optics ,Spectrometer ,business.industry ,Imaging spectrometer ,EnMAP ,Physics::Optics ,Hyperspectral imaging ,Prism ,Grating ,business ,Diffraction efficiency - Abstract
Imaging spectrometers featuring a grating disperser allow for a compact system design. However, due to the limited diffraction efficiency of the grating these instruments suffer from low throughput and high sensitivity to polarization. Prism spectrometers do not have these disadvantages, but they show a low angular dispersion with noticeable non-linearity, which is the main driver of the overall spectrometer dimensions. The envelope of a prism spectrometer can be significantly decreased when prisms with curved surfaces are used. They allow for a reconfiguration of the concentric Offner relay which is well known for its good imaging quality and its low distortion. In the document at hand a novel type of compact Offner spectrometers with curved prisms is presented. As an example the optic design of EnMAP, a German space born hyperspectral imager is given.
- Published
- 2008
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19. Characterization of high- and low-stressed Ge:Ga array cameras for Herschel's PACS instrument
- Author
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L. Barl, Jürgen Schreiber, Dietrich Lemke, Reinhard O. Katterloher, Josef Schubert, Albrecht Poglitsch, Hilmar Richter, Stephan M. Birkmann, Katja Eberle, and Ulrich Grözinger
- Subjects
Physics ,Cryostat ,Spectrometer ,business.industry ,Detector ,law.invention ,Telescope ,Responsivity ,Optics ,Observational astronomy ,Black body ,law ,Optoelectronics ,business ,Image resolution - Abstract
The Herschel Space Observatory is a passively cooled 3.5 m telescope (Tmirror < 90 K) scheduled for launch in 2007. One of its three scientific instruments is PACS (Photoconductor Array Camera and Spectrometer) which will carry out astronomical observations in the wavelength range of 57 μm to 210 μm with unprecedented sensitivity and spatial resolution. PACS has two cameras for imaging spectroscopy in two wavelength bands from 57 μm to 130 μm and 130 μm to 210 μm. Both cameras are built up from 25 linear arrays, each with 16 detector pixels consisting of Gallium doped Germanium crystals. By stressing these crystals with a boltspring mechanism, the desired cut-off wavelengths of ~ 127 μm and ~ 205 μm can be reached. The detectors are operated at temperatures of ~ 2 K and read out by cryogenic readout electronics (CRE), featuring preamplifiers and multiplexers. Test facilities have been designed and built up at MPIA, Heidelberg, and MPE, Garching, in order to characterize and calibrate the spectrometer cameras before integration into the instrument. Both test facilities have a cryostat cooled by superfluid liquid helium. While the MPE facility uses an internal cold black body to illuminate the camera, the facility at MPIA makes use of an external black body and cold attenuation filters. Tests of the qualification models of the spectrometer cameras show that the detector responsivity is ~ 8 A/W and ~ 40 A/W for the low and high stressed detectors respectively, surpassing the requirements. The NEP is currently limited by CRE readout noise and will be improved with the new generation of FM CREs. Ionizing irradiation significantly increases the detector responsivity, which might make it necessary to operate them with a lower bias voltage. On the other hand, radiation effects can be reliably cured by a combination of bias boosts and infrared flashes.
- Published
- 2004
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- View/download PDF
20. NbN Hot Electron Bolometer as THz Mixer for SOFIA
- Author
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H.-W. Huebers, Gregory Goltsman, E. M. Gershenzon, Alfred Krabbe, A. D. Semenov, Hans-Peter Roeser, Boris M. Voronov, and Josef Schubert
- Subjects
Heterodyne ,Physics ,hot-electron bolometer ,business.industry ,Terahertz radiation ,Superheterodyne receiver ,Bolometer ,heterodyne receiver ,Radiation pattern ,law.invention ,terahertz ,Optics ,superconductor ,law ,NbN ,Double-sideband suppressed-carrier transmission ,Optoelectronics ,Antenna (radio) ,business ,SOFIA ,Noise (radio) ,mixer - Abstract
Heterodyne receivers for applications in astronomy need quantum limited sensitivity. We have investigated phonon- cooled NbN hot electron bolometric mixers in the frequency range from 0.7 THz to 5.2 THz. The devices were 3.5 nm thin films with an in-plane dimension of 1.7 X 0.2 micrometers 2 integrated in a complementary logarithmic spiral antenna. The best measured DSB receiver noise temperatures are 1300 K (0.7 THz), 2000 K (1.4 THz), 2100 K (1.6 THz), 2600 K (2.5 THz), 4000 K (3.1 THz), 5600 K (4.3 THz), and 8800 K (5.2 THz). The sensitivity fluctuation, the long term stability, and the antenna pattern were measured. The results demonstrate that this mixer is very well suited for GREAT, the German heterodyne receiver for SOFIA.
- Published
- 2000
21. NbN phonon-cooled hot-electron bolometer as a mixer for THz heterodyne receivers
- Author
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Boris M. Voronov, Josef Schubert, Eugeni M. Gershenzon, A. Semenov, Gerhard Schwaab, G. Gol'tsman, and H.-W. Huebers
- Subjects
Spiral antenna ,Heterodyne ,Physics ,business.industry ,Terahertz radiation ,Superheterodyne receiver ,Bolometer ,law.invention ,Radiation pattern ,Optics ,law ,Double-sideband suppressed-carrier transmission ,Optoelectronics ,business ,Noise (radio) - Abstract
We have investigated a phonon-cooled NbN hot electron bolometric (HEB) mixer in the frequency range from 0.7 THz to 5.2 THz. The device was a 3.5 nm thin film with an in-plane dimension of l.7x0.2 jtm2 integrated in a complementarylogarithmic spiral antenna. The measured DSB receiver noise temperatures are 1500 K (0.7 THz), 2200 K (1.4 THz), 2600 K(1 .6 THz), 2900 K (2.5 THz), 4000 K (3.1 THz), 5600 K (4.3 THz), and 8800 K (5.2 THz). The sensitivity fluctuation, thelong term stability, and the antenna pattern were measured and the suitability of the mixer for a practical heterodyne receiver is discussed. Keywords: hot-electron bolometer, NbN, superconductor, mixer, terahertz, spiral antenna 1. INTRODUCTION High resolution heterodyne spectroscopy in the frequency range from 1 THz to 6 THz yields important information onastronomical objects as well as the atmosphere of the earth. Some prominent examples are the CII fine structure line at1 .6 THz and the 01 fme structure line at 4.75 THz
- Published
- 1999
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22. ISOPHOT: in-flight performance report
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L. Cornwall, Manfred Stickel, C. Gabriel, U. Herbstmeier, J. A. Acosta Pulido, P. Ábrahám, Josef Schubert, Martin Haas, Ulrich Groezinger, Ulrich Klaas, Dietrich Lemke, Bernhard Schulz, Ingolf Heinrichsen, L. V. Toth, and Héctor O. Castañeda
- Subjects
Physics ,business.industry ,Stray light ,media_common.quotation_subject ,Astrophysics::Instrumentation and Methods for Astrophysics ,Near and far field ,Cosmic ray ,Radiation ,symbols.namesake ,Optics ,Optical path ,Sky ,Van Allen radiation belt ,symbols ,business ,Optical filter ,media_common ,Remote sensing - Abstract
The imaging photopolarimeter ISOPHOT on-board the European satellite ISO houses 144 background detectors of Si:Ga, Si:P, Ge:Ga and stressed Ge:Ga, all sampled by newly developed cold read-out electronics. There is large temporal radiation damage to most of these detectors on the daily passage through the earth's radiation belts. In addition the Ge:Ga detectors exhibit a continuous responsivity increase caused by the cosmic radiation far off the earth. Effective curing procedure shave been developed to heat out these effects. The in-flight sensitivities achieved are close to the pre-flight predictions for most channels. At 100-200 micrometers cirrus confusion is a serious limit for the detection of faint objects on large parts of the sky. The cold filter wheel carrying 56 optical elements, such as filters, apertures and polarizers, as well as the focal plane chopper, operate with high precision and very low power consumption. Due to an effective cold internal baffle system the measured near-field straylight was close to the pre- flight theoretical prediction based on APART simulations. THe sun and moon straylight at 25 and 175 micrometers was measured during several solar eclipses. Drift and transients of the detectors, non-linearities of the preamplifiers, ionizing radiation effects and a complex optical path make the photometric calibration of this instrument challenging. Because most of these effects are reproducible, a calibration accuracy of < 30 percent is already available for most photometric modes. Examples of observations, including the 175 micrometers Serendipitous Sky Survey, will highlight the capabilities of the instrument.
- Published
- 1998
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23. Infrared straylight measurements of the ISO telescope
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Manfred Stickel, Ulrich Klaas, Dietrich Lemke, Josef Schubert, L. V. Toth, T. Kranz, C. Leinert, and René J. Laureijs
- Subjects
Physics ,Stray light ,Infrared ,media_common.quotation_subject ,Astrophysics::Instrumentation and Methods for Astrophysics ,Astronomy ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Space observatory ,law.invention ,Telescope ,Stars ,Sky ,Planet ,law ,Astrophysics::Solar and Stellar Astrophysics ,Astrophysics::Earth and Planetary Astrophysics ,Surface brightness ,Astrophysics::Galaxy Astrophysics ,media_common - Abstract
Measurements were performed to verify the straylight suppression in the IR Space Observatory telescope using the ISOPHOT instrument. These test comprised the near-field straylight by bright stars and planets as well as the far- field straylight by the Sun, the Earth, and the Moon. No significant straylight above the specifications reflecting the astronomical needs for low surface brightness absolute sky measurements could be detected at 25 and 170 micrometers . In some cases comparison to preflight straylight simultaneous were possible. The consistency of the predictions from the models with the measurement results confirms the reasonable assumptions made for the simulations. This will allow to further optimize the telescope design for future low background IR space telescopes.
- Published
- 1998
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- View/download PDF
24. Low-resolution imaging spectroscopy with SOFIA
- Author
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Juergen Wolf, Josef Schubert, and Alfred Krabbe
- Subjects
Physics ,Infrared Astronomy ,Spectrometer ,business.industry ,Astrophysics::Instrumentation and Methods for Astrophysics ,Imaging spectrometer ,Infrared Spectroscopy ,Field of view ,Spica ,Imaging spectroscopy ,Optics ,Far infrared ,Observatory ,Spectral resolution ,business ,SOFIA ,Astrophysics::Galaxy Astrophysics ,Remote sensing - Abstract
LISA is the low resolution imaging spectrometer channel for SPICA. the proposed spectral-photometric-IR camera for the joint US and German stratospheric far IR observatory SOFIA. LISA will cover a spectral range from 40 micrometers to 220 micrometers at a spectral resolution (lambda) /(Delta) (lambda) approximately 22. It will record simultaneously individual diffraction limited spectra from several tens to several hundreds spatial positions of a rectangular field of view on the sky. A novel technical and optical solution will be presented for such an approach together with a brief discussion on the expected performance and possible astronomical applications.
- Published
- 1998
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25. Photoconductor arrays for a spectral-photometric far-infrared camera on SOFIA
- Author
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D. Rabanus, Juergen Wolf, Hans Driescher, E. Paul, Josef Schubert, and K. Roesner
- Subjects
Physics ,Infrared astronomy ,business.industry ,Stratospheric Observatory for Infrared Astronomy ,Photoresistor ,chemistry.chemical_element ,Germanium ,law.invention ,Telescope ,Optics ,Far infrared ,chemistry ,Observatory ,law ,Infrared detector ,business ,Remote sensing - Abstract
The Stratospheric Observatory for Infrared Astronomy, SOFIA, is a joint US and German project and will start observations from altitudes up to 45,000 ft in late 2001. The 2.5 m telescope is being developed in Germany while the 747- aircraft modifications and preparation of the observatory's operations center is done by a US consortium. Several research institutions and universities of both countries have started to develop science instruments. The DLR Institute of Space Sensor Technology in Berlin plans on a spectral-photometric camera working in the 20 to 220 micrometers wavelength range, using doped silicon and germanium extrinsic photoconductors in large, 2D arrays: silicon blocked-impurity band detectors, Ge:Ga and stressed Ge:Ga. While the silicon array will be commercially available, the germanium arrays have to be developed, including their cryogenic multiplexers. Partner institutions in Germany and the US will support the development of the instrument and its observations.
- Published
- 1998
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- View/download PDF
26. SPICA: a spectral-photometric infrared camera for SOFIA
- Author
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H. Anheyer, Juergen Wolf, Kevin Hanna, D. Rabanus, Alfred Krabbe, E. Paul, K. Roesner, Stefan Kirches, Hans Driescher, and Josef Schubert
- Subjects
Physics ,Infrared astronomy ,business.industry ,Infrared ,Detector ,infrared astronomy ,Cryogenics ,Spica ,law.invention ,Infrared instrumentation ,Telescope ,Optics ,Observatory ,law ,business ,Image resolution ,SOFIA ,Remote sensing - Abstract
The spectral-photometric IR camera SPICA is proposed as one of the German science instruments of the Stratospheric Observatory for IR Astronomy (SOFIA). It will cover a wavelength range of 20-220 micrometers with three large area detector arrays. With the 2.5 m SOFIA telescope, SPICA will provide unprecedented diffraction limited spatial resolution in the far-IR. In addition, low resolution 3D-imaging spectroscopy is planned. While the silicon array will be commercially available, the germanium arrays are being developed, including their cryogenic multiplexers. The overall instrument concept, its camera optics and the status of the detector development will be presented. The instrument is being developed by the DLR Institute of Space Sensor Technology in Berlin with support of several German and US partners.
- Published
- 1998
27. Si:As blocked-impurity-band detectors for ISO's photometer
- Author
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Dietrich Lemke, Juergen Wolf, Josef Schubert, Ulrich Groezinger, and Lorenz Wiest
- Subjects
Physics ,Infrared ,business.industry ,Detector ,Astrophysics::Instrumentation and Methods for Astrophysics ,Biasing ,Photometer ,law.invention ,Telescope ,Photometry (astronomy) ,Optics ,law ,Calibration ,Optoelectronics ,business ,Dark current - Abstract
ISOPHOT is one of the four focal plane instruments of the astronomical infrared space observatory (ISO). In its flight spare model the sensitivity of two photo-polarimeters could be significantly improved by replacing bulk Si:Ga and Si:B detectors by Si:As blocked impurity- band detectors. These detector elements were selected for low dark current to allow for low background observations in the LHe-cooled ISO telescope. Their operational parameters temperature and bias voltage were optimized for best sensitivity when operated with the ISOPHOT cryogenic readout electronics. At fluxes of about 10-16 W/pixel and temperatures of 2.9-3.6 K, NEPDET equals 5 X 10-18 W/Hz and R equals 23-36 A/W were measured. Their dynamic flux response is much faster than in bulk Si:Ga. Radiation-hardness has been tested by simulating the passage through the radiation belts on the ISO-orbit with a gamma source.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
- Published
- 1995
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28. Alpha-radiation tests on the transmission of cryogenically cooled infrared filter materials used in ISOPHOT
- Author
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K. Mampel, Dietrich Lemke, Wolfgang Kraetschmer, and Josef Schubert
- Subjects
Materials science ,Infrared ,business.industry ,Alpha particle ,Radiation ,engineering.material ,Optics ,Coating ,Far infrared ,engineering ,Optoelectronics ,Penetration depth ,business ,Optical filter ,Infrared cut-off filter - Abstract
We have studied potential effects of the ISO spacecraft orbital radiation environment on the transmission of infrared interference filters and filter materials. To simulate the critical proton radiation within the earth radiation belts and its influence on the materials at cryogenic temperatures the samples were cooled to LHe temperature and subjected to an Am-241 (alpha) -radiation source (approximately 4.1 MeV) mounted inside a cryostat. The dose per hour absorbed in a 20 micron thick layer, the mean penetration depth for the (alpha) particles, was about 25 krad (Si). The substrates Ge, ZnSe, and CaF2 and three tested ISOPHOT interference bandpass filters (3.21-3.37 micrometers and 2-50 micrometers even after a total dose of approximately 0.5 Mrad (Si), which is more than 100 times the expected total dose for ISOPHOT. The multilayer interference blocking coating on sapphire used on all ISOPHOT far infrared filters to block the wavelength range 1.7-6.7 micrometers showed no degeneration either. The organic far infrared antireflex coating materials polyethylene deposited on a quartz substrate, and a 15 micrometers thick parylene foil used as field lens coating, were investigated in the wavelength range of 16-300 micrometers . Our data suggests a slightly reduced transmission < 6% after 350 krad (Si) exposure.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
- Published
- 1995
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29. Precise theoretical description of photoresponse for detectors of ISOPHOT's Si:Ga array
- Author
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Boris I. Fouks and Josef Schubert
- Subjects
Physics ,business.industry ,Photoresistor ,Detector ,Flux ,Radiation ,law.invention ,Radiation flux ,Optics ,Semiconductor ,law ,Calibration ,Transient response ,business - Abstract
Low-background IR detectors have a very long-term transient response which, what is more, is highly dependent on the preceding irradiations. For these reasons to determine with a high precision the radiation flux of a cool space object, it has to be measured for a long time. The theory presented in this paper describes the detector operation under frequent flux changes and allows precise determination of the flux values from fast measurements, in spite of the strong memory effects. The theory is specialized for the ISOPHOT Si:Ga detector arrays and is confirmed by the experiments. Its use has to add to the productivity of the launched apparatus.
- Published
- 1995
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30. High-performance FIR bandpass filters for the ISOPHOT instrument
- Author
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Ernst Kreysa, Wolfgang Kraetschmer, Josef Schubert, and Hans-Peter Gemuend
- Subjects
Wavelength ,Engineering ,Transmission (telecommunications) ,Band-pass filter ,Filter (video) ,business.industry ,Electronic engineering ,Prototype filter ,Satellite ,Stopband ,business ,Passband - Abstract
The far-infrared filters for the satellite subexperiment ISOPHOT have to fulfil a number of specific requirements. This is a report about the developed filter concept which was used to match all specifications. In a wide wavelength region this concept is capable of defining broad or narrow bandpasses in a flexible way. The filters which have been constructed are robust and survive multiple cryogenic cycles. They combine high passband transmission with extreme stopband rejection. Details are given for some representative ISOPHOT FIR-filters.
- Published
- 1994
- Full Text
- View/download PDF
31. Correction and curing of in-orbit induced nonideal behavior of ISOPHOTS's photodetectors
- Author
-
Boris I. Fouks, Josef Schubert, Gabriele Roth, Dietrich Lemke, and Juergen Wolf
- Subjects
Physics ,Silicon ,Physics::Instrumentation and Detectors ,business.industry ,Infrared ,Detector ,Photodetector ,chemistry.chemical_element ,Germanium ,Radiation ,Optics ,chemistry ,Calibration ,Optoelectronics ,High Energy Physics::Experiment ,Irradiation ,business - Abstract
ISOPHOT, the photo-polarimeter on the Infrared Space Observatory (ISO) uses high sensitivity doped silicon and germanium photodetectors working in the wavelength range form 2.4 to 240 micrometers . Under low IR-background conditions such detectors show long and non-linear response relaxation to a step change of IR-illumination. We will show that this nonideal behavior can be described with high precision at least for the PHT-S Si:Ga detectors. In space, high- energy radiation will strongly influence the performance of the detectors operated a low temperature. Irradiation tests using a (gamma) -radiation source were performed on our Ge:Ga and stressed Ge:Ga detector simulating the radiation environment on the ISO orbit. We found annealing procedures for the detectors which restore the photometric calibrations to within a few percent.
- Published
- 1994
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- View/download PDF
32. ISOPHOT: the imaging photopolarimeter for the Infrared Space Observatory
- Author
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Juergen Wolf, Michael A. Patrashin, Dietrich Lemke, and Josef Schubert
- Subjects
Physics ,business.industry ,Detector ,Astronomy ,Orbital mechanics ,Radiation ,Responsivity ,symbols.namesake ,Optics ,Far infrared ,Van Allen radiation belt ,Calibration ,symbols ,Astrophysics::Earth and Planetary Astrophysics ,business ,Noise (radio) - Abstract
The flight model of ISOPHOT has been completed and delivered to ESA. The pre-flight calibration verified the high performance specifications for the far-infrared detector channels. At times, limiting factors in orbit may be high-energy-radiation induced noise and responsivity drifts after passage through the radiation belts, and signal drifts following large incident flux changes.
- Published
- 1993
- Full Text
- View/download PDF
33. ISOPHOT: far-infrared imaging, polarimetry, and spectrophotometry on Infrared Space Observatory
- Author
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Martyn Wells, Juergen Wolf, Josef Schubert, Peter Luetzow-Wentzky, Ingolf Heinrichsen, Dietrich Lemke, Ulrich Klaas, Wolfgang Kraetschmer, Hans-Peter Gemuend, Ulrich Groezinger, Ernst Kreysa, and Francisco Garzón
- Subjects
Physics ,Diffraction ,Infrared astronomy ,Solar System ,Far infrared ,Infrared ,Astrophysics::High Energy Astrophysical Phenomena ,Astrophysics::Instrumentation and Methods for Astrophysics ,Polarimetry ,Astronomy ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Spectral bands ,Optical filter - Abstract
ISOPHOT is one of four instruments onboard the ESA Infrared Space Observatory scheduled for launch in September 1995. It covers the wavelength range 2.5 micrometers to 240 micrometers with wide and marrow spectral bands. Diffraction limited observations as well as wide beam measurements of faint extended sources are possible. Polarimetric observation can be made over the whole wavelength range. The minimal detectable flux is approximately 10 mJy. The astronomical areas to be addressed range from solar system objects to cosmology.
- Published
- 1993
- Full Text
- View/download PDF
34. ISOPHOT calibration facility and pre-flight characterization
- Author
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Dietrich Lemke, Bernhard Schulz, Robert Wagner, Albrecht Frey, Klaus Proetel, I. L. Rasmussen, Clemens N. Tilgner, Josef Schubert, Stefan Kirches, Ingolf Heinrichsen, Juergen Wolf, Ulrich Groezinger, C. Gabriel, Manfred Boison, and G. A. Hirth
- Subjects
Physics ,Spectrometer ,business.industry ,Attenuation ,Astrophysics::Instrumentation and Methods for Astrophysics ,Orbital mechanics ,Optics ,Black body ,Acceptance testing ,Calibration ,Satellite ,business ,Optical filter ,Remote sensing - Abstract
A calibration facility simulating the optical and cryogenic environment of the ISO satellite has been built for characterizing the ISOPHOT instrument. This facility uses a commercially calibrated, 900 K--blackbody radiation source and an optics at room temperature to provide an f/15 beam to the instrument which is contained in a LHe-cryostat. The low level infrared flux levels of ISO are obtained by use of a light sealed instrument chamber and cold attenuation filters. The infrared flux can be calculated using the known blackbody emission and the cold calibrated transmission spectra of the filters. The calibration facility further provides a scanning mechanism, a light modulator and filters for polarization measurements and wavelength calibrations of the ISOPHOT spectrometer channels. Electrical support equipment for the instrument operation and software for data archiving and analysis have been customized for this project. The test program comprised a standardized acceptance test for the entire instrument and special tests addressing individual instrument properties. The data obtained contain the photometric sensitivities of ISOPHOT, optimized instrument settings, reference data for the integrated system tests and inputs for the ongoing mission planning.
- Published
- 1993
- Full Text
- View/download PDF
35. Die Transformation des deutschen Energiesystemsaus der Perspektive der Bevölkerung.
- Author
-
Josef Schubert, Daniel Kurt, Meyer, Thomas, and Möst, Dominik
- Abstract
Copyright of Zeitschrift für Energiewirtschaft is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2015
- Full Text
- View/download PDF
36. Calibration facility and preflight characterization of the photometer in the Infrared Space Observatory
- Author
-
Clemens N. Tilgner, Bernhard Schulz, Robert Wagner, Albrecht Frey, Juergen Wolf, Josef Schubert, Ingolf Heinrichsen, Klaus Proetel, I. L. Rasmussen, G. A. Hirth, Dietrich Lemke, Stefan Kirches, Ulrich Groezinger, Manfred Boison, and C. Gabriel
- Subjects
Physics ,Cryostat ,Spectrometer ,business.industry ,Astrophysics::Instrumentation and Methods for Astrophysics ,General Engineering ,Photometer ,Atomic and Molecular Physics, and Optics ,law.invention ,Optics ,law ,Black body ,Calibration ,Measuring instrument ,Satellite ,Optical filter ,business ,Remote sensing - Abstract
A calibration facility simulating the optical and cryogenic environment of the Infrared Space Observatory (ISO) satellite has been built for characterizing the ISO photometer (ISOPHOT). This facility uses a commercially calibrated 900-K blackbody radiation source and optics at room temperature to provide an f /15 beam to the instrument, which is contained in a LHe cryostat. The low-level infrared flux levels of the ISO are obtained by using a light-sealed instrument chamber and cold attenuation filters. The infrared flux can be calculated using the known blackbody emission and the cold calibrated transmission spectra of the filters. The calibration facility further provides a scanning mechanism, a light modulator, and filters for polarization measurements and wavelength calibrations of the ISOPHOT spectrometer channels. Electrical support equipment for the instrument operation and software for data archiving and analysis have been customized for this project. The test program comprised a standardized acceptance test for the entire instrument and special tests addressing individual instrument properties. The data obtained contain the photometric sensitivities of ISOPHOT, optimized instrument settings, reference data for the integrated system tests, and inputs for the ongoing mission planning.
- Published
- 1994
- Full Text
- View/download PDF
37. The Effect of Research with Teenage Mothers on the Development of Their Infants1
- Author
-
Jacquelin S. Montgomery, Josef Schubert, Sarah Landy, and John F. Cleland
- Subjects
Social Psychology ,Intervention (counseling) ,Strange situation ,Teenage mothers ,Psychology ,Social psychology ,Bayley Scales of Infant Development ,Developmental psychology - Abstract
Mother-infant interaction of 14 teenage mothers and 12 women 20 years or older was observed and recorded in the laboratory or the home when the infants were 16, 20, 24, and 52 weeks of age. In order to assess the possible effect of the research intervention on the maternal behavior and on the infants' development, a control group of teenage mothers and their infants was seen only at the end of the study when the infant was 52 weeks old. At 12 months the Home Observation Measure of the Environment Inventory (HOME) was administered and infants were assessed with the Bayley Scales of Infant Development (motor and mental scales) and the Ainsworth Strange Situation procedure. On all measures the observation groups scored significantly higher than the control group. The significant aspects of the research intervention are discussed.
- Published
- 1984
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38. Mother‐infant interaction of teenage mothers and the effect of experience in the observational sessions on the development of their infants
- Author
-
Josef Schubert, John F. Cleland, Camilla Clark, Sarah Landy, and Jacquelin S. Montgomery
- Subjects
Social Psychology ,Age differences ,Developmental and Educational Psychology ,Mother infant ,Strange situation ,Observational study ,Teenage mothers ,Psychology ,Pediatrics ,Bayley Scales of Infant Development ,Clinical psychology ,Developmental psychology - Abstract
Mother‐infant interaction of 14 teenage mothers and their infants was observed in the laboratory or in the home when the infant was 16, 20, 24 and 52 weeks of age. This behaviour was compared with that of 12 women 20 years or older and their infants. To control for experience in the observational sessions, a third similar comparative group of teenage mothers and their infants was also included in the study who were seen only at the end of the study when the infant was 52 weeks old. At 12 months the Home Observation Measurement of the Environment Inventory #opHOME#cp was administered and the infants were assessed with the Bayley Scales of Infant Development #opmotor and mental scales#cp and the Ainsworth Strange Situation procedure. Face‐to‐face interactions scores at 12 and 16 weeks of age were consistently better for the older mothers than the younger mothers. Teenagers showed few significant differences from older mothers in their mothering skills as measured in the home when the infant was 24 weeks of ...
- Published
- 1983
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- View/download PDF
39. MODELING OF AFFECTIONATE BEHAVIOR IN YOUNG CHILDREN
- Author
-
Josef Schubert and Michael Pirot
- Subjects
Nonverbal communication ,Affective behavior ,Social Psychology ,Affection ,media_common.quotation_subject ,Behavior change ,Psychology ,Imitation ,Social psychology ,Modelling ,media_common ,Developmental psychology - Abstract
A female experimenter modeled affectionate physical contact in a group of preschool children who imitated the behavior. This induced a significant increase of affectionate behavior during a subsequent free-play period. By contrast, a group which had imitated “neutral” physical contact and another that had imitated “warm” verbal contact did not show a significant increase in affectionate behavior. Aggressive behavior was virtually absent in all groups.
- Published
- 1977
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40. The VRB Apparatus: A Cross-Validation
- Author
-
Josef Schubert
- Subjects
Test battery ,medicine.medical_specialty ,05 social sciences ,050301 education ,050109 social psychology ,Audiology ,Training methods ,Cross-validation ,Developmental psychology ,medicine ,0501 psychology and cognitive sciences ,Psychology ,0503 education ,General Psychology - Abstract
Cross-validation data for a test for the investigation of verbal regulation of behavior (VRB; Schubert, 1969) were reported. The initial results were confirmed with a sample of 168 clinical Ss aged 2 to 15 yr. VRB scores were significantly related to age and intelligence ( p < .001). Split-half reliability of the final test battery was .92 ( N = 100) and the correlation between VRB scores and MA was .79 ( N = 84).
- Published
- 1970
- Full Text
- View/download PDF
41. The V.R.B. Apparatus: An Experimental Procedure for the Investigation of the Development of Verbal Regulation of Behavior
- Author
-
Josef Schubert
- Subjects
Intelligence Tests ,Research design ,Adolescent ,Verbal Behavior ,Intelligence ,Behavior change ,Age Factors ,Language acquisition ,Verbal learning ,Language Development ,Clinical Psychology ,Child, Preschool ,Intellectual Disability ,Developmental and Educational Psychology ,Cognitive development ,Humans ,Child ,Social Behavior ,Life-span and Life-course Studies ,Reinforcement ,Psychology ,Cognitive psychology - Published
- 1969
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42. Verbal regulation of behavior and IQ in Canadian Indian and white children
- Author
-
Arthur J. Cropley and Josef Schubert
- Subjects
Cultural background ,Nonverbal communication ,White (horse) ,Intelligence quotient ,Developmental and Educational Psychology ,Cognitive development ,Abstraction ,Life-span and Life-course Studies ,Psychology ,Demography ,Wechsler Intelligence Scale for Children ,Developmental psychology - Published
- 1972
- Full Text
- View/download PDF
43. Mother-infant interactions of teen-age mothers as measured at six months in a natural setting
- Author
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Josef Schubert, Sarah Landy, Chuck Jillings, and Camilla Clark
- Subjects
Adult ,Male ,Adolescent ,Verbal Behavior ,education ,Infant ,Mother-Infant Interactions ,Physical interaction ,Social relation ,Mother-Child Relations ,Education ,Developmental psychology ,Business, Management and Accounting (miscellaneous) ,Humans ,Observational study ,Female ,Interpersonal interaction ,Psychology ,Maternal Behavior ,General Psychology ,Maternal Age - Abstract
Mother-infant interaction of 14 teen-age mothers and their six-month-old infants was observed in the home and compared with that of 12 women 20 years or older and their infants. A further group was designated a “noncontact” group and was seen only at the beginning and end of the first year and was a control for research intervention or experimenter effects. Teen-agers showed few significant differences from older mothers in their mothering skills as measured by simple frequency distributions of individual behaviors and social interaction. Transitional probabilities and flow of interaction matrixes also revealed few significant differences. Like previous studies, the present study found that teen-age mothers showed high warmth and physical interaction but low verbal interaction with their infants. Support of the mothers through experience in the observational sessions may have influenced the results. The possibility is noted of differences in patterns of mothering as the infant develops.
- Published
- 1983
44. The Implications of Luria’s Theories for Cross-cultural Research on Language and Intelligence
- Author
-
Josef Schubert
- Subjects
Cognitive science ,Social condition ,Intellectual development ,Human intelligence ,SIGNAL (programming language) ,Erikson's stages of psychosocial development ,Psychology ,Cross-cultural studies ,On Language ,Social relation - Abstract
The work of A. R. Luria (1960, 1961b, 1963a) on the development of the second signal system combines a biological approach to the study of human behavior with an analysis of the social conditions determining its development. The biological approach is represented by Luria’s research about the stages of development of verbal regulation of behavior. It is complemented by the principle that the content of the second signal system as well as the modes of verbal regulation of behavior are developed through social interaction.
- Published
- 1983
- Full Text
- View/download PDF
45. The stimulus value of the Szondi pictures: a theoretical and empirical study
- Author
-
Josef Schubert
- Subjects
Empirical research ,Szondi test ,General Medicine ,Stimulus (physiology) ,Projective test ,Psychology ,Projective Techniques ,Physiological Phenomenon ,Physiological Phenomena ,Cognitive psychology ,Biological Phenomena - Published
- 1954
46. Effect of training on the performance of the W.I.S.C. 'block design' subtest
- Author
-
Josef Schubert
- Subjects
Intelligence Tests ,Social background ,education ,Humans ,General Medicine ,Psychology ,Child ,Developmental psychology ,Block design ,Education - Abstract
Two groups of normal school children aged 7–8 and 10–11 (N = 91) were trained and retested on the Block Design subtest of the W.I.S.C. Results were not related to sex or age. Significant increase occurred upon retesting, but with large individual differences in reaction to training. Retest scores correlated more highly with intelligence than initial scores. Gain after training correlated positively with intelligence. There were significant differences in reaction to training when the subjects were grouped according to social background. It was found that the initial score of subjects coming from adverse home conditions was a poor measure of their intelligence, whereas in children with favourable social backgrounds, it affords a more valid measure.
- Published
- 1967
47. ERIS, first generation becoming second generation, or re-vitalizing an AO instrument
- Author
-
H. M. Schmid, C. Waring, Adrian M. Glauser, Runa Briguglio, William Taylor, M. Kasper, A. Baruffalo, G. Di Rico, D. Ferruzzi, Mauro Dolci, Matthew A. Kenworthy, David Henry, J. Lightfood, Reinhold J. Dorn, J. Kuehn, Erich Wiezorrek, Alfio Puglisi, Eckhard Sturm, Andreas Glindemann, Mike MacIntosh, Stephen March, A. Cortes, A. Valentino, Rebecca L. Davies, Josef Schubert, Giovanni Cresci, Simone Esposito, Guido Agapito, A. Di Cianno, Christophe Giordano, Bernardo Salasnich, Harald Kuntschner, Helmut Feuchtgruber, C. Rau, A. Buron, Beth Biller, Stefan Gillessen, Sascha P. Quanz, H. Huber, Frans Snik, D. Fatinel, Marco Xompero, N. Förster-Schreiber, David Lunney, F. Mannucci, David Pearson, Markus Plattner, H. Jeroen, Xiaofeng Gao, J. V. Biliotti, Armando Riccardi, Frank Eisenhauer, Christoph U. Keller, Michael Hartl, and Luca Carbonaro
- Subjects
biology ,Computer science ,Systems engineering ,biology.organism_classification ,Eris ,First generation
48. The Performance of Cerebrally Palsied Children on the VRB Test
- Author
-
Ralph Burland and Josef Schubert
- Subjects
medicine.medical_specialty ,medicine ,General Medicine ,Audiology ,Psychology ,Test (assessment) - Published
- 1973
- Full Text
- View/download PDF
49. Reply to J. G. Ingham
- Author
-
Josef Schubert
- Subjects
General Medicine ,Theology ,Psychology - Published
- 1968
- Full Text
- View/download PDF
50. Dating Deuteronomy : The Wellhausen Fallacy
- Author
-
Josef Schubert and Josef Schubert
- Abstract
The Torah was recognized as a unit before the separation between the kingdoms of Judah and Israel. This book challenges established biblical scholarship derived from two assumptions of the Wellhausen Fallacy: a) Deuteronomy could not have been written before the time of Josiah (650 BCE); b) The existence of a group of redactors in the fifth century BCE or later. The first premise is based on the mistranslation of the biblical text. The second is based on the unlikely assumption that the scribes of the Second Temple era felt free to edit old documents or to ascribe their own writings to Mosaic times. The Samarian version of the Pentateuch is virtually identical to the traditional (Masoretic) text. It is preposterous to assume that the Samarians would accept a fictitious Torah composed by Judean exiles of the Persian period or later as authoritative. Neither Samarians nor Judeans copied the Pentateuch from each other. The biblical text and the Samarian texts are merely different editions of the same document.
- Published
- 1901
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