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267 results on '"McFadden, R. A."'

251. LOFAR discovery of a quiet emission mode in PSR B0823+26

Author: F. Breitling, Gottfried Mann, R. Pizzo, John D. Anderson, Cees Bassa, Sera Markoff, Rene P. Breton, Ashish Asgekar, Charlotte Sobey, E. Jütte, George Heald, Heino Falcke, P. Maat, M. J. Norden, M. A. Garrett, Jean-Mathias Grießmeier, Ph. Zarka, Rebecca McFadden, H. Paas, Ben Stappers, E. de Geus, Sarod Yatawatta, V. I. Kondratiev, D. D. Mulcahy, J. van Leeuwen, S. ter Veen, M. Pilia, M. Pandey-Pommier, Ralph A. M. J. Wijers, A. W. Gunst, J. Sluman, Olaf Wucknitz, H. J. A. Röttgering, Philip Best, Christian Vocks, D. McKay-Bukowski, Michel Tagger, D. Carbone, A. Alexov, Andrew Lyne, Antonia Rowlinson, A. Noutsos, Adam Stewart, Chiara Ferrari, T. E. Hassall, Evan Keane, Patrick Weltevrede, Jason W. T. Hessels, Satyendra Thoudam, S. Duscha, M. Serylak, A. van Duin, G. Pietka, Laura Birzan, Jochen Eislöffel, J. P. Hamaker, Wilfred Frieswijk, C. Toribio, Michael Kramer, D. A. Rafferty, A. G. Polatidis, Arthur Corstanje, A. Nelles, John D. Swinbank, Y. Tang, Anna M. M. Scaife, Martin Bell, N. J. Young, V. N. Pandey, Gerard H. Kuper, Cyril Tasse, J. W. Broderick, H. Munk, John McKean, Marcus Brüggen, Matthias Steinmetz, Annalisa Bonafede, A. Renting, Richard Fallows, R. Vermeulen, Mark J. Bentum, Matthias Hoeft, M. de Vos, Aris Karastergiou, Michael W. Wise, Gianni Bernardi, Jörg R. Hörandel, Rob Fender, Oleg Smirnov, Emanuela Orru, Dominik J. Schwarz, I. M. Avruch, Anna V. Bilous, R. J. van Weeren, Sobey, C., Young, N.J., Hessels, J.W.T., Weltevrede, P., Noutsos, A., Stappers, B.W., Kramer, M., Bassa, C., Lyne, A.G., Kondratiev V.I., null, Hassall, T.E., Keane, E.F., Bilous, A.V., Breton, R.P., Grießmeier, J.M., Karastergiou, A., Pilia, M., Serylak, M., Ter Veen, S., Van Leeuwen, J., Alexov, A., Anderson, J., Asgekar, A., Avruch, I.M., Bell, M.E., Bentum, M.J., Bernardi, G., Best, P., Bĭrzan, L., Bonafede, A., Breitling, F., Broderick, J., Brüggen, M., Corstanje, A., Carbone, D., De Geus, E., De Vos, M., Van Duin, A., Duscha, S., Eislöffel, J., Falcke, H., Fallows, R.A., Fender, R., Ferrari, C., Frieswijk, W., Garrett, M.A., Gunst, A.W., Hamaker, J.P., Heald, G., Hoeft, M., Hörandel, J., Jütte, E., Kuper, G., Maat, P., Mann, G., Markoff, S., McFadden, R., McKay-Bukowski, D., McKean, J.P., Mulcahy, D.D., Munk, H., Nelles, A., Norden, M.J., Orrù, E., Paas, H., Pandey-Pommier, M., Pandey, V.N., Pietka, G., Pizzo, R., Polatidis, A.G., Rafferty, D., Renting, A., Röttgering, H., Rowlinson, A., Scaife, A.M.M., Schwarz, D., Sluman, J., Smirnov, O., Steinmetz, M., Stewart, A., Swinbank, J., Tagger, M., Tang, Y., Tasse, C., Thoudam, S., Toribio, C., Vermeulen, R., Vocks, C., Van Weeren, R.J., Wijers, R.A.M.J., Wise, M.W., Wucknitz, O., Yatawatta, S., Zarka, P., Max-Planck-Institut für Radioastronomie (MPIFR), University of Minnesota [Twin Cities] (UMN), University of Minnesota System, University of Amsterdam [Amsterdam] (UvA), Jodrell Bank Centre for Astrophysics, University of Manchester [Manchester], Columbia Astrophysics Laboratory (CAL), Columbia University [New York], Cornell University [New York], Netherlands Institute for Radio Astronomy (ASTRON), Centre for Astrophysics and Supercomputing [Swinburne] (CAS), Swinburne University of Technology [Melbourne], Institute for Mathematics, Astrophysics and Particle Physics (IMAPP), Radboud University [Nijmegen], Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Unité Scientifique de la Station de Nançay (USN), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Rhodes University, Grahamstown, Oxford Astrophysics, University of Oxford, Institute for Mathematics Applied to Geoscience, National Center for Atmospheric Research [Boulder] (NCAR), SRON Netherlands Institute for Space Research (SRON), CSIRO Astronomy and Space Science, Commonwealth Scientific and Industrial Research Organisation [Canberra] (CSIRO), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), University of Edinburgh, Leiden Observatory [Leiden], Universiteit Leiden, Jacobs University [Bremen], Leibniz-Institut für Astrophysik Potsdam (AIP), University of Southampton, Medstar Research Institute, Thüringer Landessternwarte Tautenburg (TLS), Institute of Mathematical and Physical Sciences, Département de Géologie, Université de Montréal (UdeM), University Bochum, Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Oulu, Center for Information Technology CIT, Université de Groningen, Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), National Radio Astronomy Observatory [Charlottesville] (NRAO), National Radio Astronomy Observatory (NRAO), Department of Astronomy and Astrophysics [PennState], Pennsylvania State University (Penn State), Penn State System-Penn State System, School of Physics and Astronomy [Southampton], Interactions Son Musique Mouvement, Sciences et Technologies de la Musique et du Son (STMS), Institut de Recherche et Coordination Acoustique/Musique (IRCAM)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche et Coordination Acoustique/Musique (IRCAM)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Leibniz-Institut DSMZ-Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH / Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Cultures (DSMZ), Laboratory for Atmospheric and Space Physics [Boulder] (LASP), University of Colorado [Boulder], Université Paris-Sud - Paris 11 (UP11), 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), SKA South Africa, Ska South Africa, Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University-Smithsonian Institution, Argelander-Institut für Astronomie (AlfA), Rheinische Friedrich-Wilhelms-Universität Bonn, We would like to thank R. Karuppusamy for his help with the Effelsberg observations. CF acknowledges financial support by the Agence Nationale de la Recherche through grant ANR-09-JCJC-0001-01., European Project: 337062,EC:FP7:ERC,ERC-2013-StG,DRAGNET(2014), ITA, GBR, FRA, DEU, NLD, Radboud university [Nijmegen], Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National d’Études Spatiales [Paris] (CNES), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO), University of Oxford [Oxford], Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Pierre et Marie Curie - Paris 6 (UPMC), Universiteit Leiden [Leiden], École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Harvard University [Cambridge]-Smithsonian Institution, Astronomy, and High Energy Astrophys. & Astropart. Phys (API, FNWI)
Subjects: stars, PSR B0823+26-radio telescopes, Astronomy, Astrophysics::High Energy Astrophysical Phenomena, Pulsar planet, FOS: Physical sciences, neutron- pulsars, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, neutron [stars], Pulsar, Millisecond pulsar, Pulsars: individual: PSR B0823+26, individual, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics::Galaxy Astrophysics, Astroparticle physics, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy and Astrophysics, LOFAR, Astronomy and Astrophysic, Stars: neutron, Stars, Neutron star, Astrophysics - Solar and Stellar Astrophysics, magnetosphere-pulsars, [SDU]Sciences of the Universe [physics], Space and Planetary Science, QUIET, ComputingMethodologies_DOCUMENTANDTEXTPROCESSING, Astrophysics - High Energy Astrophysical Phenomena, individual: PSR B0823+26 [pulsars]
Abstract: PSR B0823+26, a 0.53-s radio pulsar, displays a host of emission phenomena over timescales of seconds to (at least) hours, including nulling, subpulse drifting, and mode-changing. Studying pulsars like PSR B0823+26 provides further insight into the relationship between these various emission phenomena and what they might teach us about pulsar magnetospheres. Here we report on the LOFAR discovery that PSR B0823+26 has a weak and sporadically emitting 'quiet' (Q) emission mode that is over 100 times weaker (on average) and has a nulling fraction forty-times greater than that of the more regularly-emitting 'bright' (B) mode. Previously, the pulsar has been undetected in the Q-mode, and was assumed to be nulling continuously. PSR B0823+26 shows a further decrease in average flux just before the transition into the B-mode, and perhaps truly turns off completely at these times. Furthermore, simultaneous observations taken with the LOFAR, Westerbork, Lovell, and Effelsberg telescopes between 110 MHz and 2.7 GHz demonstrate that the transition between the Q-mode and B-mode occurs within one single rotation of the neutron star, and that it is concurrent across the range of frequencies observed., Comment: 15 pages, 8 figures, 2 tables, accepted for publication in MNRAS
Published: 2015
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252. LOFAR imaging of Cygnus A - direct detection of a turnover in the hotspot radio spectra

Author: Aris Karastergiou, Michael W. Wise, Gianni Bernardi, Heino Falcke, L. Cerrigone, D. Engels, Michel Tagger, Simona Vegetti, Anna Nelles, R. Morganti, John D. Swinbank, Leith Godfrey, George Heald, I. van Bemmel, E. Juette, P. Maat, Sera Markoff, V. I. Kondratiev, Léon V. E. Koopmans, Huib Intema, Adam Deller, H. Munk, J. W. Broderick, Marcus Brüggen, R. Blaauw, J. Sluman, M. Iacobelli, R. J. van Weeren, Roberto Pizzo, Philip Best, A. J. van der Horst, D. McKay-Bukowski, Wilfred Frieswijk, M. Pandey-Pommier, Martin J. Hardcastle, M. Pietka, Aleksandar Shulevski, Rainer Beck, Satyendra Thoudam, M. Serylak, Matthias Steinmetz, Anna M. M. Scaife, Emanuela Orrú, Antonia Rowlinson, D. D. Mulcahy, Sarod Yatawatta, H. Paas, Adam Stewart, S. Duscha, I. M. Avruch, Frank Breitling, B. Ciardi, John McKean, H. J. A. Röttgering, R. C. Vermeulen, Oleg Smirnov, Olaf Wucknitz, W. Reich, Gottfried Mann, F. de Gasperin, P. Zarka, M. Kuniyoshi, D. Rafferty, Martin Bell, Richard Fallows, James M. Anderson, G. Kuper, Mark J. Bentum, M. A. Garrett, J.-M. Grießmeier, Matthias Hoeft, Christian Vocks, M. P. van Haarlem, M. C. Toribio, A. G. Polatidis, J. van Leeuwen, Annalisa Bonafede, Rebecca McFadden, Netherlands Institute for Radio Astronomy (ASTRON), SRON Netherlands Institute for Space Research (SRON), Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), University of Hertfordshire [Hatfield] (UH), Department of Astronomy and Astrophysics [PennState], Pennsylvania State University (Penn State), Penn State System-Penn State System, Department of Atmospheric and Planetary Sciences [Hampton] (APS), Hampton University, Kapteyn Astronomical Institute [Groningen], University of Groningen [Groningen], Université de Tours (UT), CSIRO Astronomy and Space Science, Commonwealth Scientific and Industrial Research Organisation [Canberra] (CSIRO), University of Southampton, Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), University of Edinburgh, Jacobs University [Bremen], Leibniz-Institut für Astrophysik Potsdam (AIP), Max Planck Institute for Astrophysics, Max-Planck-Gesellschaft, Hamburger Sternwarte/Hamburg Observatory, Universität Hamburg (UHH), Institute for Mathematics, Astrophysics and Particle Physics (IMAPP), Radboud University [Nijmegen], Institute of Mathematical and Physical Sciences, Leiden Observatory [Leiden], Universiteit Leiden, Unité Scientifique de la Station de Nançay (USN), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Joint Institute for VLBI in Europe (JIVE ERIC), Department of Pure Mathematics and Mathematical Statistics (DPMMS), Faculty of mathematics Centre for Mathematical Sciences [Cambridge] (CMS), University of Cambridge [UK] (CAM)-University of Cambridge [UK] (CAM), Ruhr-Universität Bochum [Bochum], Oxford Astrophysics, University of Oxford, Max-Planck-Institut für Radioastronomie (MPIFR), University of Oulu, University of Groningen, Groningen, Netherlands, Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Australia Telescope National Facility (ATNF), School of Physics and Astronomy [Southampton], Department of Physics and Astronomy [South Africa], University of the Western Cape (UWC), Rhodes University, Grahamstown, Leibniz-Institut DSMZ-Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH / Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Cultures (DSMZ), Laboratory for Atmospheric and Space Physics [Boulder] (LASP), University of Colorado [Boulder], Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University-Smithsonian Institution, Argelander-Institut für Astronomie (AlfA), Rheinische Friedrich-Wilhelms-Universität Bonn, 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), European Project: 320745,EC:FP7:ERC,ERC-2012-ADG_20120216,RADIOLIFE(2013), Astronomy, McKean, J.P., Godfrey, L.E.H., Vegetti, S., Wise, M.W., Morganti, R., Hardcastle, M.J., Rafferty, D., Anderson, J., Avruch, I.M., Beck, R., Bell, M.E., van Bemmel, I., Bentum, M.J., Bernardi, G., Best, P., Blaauw, R., Bonafede, A., Breitling, F., Broderick, J.W., Brüggen, M., Cerrigone, L., Ciardi, B., de Gasperin, F., Deller, A., Duscha, S., Engels, D., Falcke, H., Fallows, R.A., Frieswijk, W., Garrett, M.A., Grießmeier, J.M., van Haarlem, M.P., Heald, G., Hoeft, M., van der HorstA.J., null, Iacobelli, M., Interna, H., Juette, E., Karastergiou, A., Kondratiev, V.I., Koopmans, L.V.E., Kuniyoshi, M., Kuper, G., van Leeuwen, J., Maat, P., Mann, G., Markoff, S., McFadden, R., McKay-Bukowski, D., Mulcahy, D.D., Munk, H., Nelles, A., Orru, E., Paas, H., Pandey-Pommier, M., Pietka, M., Pizzo, R., Polatidis, A.G., Reich, W., Rottgering, H.J.A., Rowlinson, A., Scaife, A.M.M., Serylak, M., Shulevski, A., Sluman, J., Smirnov, O., Steinmetz, M., Stewart, A., Swinbank, J., Tagger, M., Thoudam, S., Toribio, M.C., Vermeulen, R., Vocks, C., van Weeren, R.J., Wucknitz, O., Yatawatta, S., Zarka, P., High Energy Astrophys. & Astropart. Phys (API, FNWI), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Pierre et Marie Curie - Paris 6 (UPMC), Radboud university [Nijmegen], Universiteit Leiden [Leiden], Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), University of Oxford [Oxford], École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), University of the Western Cape, Smithsonian Institution-Harvard University [Cambridge], ITA, GBR, FRA, DEU, NLD, Université de Tours, Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université d'Orléans (UO), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National d’Études Spatiales [Paris] (CNES), and Harvard University [Cambridge]-Smithsonian Institution
Subjects: Radio galaxy, Astronomy, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Radio continuum: galaxie, Spectral line, Radio spectrum, Radio continuum: galaxies, Galaxies: active: individual: Cygnus A, X-shaped radio galaxy, 0103 physical sciences, Cygnus A, 010303 astronomy & astrophysics, Physics, Spectral index, EWI-27659, 010308 nuclear & particles physics, LOBES, Astronomy and Astrophysics, LOFAR, Astronomy and Astrophysic, Astrophysics - Astrophysics of Galaxies, Galaxy, galaxies [radio continuum], GALAXIES, METIS-321690, RESOLUTION, Space and Planetary Science, HOT-SPOTS, GAS, [SDU]Sciences of the Universe [physics], Astrophysics of Galaxies (astro-ph.GA), ComputingMethodologies_DOCUMENTANDTEXTPROCESSING, ARRAY, IR-103274
Abstract: The low-frequency radio spectra of the hotspots within powerful radio galaxies can provide valuable information about the physical processes operating at the site of the jet termination. These processes are responsible for the dissipation of jet kinetic energy, particle acceleration, and magnetic-field generation. Here we report new observations of the powerful radio galaxy Cygnus A using the Low Frequency Array (LOFAR) between 109 and 183 MHz, at an angular resolution of ~3.5 arcsec. The radio emission of the lobes is found to have a complex spectral index distribution, with a spectral steepening found towards the centre of the source. For the first time, a turnover in the radio spectrum of the two main hotspots of Cygnus A has been directly observed. By combining our LOFAR imaging with data from the Very Large Array at higher frequencies, we show that the very rapid turnover in the hotspot spectra cannot be explained by a low-energy cut-off in the electron energy distribution, as has been previously suggested. Thermal (free-free) absorption or synchrotron self absorption models are able to describe the low-frequency spectral shape of the hotspots, however, as with previous studies, we find that the implied model parameters are unlikely, and interpreting the spectra of the hotspots remains problematic., Comment: 9 pages, 3 figures, accepted for publication in MNRAS
Published: 2016
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253. Wide-band, low-frequency pulse profiles of 100 radio pulsars with LOFAR

Author: J. van Leeuwen, Matthias Steinmetz, T. E. Hassall, A. Nelles, E. de Geus, M. Pilia, B. W. Stappers, Heino Falcke, H. J. A. Röttgering, Annalisa Bonafede, Oleg Smirnov, Anna V. Bilous, Satyendra Thoudam, Evan Keane, Peter G. Jonker, W. Frieswijk, Rudy Wijnands, A. Noutsos, M. Pietka, John D. Swinbank, Richard Fallows, R. J. van Weeren, M. Pandey-Pommier, Olaf Wucknitz, A. Alexov, Rebecca McFadden, E. Juette, F. Breitling, Stefan J. Wijnholds, Aris Karastergiou, Benedetta Ciardi, H. Paas, Antonia Rowlinson, Dominik J. Schwarz, Michael Kramer, A. I. F. Stewart, Y. Tang, Ashish Asgekar, K. Zagkouris, James A. Anderson, Chiara Ferrari, S. Duscha, James Miller-Jones, Andrew Lyne, Stefan Oslowski, Adam T. Deller, A. de Jong, R. C. Vermeulen, Gianni Bernardi, I. M. Avruch, M. A. Garrett, M. C. Toribio, Jochen Eislöffel, Charlotte Sobey, A. J. van der Horst, Rene P. Breton, Cyril Tasse, Marcus Brüggen, J. W. Broderick, Gerard H. Kuper, S. ter Veen, A. W. Gunst, Rob Fender, P. Zarka, D. McKay-Bukowski, Martin Bell, A. Horneffer, M. Kuniyoshi, Patrick Weltevrede, M. Serylak, A. G. Polatidis, Ralph A. M. J. Wijers, Mark J. Bentum, Christian Vocks, Jean-Mathias Grießmeier, Sera Markoff, Jason W. T. Hessels, Stephane Corbel, Laura Birzan, J. P. Hamaker, Wolfgang Reich, Michel Tagger, P. Maat, V. I. Kondratiev, George Heald, Gottfried Mann, R. Pizzo, Astronomy, Netherlands Institute for Radio Astronomy (ASTRON), Jodrell Bank Centre for Astrophysics, University of Manchester [Manchester], Vrije Universiteit Medical Centre (VUMC), Vrije Universiteit Amsterdam [Amsterdam] (VU), Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), Oxford Astrophysics, University of Oxford, School of Physics and Astronomy [Southampton], University of Southampton, Institute for Mathematics, Astrophysics and Particle Physics (IMAPP), Radboud University [Nijmegen], Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Unité Scientifique de la Station de Nançay (USN), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Centre for Astrophysics and Supercomputing [Swinburne] (CAS), Swinburne University of Technology [Melbourne], Department of Physics [Oxford], Max-Planck-Institut für Radioastronomie (MPIFR), Universität Bielefeld = Bielefeld University, University of Cape Town, Space Telescope Science Institute (STSci), Epidémiologie et Biostatistique [Bordeaux], Université Bordeaux Segalen - Bordeaux 2-Institut de Santé Publique, d'Épidémiologie et de Développement (ISPED)-Institut National de la Santé et de la Recherche Médicale (INSERM), SRON Netherlands Institute for Space Research (SRON), Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University [Cambridge]-Smithsonian Institution, Leiden Observatory [Leiden], Universiteit Leiden [Leiden], University of Hamburg, Leibniz-Institut DSMZ-Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH / Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Cultures (DSMZ), University of Edinburgh, Max-Planck-Institut für Astrophysik (MPA), Max-Planck-Gesellschaft, Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Structural Dynamics and Acoustics, University of Twente, Thüringer Landessternwarte Tautenburg (TLS), Institute of Mathematical and Physical Sciences, Department of Astrophysics [Oxford], Département de Géologie, Université de Montréal (UdeM), Astronomisches Institut der Ruhr-Universität Bochum, Ruhr-Universität Bochum [Bochum], Leibniz-Institut für Astrophysik Potsdam (AIP), Department of Physical Sciences, University of Oulu, University of Oulu, Curtin University [Perth], Planning and Transport Research Centre (PATREC), University of Groningen [Groningen], Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Australia Telescope National Facility (ATNF), Commonwealth Scientific and Industrial Research Organisation [Canberra] (CSIRO), Institute of Farm Animal Genetics (ING), Friedrich-Loeffler-Institut (FLI), SKA South Africa, Ska South Africa, Astrophysikalisches Institut Potsdam (AIP), Department of Physics [Dunedin], University of Otago [Dunedin, Nouvelle-Zélande], Princeton University, Edinburgh Research Station, Centre for Ecology and Hydrology, 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), Department of Astrophysics [Nijmegen], Radboud University [Nijmegen]-Radboud University [Nijmegen], Anton Pannekoek Institute for Astronomy, Argelander-Institut für Astronomie (AlfA), Rheinische Friedrich-Wilhelms-Universität Bonn, Alexander von Humboldt Foundation Agence Nationale de la Recherche ANR-09-JCJC-0001-01, ANR-09-JCJC-0001,OPALES(2009), European Project: 337062,EC:FP7:ERC,ERC-2013-StG,DRAGNET(2014), European Project: 617199,EC:FP7:ERC,ERC-2013-CoG,ALERT(2014), European Project: 224838,EC:FP7:PEOPLE,FP7-PEOPLE-2007-4-3-IRG,PULSARS WITH LOFAR(2008), ROUCHON, Nathalie, Jeunes chercheuses et jeunes chercheurs - - OPALES2009 - ANR-09-JCJC-0001 - JCJC - VALID, DRAGNET: A high-speed, wide-angle camera for catching extreme astrophysical events - DRAGNET - - EC:FP7:ERC2014-01-01 - 2018-12-31 - 337062 - VALID, ALERT - The Apertif-LOFAR Exploration of the Radio Transient Sky - ALERT - - EC:FP7:ERC2014-12-01 - 2019-11-30 - 617199 - VALID, Radio pulsars with LOFAR: a study of extreme physics laboratories. - PULSARS WITH LOFAR - - EC:FP7:PEOPLE2008-05-01 - 2012-04-30 - 224838 - VALID, High Energy Astrophys. & Astropart. Phys (API, FNWI), University of Oxford [Oxford], Radboud university [Nijmegen], Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), Fakultät für Physik, Universität Bielefeld, Universität Bielefeld, University of the Western Cape, Cape Town, Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), University of Twente [Netherlands], Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Radboud university [Nijmegen]-Radboud university [Nijmegen], Harvard University-Smithsonian Institution, Universiteit Leiden, École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Pilia, M., Hessels, J.W.T., Stappers, B.W., Kondratiev, V.I., Kramer, M., Van Leeuwen, J., Weltevrede, P., Lyne, A.G., Zagkouris, K., Hassall, T.E., Bilous, A.V., Breton, R.P., Falcke, H., Grießmeier, J.-M., Keane, E., Karastergiou, A., Kuniyoshi, M., Noutsos, A., Osłowski, S., Serylak, M., Sobey, C., Ter Veen, S., Alexov, A., Anderson, J., Asgekar, A., Avruch, I.M., Bell, M.E., Bentum, M.J., Bernardi, G., Bîrzan, L., Bonafede, A., Breitling, F., Broderick, J.W., Brüggen, M., Ciardi, B., Corbel, S., De Geus, E., De Jong, A., Deller, A., Duscha, S., Eislöffel, J., Fallows, R.A., Fender, R., Ferrari, C., Frieswijk, W., Garrett, M.A., Gunst, A.W., Hamaker, J.P., Heald, G., Horneffer, A., Jonker, P., Juette, E., Kuper, G., Maat, P., Mann, G., Markoff, S., McFadden, R., McKay-Bukowski, D., Miller-Jones, J.C.A., Nelles, A., Paas, H., Pandey-Pommier, M., Pietka, M., Pizzo, R., Polatidis, A.G., Reich, W., Röttgering, H., Rowlinson, A., Schwarz, D., Smirnov, O., Steinmetz, M., Stewart, A., Swinbank, J.D., Tagger, M., Tang, Y., Tasse, C., Thoudam, S., Toribio, M.C., Van Der Horst, A.J., Vermeulen, R., Vocks, C., Van Weeren, R.J., Wijers, R.A.M.J., Wijnands, R., Wijnholds, S.J., Wucknitz, O., and Zarka, P.
Subjects: Astronomy, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics, METIS-321663, Astrophysics::Cosmology and Extragalactic Astrophysics, Low frequency, 01 natural sciences, Radio spectrum, law.invention, Telescope, Radio telescope, [SDU] Sciences of the Universe [physics], stars: neutron, Pulsar, law, pulsars: general, 0103 physical sciences, 010303 astronomy & astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM), IR-103184, Solar and Stellar Astrophysics (astro-ph.SR), Physics, High Energy Astrophysical Phenomena (astro-ph.HE), 010308 nuclear & particles physics, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy and Astrophysics, LOFAR, Astronomy and Astrophysic, Astrophysics - Astrophysics of Galaxies, Interstellar medium, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, [SDU]Sciences of the Universe [physics], Astrophysics of Galaxies (astro-ph.GA), ComputingMethodologies_DOCUMENTANDTEXTPROCESSING, Radio frequency, EWI-27451, Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Instrumentation and Methods for Astrophysics
Abstract: LOFAR offers the unique capability of observing pulsars across the 10-240 MHz frequency range with a fractional bandwidth of roughly 50%. This spectral range is well-suited for studying the frequency evolution of pulse profile morphology caused by both intrinsic and extrinsic effects: such as changing emission altitude in the pulsar magnetosphere or scatter broadening by the interstellar medium, respectively. The magnitude of most of these effects increases rapidly towards low frequencies. LOFAR can thus address a number of open questions about the nature of radio pulsar emission and its propagation through the interstellar medium. We present the average pulse profiles of 100 pulsars observed in the two LOFAR frequency bands: High Band (120-167 MHz, 100 profiles) and Low Band (15-62 MHz, 26 profiles). We compare them with Westerbork Synthesis Radio Telescope (WSRT) and Lovell Telescope observations at higher frequencies (350 and1400 MHz) in order to study the profile evolution. The profiles are aligned in absolute phase by folding with a new set of timing solutions from the Lovell Telescope, which we present along with precise dispersion measures obtained with LOFAR. We find that the profile evolution with decreasing radio frequency does not follow a specific trend but, depending on the geometry of the pulsar, new components can enter into, or be hidden from, view. Nonetheless, in general our observations confirm the widening of pulsar profiles at low frequencies, as expected from radius-to-frequency mapping or birefringence theories. We offer this catalog of low-frequency pulsar profiles in a user friendly way via the EPN Database of Pulsar Profiles (http://www.epta.eu.org/epndb/)., Comment: 38 pages, 11 figures, 5 tables, A&A in press, updated with editorial corrections
Published: 2016
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254. LBCS: The LOFAR Long-Baseline Calibrator Survey

Author: Rebecca McFadden, G. M. Loose, J. van Leeuwen, J. Schaap, N. J. Vermaas, M. P. van Haarlem, Philip Best, M. Sipior, E. de Geus, E. Juette, D. Engels, Sarod Yatawatta, J. Moldón, George Heald, Anna M. M. Scaife, C. Vocks, F. Breitling, M. Iacobelli, L. Cerrigone, D. D. Mulcahy, H. J. A. Röttgering, Matthias Hoeft, John D. Swinbank, Jean-Mathias Griessmeier, W. Reich, P. Maat, James M. Anderson, M. A. Garrett, Amitpal S. Tagore, I. van Bemmel, J. Sluman, Roberto Pizzo, R. Vermeulen, Marcus Brüggen, Satyendra Thoudam, Aleksandar Shulevski, R. Blaauw, M. C. Toribio, Emanuela Orrú, A. Horneffer, R. J. van Weeren, W. N. Brouw, Martin Bell, M. Avruch, Michael W. Wise, Jörg R. Hörandel, D. McKay-Bukowski, Jochen Eislöffel, Gerard H. Kuper, P. Zarka, Adam Deller, A. Drabent, Mark J. Bentum, Arthur Corstanje, Dominik J. Schwarz, Matthias Steinmetz, F. de Gasperin, Richard Fallows, H. Munk, A. G. Polatidis, Tobia Carozzi, Annalisa Bonafede, S. ter Veen, Leah K. Morabito, A. W. Gunst, John Conway, Anna D. Kapińska, Huib Intema, Heino Falcke, J. W. Broderick, M. Pandey-Pommier, Neal Jackson, Antonia Rowlinson, John McKean, Michiel A. Brentjens, B. Ciardi, Eskil Varenius, O. Wucknitz, M. Kuniyoshi, School of Physics and Astronomy [Manchester], University of Manchester [Manchester], Netherlands Institute for Radio Astronomy (ASTRON), Departament d'Astronomia i Meteorologia [Barcelona], Universitat de Barcelona (UB), Onsala Space Observatory, Dept. of Radio and Space Science, Chalmers University of Technology, Chalmers University of Technology [Göteborg], ARC Centre of Excellence for Autonomous Systems (CAS), University of Technology Sydney (UTS), Swedish Institute of Space Physics [Uppsala] (IRF), Department of Pure Mathematics and Mathematical Statistics (DPMMS), Faculty of mathematics Centre for Mathematical Sciences [Cambridge] (CMS), University of Cambridge [UK] (CAM)-University of Cambridge [UK] (CAM), Department of Astrophysics [Nijmegen], Institute for Mathematics, Astrophysics and Particle Physics (IMAPP), Radboud university [Nijmegen]-Radboud university [Nijmegen], GeoForschungsZentrum - Helmholtz-Zentrum Potsdam (GFZ), Newcastle University [Newcastle], Joint Institute for VLBI in Europe (JIVE ERIC), University of Hamburg, Leiden Observatory [Leiden], Universiteit Leiden [Leiden], Leibniz-Institut für Astrophysik Potsdam (AIP), Oxford Astrophysics, University of Oxford [Oxford], University of Southampton, Kapteyn Astronomical Institute [Groningen], University of Groningen [Groningen], University of Edinburgh, Radboud university [Nijmegen], Thüringer Landessternwarte Tautenburg (TLS), Hamburger Sternwarte/Hamburg Observatory, Universität Hamburg (UHH), Unité Scientifique de la Station de Nançay (USN), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Max-Planck-Institut für Radioastronomie (MPIFR), Astronomisches Institut der Ruhr-Universität Bochum, Ruhr-Universität Bochum [Bochum], National Astronomical Observatory of Japan (NAOJ), Health Service Executive [Dublin] (HSE), Aalborg University [Denmark] (AAU), Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Astrophysikalisches Institut Potsdam (AIP), Princeton University, SRON Netherlands Institute for Space Research (SRON), 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), European Project: 283393,EC:FP7:INFRA,FP7-INFRASTRUCTURES-2011-1,RADIONET3(2012), High Energy Astrophys. & Astropart. Phys (API, FNWI), Radboud University [Nijmegen]-Radboud University [Nijmegen], Universiteit Leiden, University of Oxford, Radboud University [Nijmegen], Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Jackson, N., Tagore, A., Deller, A., Moldón, J., Varenius, E., Morabito, L., Wucknitz, O., Carozzi, T., Conway, J., Drabent, A., Kapinska, A., Orrù, E., Brentjens, M., Blaauw, R., Kuper, G., Sluman, J., Schaap, J., Vermaas, N., Iacobelli, M., Cerrigone, L., Shulevski, A., Ter Veen, S., Fallows, R., Pizzo, R., Sipior, M., Anderson, J., Avruch, I.M., Bell, M.E., Van Bemmel, I., Bentum, M.J., Best, P., Bonafede, A., Breitling, F., Broderick, J.W., Brouw, W.N., Brüggen, M., Ciardi, B., Corstanje, A., De Gasperin, F., De Geus, E., Eislöffel, J., Engels, D., Falcke, H., Garrett, M.A., Grießmeier, J.M., Gunst, A.W., Van Haarlem, M.P., Heald, G., Hoeft, M., Hörandel, J., Horneffer, A., Intema, H., Juette, E., Kuniyoshi, M., Van Leeuwen, J., Loose, G.M., Maat, P., McFadden, R., McKay-Bukowski, D., McKean, J.P., Mulcahy, D.D., Munk, H., Pandey-Pommier, M., Polatidis, A.G., Reich, W., Röttgering, H.J.A., Rowlinson, A., Scaife, A.M.M., Schwarz, D.J., Steinmetz, M., Swinbank, J., Thoudam, S., Toribio, M.C., Vermeulen, R., Vocks, C., Van Weeren, R.J., Wise, M.W., Yatawatta, S., Zarka, P., and Astronomy
Subjects: Coherence time, media_common.quotation_subject, Astronomy, interferometers [instrumentation], galaxies: active, EWI-27445, Flux, FOS: Physical sciences, 02 engineering and technology, 01 natural sciences, Radio continuum: galaxie, law.invention, Instrumentation: interferometer, Telescope, surveys, law, 0103 physical sciences, 0202 electrical engineering, electronic engineering, information engineering, Range (statistics), Astronomy, Astrophysics and Cosmology, Survey, instrumentation: interferometers, 010303 astronomy & astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM), GeneralLiterature_REFERENCE(e.g.,dictionaries,encyclopedias,glossaries), media_common, radio continuum: galaxies, Instrumentation:interferometers- Techniques:interferometric - Surveys - Galaxies:active -Radio continuum:galaxies, 020206 networking & telecommunications, Astronomy and Astrophysics, LOFAR, Astronomy and Astrophysic, Geodesy, Astrophysics - Astrophysics of Galaxies, galaxies [radio continuum], Square degree, interferometric [techniques], METIS-319490, Sky, Space and Planetary Science, techniques: interferometric, [SDU]Sciences of the Universe [physics], Astrophysics of Galaxies (astro-ph.GA), active [galaxies], Environmental science, Astrophysics - Instrumentation and Methods for Astrophysics, IR-102283, Coherence (physics)
Abstract: (abridged). We outline LBCS (the LOFAR Long-Baseline Calibrator Survey), whose aim is to identify sources suitable for calibrating the highest-resolution observations made with the International LOFAR Telescope, which include baselines >1000 km. Suitable sources must contain significant correlated flux density (50-100mJy) at frequencies around 110--190~MHz on scales of a few hundred mas. At least for the 200--300-km international baselines, we find around 1 suitable calibrator source per square degree over a large part of the northern sky, in agreement with previous work. This should allow a randomly selected target to be successfully phase calibrated on the international baselines in over 50% of cases. Products of the survey include calibrator source lists and fringe-rate and delay maps of wide areas -- typically a few degrees -- around each source. The density of sources with significant correlated flux declines noticeably with baseline length over the range 200--600~km, with good calibrators on the longest baselines appearing only at the rate of 0.5 per square degree. Coherence times decrease from 1--3 minutes on 200-km baselines to about 1 minute on 600-km baselines, suggesting that ionospheric phase variations contain components with scales of a few hundred kilometres. The longest median coherence time, at just over 3 minutes, is seen on the DE609 baseline, which at 227km is close to being the shortest. We see median coherence times of between 80 and 110 seconds on the four longest baselines (580--600~km), and about 2 minutes for the other baselines. The success of phase transfer from calibrator to target is shown to be influenced by distance, in a manner that suggests a coherence patch at 150-MHz of the order of 1 degree., Accepted by Astronomy & Astrophysics. Error in figure 6 corrected
Published: 2016
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255. LOFAR MSSS: detection of a low-frequency radio transient in 400 h of monitoring of the North Celestial Pole

Author: Rebecca McFadden, Martin Bell, Sera Markoff, G. Kokotanekov, R. J. van Weeren, D. McKay-Bukowski, James M. Anderson, Jason W. T. Hessels, Peter G. Jonker, Ralph A. M. J. Wijers, H. Munk, Casey J. Law, Frank Breitling, B. Scheers, Marcus Brüggen, M. C. Toribio, A. Horneffer, George Heald, M. A. Garrett, Aris Karastergiou, Luke Pratley, Rudy Wijnands, Y. Cendes, F. de Gasperin, A. Alexov, Michael W. Wise, Gianni Bernardi, Jörg R. Hörandel, B. Ciardi, M. Kuniyoshi, James Miller-Jones, J. van Leeuwen, T. Munoz-Darias, Aleksandar Shulevski, John McKean, J.-M. Grießmeier, John D. Swinbank, Jochen Eislöffel, P. Maat, Cyril Tasse, Wilfred Frieswijk, M. J. Norden, J. W. Broderick, A. G. Polatidis, Arthur Corstanje, T E Hassall, Heino Falcke, Harvey Butcher, E. de Geus, V. I. Kondratiev, E. Juette, Anna M. M. Scaife, M. Pandey-Pommier, Benjamin Stappers, H. Paas, A. W. Gunst, I. M. Avruch, Volker Heesen, D. Carbone, Mark J. Bentum, Antonia Rowlinson, Annalisa Bonafede, Rob Fender, J. Sluman, E. Rol, Matthias Steinmetz, Chiara Ferrari, Gijs Molenaar, S. Duscha, G. Kuper, D. D. Mulcahy, Sarod Yatawatta, Philip Best, M. Pietka, H. J. A. Röttgering, Satyendra Thoudam, A. O. Clarke, Adam Stewart, M. P. van Haarlem, Charlotte Sobey, M. Iacobelli, Olaf Wucknitz, Matthias Hoeft, Emanuela Orrú, M. Loose, Ph. Zarka, Adam Deller, Martin J. Hardcastle, Tim D. Staley, Ashish Asgekar, J. Moldon, Dominik J. Schwarz, A. J. van der Horst, Christian Vocks, Rene P. Breton, John Conway, Stephane Corbel, R. C. Vermeulen, Stefan J. Wijnholds, S. van Velzen, T. L. Grobler, Oleg Smirnov, Astronomy, Laboratory for Atmospheric and Space Physics [Boulder] (LASP), University of Colorado [Boulder], University of Southampton, Jodrell Bank Centre for Astrophysics, University of Manchester [Manchester], School of Physics and Astronomy [Southampton], Netherlands Institute for Radio Astronomy (ASTRON), Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), Oxford Astrophysics, University of Oxford [Oxford], Rhodes University, Grahamstown, CSIRO Astronomy and Space Science, Commonwealth Scientific and Industrial Research Organisation [Canberra] (CSIRO), Jacobs University [Bremen], Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Unité Scientifique de la Station de Nançay (USN), Université d'Orléans (UO)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), Universität Hamburg (UHH), Thüringer Landessternwarte Tautenburg (TLS), Radboud university [Nijmegen], Département de Géologie, Université de Montréal [Montréal], Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), PSL Research University (PSL)-PSL Research University (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), University of Hertfordshire [Hatfield] (UH), Max-Planck-Institut für Radioastronomie (MPIFR), Leiden Observatory [Leiden], Universiteit Leiden [Leiden], Institute for Mathematics, Astrophysics and Particle Physics (IMAPP), Curtin University [Perth], Planning and Transport Research Centre (PATREC), Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Victoria University of Wellington, Kapteyn Astronomical Institute [Groningen], University of Groningen [Groningen], SKA South Africa, Ska South Africa, Galaxies, Etoiles, Physique, Instrumentation (GEPI), PSL Research University (PSL)-PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), Department of Mathematics, The George Washington University, Washington State University (WSU), Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University [Cambridge]-Smithsonian Institution, Anton Pannekoek Institute for Astronomy, Observatoire de Paris - Site de Paris (OP), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Institute for Mathematics Applied to Geoscience, National Center for Atmospheric Research [Boulder] (NCAR), SRON Netherlands Institute for Space Research (SRON), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), University of Edinburgh, Leibniz-Institut für Astrophysik Potsdam (AIP), Max Planck Institute for Astrophysics, Max-Planck-Gesellschaft, Onsala Space Observatory, Dept. of Radio and Space Science, Chalmers University of Technology, Chalmers University of Technology [Göteborg], Ruhr-Universität Bochum [Bochum], University of Oulu, The Netherlands Institute for Radio Astronomy (ASTRON), 7990-AA Dwingeloo, Netherlands, Departament d'Astronomia i Meteorologia [Barcelona], Institut de Ciènces del Cosmos (ICC), Universitat de Barcelona (UB)-Universitat de Barcelona (UB), Center for Information Technology CIT, Université de Groningen, Interactions Son Musique Mouvement, Sciences et Technologies de la Musique et du Son (STMS), Université Pierre et Marie Curie - Paris 6 (UPMC)-IRCAM-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-IRCAM-Centre National de la Recherche Scientifique (CNRS), Rhodes University, Leibniz-Institut DSMZ-Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH / Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Cultures (DSMZ), Finca El Encin, Instituto Madrileño de Investigación y Desarrollo Rural, Agrario y Alimentario (IMIDRA), Argelander-Institut für Astronomie (AlfA), Rheinische Friedrich-Wilhelms-Universität Bonn, High Energy Astrophys. & Astropart. Phys (API, FNWI), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université d'Orléans (UO), Université de Montréal (UdeM), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National d’Études Spatiales [Paris] (CNES), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), 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), Department of Mathematics [George Washington University] (GW), The George Washington University (GW), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Pierre et Marie Curie - Paris 6 (UPMC), Universitat de Barcelona (UB), Institut de Recherche et Coordination Acoustique/Musique (IRCAM)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche et Coordination Acoustique/Musique (IRCAM)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), University of Oxford, Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Radboud University [Nijmegen], Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Universiteit Leiden, École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Harvard University-Smithsonian Institution, Stewart, A.J., Fender, R.P., Broderick, J.W., Hassall, T.E., Muñoz-Darias, T., Rowlinson, A., Swinbank, J.D., Staley, T.D., Molenaar, G.J., Scheers, B., Grobler, T.L., Pietka, M., Heald, G., McKean, J.P., Bell, M.E., Bonafede, A., Breton, R.P., Carbone, D., Cendes, Y., Clarke, A.O., Corbel, S., De Gasperin, F., Eislöffel, J., Falcke, H., Ferrari, C., Grießmeier, J.-M., Hardcastle, M.J., Heesen, V., Hessels, J.W.T., Horneffer, A., Iacobelli, M., Jonker, P., Karastergiou, A., Kokotanekov, G., Kondratiev, V.I., Kuniyoshi, M., Law, C.J., van Leeuwen, J., Markoff, S., Miller-Jones, J.C.A., Mulcahy, D., Orru, E., Pandey-Pommier, M., Pratley, L., Rol, E., Röttgering, H.J.A., Scaife, A.M.M., Shulevski, A., Sobey, C.A., Stappers, B.W., Tasse, C., van der Horst, A.J., van Velzen, S., van Weeren, R.J., Wijers, R.A.M.J., Wijnands, R., Wise, M., Zarka, P., Alexov, A., Anderson, J., Asgekar, A., Avruch, I.M., Bentum, M.J., Bernardi, G., Best, P., Breitling, F., Brüggen, M., Butcher, H.R., Ciardi, B., Conway, J.E., Corstanje, A., de Geus, E., Deller, A., Duscha, S., Frieswijk, W., Garrett, M.A., Gunst, A.W., Van Haarlem, M.P., Hoeft, M., Hörandel, J., Juette, E., Kuper, G., Loose, M., Maat, P., McFadden, R., McKay-Bukowski, D., Moldon, J., Munk, H., Norden, M.J., Paas, H., Polatidis, A.G., Schwarz, D., Sluman, J., Smirnov, O., Steinmetz, M., Thoudam, S., Toribio, M.C., Vermeulen, R., Vocks, C., Wijnholds, S.J., Wucknitz, O., Yatawatta, S., ITA, GBR, FRA, DEU, and NLD
Subjects: Astronomy, media_common.quotation_subject, interferometers [instrumentation], radio continuum: general, FOS: Physical sciences, techniques: image processing, 02 engineering and technology, Astrophysics, Low frequency, 01 natural sciences, Instrumentation: interferometer, Celestial pole, 0103 physical sciences, IR-102656, 0202 electrical engineering, electronic engineering, information engineering, instrumentation: interferometers, Instrumentation and Methods for Astrophysics (astro-ph.IM), 010303 astronomy & astrophysics, media_common, EWI-27481, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, image processing [techniques], METIS-320906, 020206 networking & telecommunications, Astronomy and Astrophysics, LOFAR, Limiting, Astronomy and Astrophysic, instrumentation: interferometers – techniques: image processing – radio continuum: general, radio, continuum: general, Observation duration, Space and Planetary Science, Sky, [SDU]Sciences of the Universe [physics], ComputingMethodologies_DOCUMENTANDTEXTPROCESSING, general [radio continuum], Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Instrumentation and Methods for Astrophysics
Abstract: We present the results of a four-month campaign searching for low-frequency radio transients near the North Celestial Pole with the Low-Frequency Array (LOFAR), as part of the Multifrequency Snapshot Sky Survey (MSSS). The data were recorded between 2011 December and 2012 April and comprised 2149 11-minute snapshots, each covering 175 deg^2. We have found one convincing candidate astrophysical transient, with a duration of a few minutes and a flux density at 60 MHz of 15-25 Jy. The transient does not repeat and has no obvious optical or high-energy counterpart, as a result of which its nature is unclear. The detection of this event implies a transient rate at 60 MHz of 3.9 (+14.7, -3.7) x 10^-4 day^-1 deg^-2, and a transient surface density of 1.5 x 10^-5 deg^-2, at a 7.9-Jy limiting flux density and ~10-minute time-scale. The campaign data were also searched for transients at a range of other time-scales, from 0.5 to 297 min, which allowed us to place a range of limits on transient rates at 60 MHz as a function of observation duration., 23 pages, 16 figures, 5 tables, accepted for publication in MNRAS
Published: 2016
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256. Imaging Jupiter's radiation belts down to 127 MHz with LOFAR

Author: Gianni Bernardi, Jörg R. Hörandel, A. G. Polatidis, Ashish Asgekar, A. Nelles, Angélica Sicard, H. Munk, R. J. van Weeren, Jason W. T. Hessels, D. McKay-Bukowski, I. de Pater, Matthias Hoeft, Oleg Smirnov, A. W. Gunst, Frank Breitling, Arthur Corstanje, Sebastien Hess, Quentin Nénon, Mark J. Bentum, J. van Leeuwen, R. C. Vermeulen, M. Loose, P. Zarka, H. J. A. Röttgering, P. Maat, M. J. Norden, M. Tagger, J. Moldón, F. de Gasperin, S. Bourdarie, Rene P. Breton, Annalisa Bonafede, John D. Swinbank, I. van Bemmel, Stephane Corbel, Martin Bell, V. I. Kondratiev, M. Pandey-Pommier, M. Iacobelli, James M. Anderson, Roberto Pizzo, Marcus Brüggen, Satyendra Thoudam, M. C. Toribio, Gerard H. Kuper, Antonia Rowlinson, Jochen Eislöffel, S. Duscha, Rebecca McFadden, M. A. Garrett, Daniel Santos-Costa, Julien N. Girard, Matthias Steinmetz, B. Ciardi, O. Wucknitz, J.-M. Grießmeier, M. Kuniyoshi, Ralph A. M. J. Wijers, Wilfred Frieswijk, Heino Falcke, C. Tasse, W. N. Brouw, S. Markov, Emanuela Orrú, H. Paas, Adam Deller, W. Reich, Dominik J. Schwarz, J. W. Broderick, E. Juette, G. Mann, Philip Best, C. Vocks, E. de Geus, Girard, J.N., Zarka, P., Tasse, C., Hess, S., De Pater, I., Santos-Costa, D., Nenon, Q., Sicard, A., Bourdarie, S., Anderson, J., Asgekar, A., Bell, M.E., Van Bemmel, I., Bentum, M.J., Bernardi, G., Best, P., Bonafede, A., Breitling, F., Breton, R.P., Broderick, J.W., Brouw, W.N., Brüggen, M., Ciardi, B., Corbel, S., Corstanje, A., De Gasperin, F., De Geus, E., Deller, A., Duscha, S., Eislöffel, J., Falcke, H., Frieswijk, W., Garrett, M.A., Grießmeier, J., Gunst, A.W., Hessels, J.W.T., Hoeft, M., Hörandel, J., Iacobelli, M., Juette, E., Kondratiev, V.I., Kuniyoshi, M., Kuper, G., Van Leeuwen, J., Loose, M., Maat, P., Mann, G., Markoff, S., McFadden, R., McKay-Bukowski, D., Moldon, J., Munk, H., Nelles, A., Norden, M.J., Orru, E., Paas, H., Pandey-Pommier, M., Pizzo, R., Polatidis, A.G., Reich, W., Röttgering, H., Rowlinson, A., Schwarz, D., Smirnov, O., Steinmetz, M., Swinbank, J., Tagger, M., Thoudam, S., Toribio, M.C., Vermeulen, R., Vocks, C., Van Weeren, R.J., Wijers, R.A.M.J., Wucknitz, O., Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), 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), Galaxies, Etoiles, Physique, Instrumentation (GEPI), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, ONERA - The French Aerospace Lab [Toulouse], ONERA, Netherlands Institute for Radio Astronomy (ASTRON), University of Southampton, Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE (UMR_7585)), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Royal Observatory Edinburgh (ROE), University of Edinburgh, Jacobs University [Bremen], Leibniz-Institut für Astrophysik Potsdam (AIP), Jodrell Bank Centre for Astrophysics (JBCA), University of Manchester [Manchester], Max Planck Institute for Astrophysics, Max-Planck-Gesellschaft, Radboud University [Nijmegen], Hamburger Sternwarte/Hamburg Observatory, Universität Hamburg (UHH), Thüringer Landessternwarte Tautenburg (TLS), Leiden Observatory [Leiden], Universiteit Leiden, Unité Scientifique de la Station de Nançay (USN), Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), Department of Pure Mathematics and Mathematical Statistics (DPMMS), Faculty of mathematics Centre for Mathematical Sciences [Cambridge] (CMS), University of Cambridge [UK] (CAM)-University of Cambridge [UK] (CAM), Ruhr-Universität Bochum [Bochum], Max-Planck-Institut für Radioastronomie (MPIFR), University of Oulu, University of Groningen [Groningen], Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), CSIRO Astronomy and Space Science, Commonwealth Scientific and Industrial Research Organisation [Canberra] (CSIRO), Universität Bielefeld, Rhodes University, Grahamstown, Leibniz-Institut DSMZ-Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH / Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Cultures (DSMZ), Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University-Smithsonian Institution, ANR-11-IDEX-0005,USPC,Université Sorbonne Paris Cité(2011), European Project: 228261,EC:FP7:ERC,ERC-2008-AdG,SPARSEASTRO(2009), ITA, GBR, FRA, DEU, NLD, Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Radboud university [Nijmegen], Universiteit Leiden [Leiden], Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Harvard University [Cambridge]-Smithsonian Institution, Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), PSL Research University (PSL)-PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), Jodrell Bank Centre for Astrophysics, Université d'Orléans (UO)-Observatoire des Sciences de l'Univers en région Centre (OSUC), PSL Research University (PSL)-PSL Research University (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), PSL Research University (PSL)-PSL Research University (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), DPMMS/CMS, University of Cambridge [UK] (CAM), ANR-11-IDEX-0005-02/10-LABX-0023,UnivEarthS,Earth - Planets - Universe: observation, modeling, transfer(2011), Astronomy, High Energy Astrophys. & Astropart. Phys (API, FNWI), and Faculty of Science
Subjects: radio continuum: planetary systems, Brightness, 010504 meteorology & atmospheric sciences, radio continuum: planetary, EWI-27447, Astronomy, Astrophysics::High Energy Astrophysical Phenomena, Magnetosphere, FOS: Physical sciences, Astrophysics, Electron, METIS-321662, 7. Clean energy, 01 natural sciences, Jupiter, symbols.namesake, 0103 physical sciences, Emission spectrum, IR-103183, 010303 astronomy & astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM), 0105 earth and related environmental sciences, Physics, Earth and Planetary Astrophysics (astro-ph.EP), [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Radio continuum: planetary system, Planets and satellites: magnetic field, Astronomy and Astrophysics, LOFAR, Astronomy and Astrophysic, planets and satellites: magnetic fields, Spectral flux density, 13. Climate action, Space and Planetary Science, Van Allen radiation belt, Techniques: interferometric, symbols, ComputingMethodologies_DOCUMENTANDTEXTPROCESSING, systems, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Earth and Planetary Astrophysics
Abstract: Context. Observing Jupiter's synchrotron emission from the Earth remains today the sole method to scrutinize the distribution and dynamical behavior of the ultra energetic electrons magnetically trapped around the planet (because in-situ particle data are limited in the inner magnetosphere). Aims. We perform the first resolved and low-frequency imaging of the synchrotron emission with LOFAR at 127 MHz. The radiation comes from low energy electrons (~1-30 MeV) which map a broad region of Jupiter's inner magnetosphere. Methods (see article for complete abstract) Results. The first resolved images of Jupiter's radiation belts at 127-172 MHz are obtained along with total integrated flux densities. They are compared with previous observations at higher frequencies and show a larger extent of the synchrotron emission source (>=4 $R_J$). The asymmetry and the dynamic of east-west emission peaks are measured and the presence of a hot spot at lambda_III=230 {\deg} $\pm$ 25 {\deg}. Spectral flux density measurements are on the low side of previous (unresolved) ones, suggesting a low-frequency turnover and/or time variations of the emission spectrum. Conclusions. LOFAR is a powerful and flexible planetary imager. The observations at 127 MHz depict an extended emission up to ~4-5 planetary radii. The similarities with high frequency results reinforce the conclusion that: i) the magnetic field morphology primarily shapes the brightness distribution of the emission and ii) the radiating electrons are likely radially and latitudinally distributed inside about 2 $R_J$. Nonetheless, the larger extent of the brightness combined with the overall lower flux density, yields new information on Jupiter's electron distribution, that may shed light on the origin and mode of transport of these particles., Comment: 10 pages, 12 figures, accepted for publication in A&A (27/11/2015) - abstract edited because of limited characters
Published: 2015
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257. The LOFAR Multifrequency Snapshot Sky Survey (MSSS): I. Survey description and first results

Author: G. H. Heald, R. F. Pizzo, E. Orrú, R. P. Breton, D. Carbone, C. Ferrari, M. J. Hardcastle, W. Jurusik, G. Macario, D. Mulcahy, D. Rafferty, A. Asgekar, M. Brentjens, R. A. Fallows, W. Frieswijk, M. C. Toribio, B. Adebahr, M. Arts, M. R. Bell, A. Bonafede, J. Bray, J. Broderick, T. Cantwell, P. Carroll, Y. Cendes, A. O. Clarke, J. Croston, S. Daiboo, F. de Gasperin, J. Gregson, J. Harwood, T. Hassall, V. Heesen, A. Horneffer, A. J. van der Horst, M. Iacobelli, V. Jelić, D. Jones, D. Kant, G. Kokotanekov, P. Martin, J. P. McKean, L. K. Morabito, B. Nikiel-Wroczyński, A. Offringa, V. N. Pandey, M. Pandey-Pommier, M. Pietka, L. Pratley, C. Riseley, A. Rowlinson, J. Sabater, A. M. M. Scaife, L. H. A. Scheers, K. Sendlinger, A. Shulevski, M. Sipior, C. Sobey, A. J. Stewart, A. Stroe, J. Swinbank, C. Tasse, J. Trüstedt, E. Varenius, S. van Velzen, N. Vilchez, R. J. van Weeren, S. Wijnholds, W. L. Williams, A. G. de Bruyn, R. Nijboer, M. Wise, A. Alexov, J. Anderson, I. M. Avruch, R. Beck, M. E. Bell, I. van Bemmel, M. J. Bentum, G. Bernardi, P. Best, F. Breitling, W. N. Brouw, M. Brüggen, H. R. Butcher, B. Ciardi, J. E. Conway, E. de Geus, A. de Jong, M. de Vos, A. Deller, R.-J. Dettmar, S. Duscha, J. Eislöffel, D. Engels, H. Falcke, R. Fender, M. A. Garrett, J. Grießmeier, A. W. Gunst, J. P. Hamaker, J. W. T. Hessels, M. Hoeft, J. Hörandel, H. A. Holties, H. Intema, N. J. Jackson, E. Jütte, A. Karastergiou, W. F. A. Klijn, V. I. Kondratiev, L. V. E. Koopmans, M. Kuniyoshi, G. Kuper, C. Law, J. van Leeuwen, M. Loose, P. Maat, S. Markoff, R. McFadden, D. McKay-Bukowski, M. Mevius, J. C. A. Miller-Jones, R. Morganti, H. Munk, A. Nelles, J. E. Noordam, M. J. Norden, H. Paas, A. G. Polatidis, W. Reich, A. Renting, H. Röttgering, A. Schoenmakers, D. Schwarz, J. Sluman, O. Smirnov, B. W. Stappers, M. Steinmetz, M. Tagger, Y. Tang, S. ter Veen, S. Thoudam, R. Vermeulen, C. Vocks, C. Vogt, R. A. M. J. Wijers, O. Wucknitz, S. Yatawatta, P. Zarka, Heald, G.H., Pizzo, R.F., Orrú, E., Breton, R.P., Carbone, D., Ferrari, C., Hardcastle, M.J., Jurusik, W., Macario, G., Mulcahy, D., Rafferty, D., Asgekar, A., Brentjens, M., Fallows, R.A., Frieswijk, W., Toribio, M.C., Adebahr, B., Arts, M., Bell, M.R., Bonafede, A., Bray, J., Broderick, J., Cantwell, T., Carroll, P., Cendes, Y., Clarke, A.O., Croston, J., Daiboo, S., De Gasperin, F., Gregson, J., Harwood, J., Hassall, T., Heesen, V., Horneffer, A., Van Der Horst, A.J., Iacobelli, M., Jelić, V., Jones, D., Kant, D., Kokotanekov, G., Martin, P., McKean, J.P., Morabito, L.K., Nikiel-Wroczyński, B., Offringa, A., Pandey, V.N., Pandey-Pommier, M., Pietka, M., Pratley, L., Riseley, C., Rowlinson, A., Sabater, J., Scaife, A.M.M., Scheers, L.H.A., Sendlinger, K., Shulevski, A., Sipior, M., Sobey, C., Stewart, A.J., Stroe, A., Swinbank, J., Tasse, C., Trüstedt, J., Varenius, E., Van Velzen, S., Vilchez, N., Van Weeren, R.J., Wijnholds, S., Williams, W.L., De Bruyn, A.G., Nijboer, R., Wise, M., Alexov, A., Anderson, J., Avruch, I.M., Beck, R., Bell, M.E., Van Bemmel, I., Bentum, M.J., Bernardi, G., Best, P., Breitling, F., Brouw, W.N., Brüggen, M., Butcher, H.R., Ciardi, B., Conway, J.E., De Geus, E., De Jong, A., De Vos, M., Deller, A., Dettmar, R.-J., Duscha, S., Eislöffel, J., Engels, D., Falcke, H., Fender, R., Garrett, M.A., Grießmeier, J., Gunst, A.W., Hamaker, J.P., Hessels, J.W.T., Hoeft, M., Hörandel, J., Holties, H.A., Intema, H., Jackson, N.J., Jütte, E., Karastergiou, A., Klijn, W.F.A., Kondratiev, V.I., Koopmans, L.V.E., Kuniyoshi, M., Kuper, G., Law, C., Van Leeuwen, J., Loose, M., Maat, P., Markoff, S., McFadden, R., McKay-Bukowski, D., Mevius, M., Miller-Jones, J.C.A., Morganti, R., Munk, H., Nelles, A., Noordam, J.E., Norden, M.J., Paas, H., Polatidis, A.G., Reich, W., Renting, A., Röttgering, H., Schoenmakers, A., Schwarz, D., Sluman, J., Smirnov, O., Stappers, B.W., Steinmetz, M., Tagger, M., Tang, Y., Ter Veen, S., Thoudam, S., Vermeulen, R., Vocks, C., Vogt, C., Wijers, R.A.M.J., Wucknitz, O., Yatawatta, S., Zarka, P., High Energy Astrophys. & Astropart. Phys (API, FNWI), Netherlands Institute for Radio Astronomy (ASTRON), Jodrell Bank Centre for Astrophysics (JBCA), University of Manchester [Manchester], University of Hertfordshire [Hatfield] (UH), Uniwersytet Jagielloński w Krakowie = Jagiellonian University (UJ), Joseph Louis LAGRANGE (LAGRANGE), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), University of Southampton, Jacobs University [Bremen], Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), 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), Hamburger Sternwarte/Hamburg Observatory, Universität Hamburg (UHH), School of Physics and Astronomy [Southampton], Leiden Observatory, Leiden University (Leiden Observatory), Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), CSIRO Astronomy and Space Science, Commonwealth Scientific and Industrial Research Organisation [Canberra] (CSIRO), Max-Planck-Institut für Radioastronomie (MPIFR), Laboratory for Atmospheric and Space Physics [Boulder] (LASP), University of Colorado [Boulder], Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University-Smithsonian Institution, Leiden Observatory [Leiden], Universiteit Leiden, SRON Netherlands Institute for Space Research (SRON), Leibniz-Institut für Astrophysik Potsdam (AIP), Research School of Astronomy and Astrophysics [Canberra] (RSAA), Australian National University (ANU), Max Planck Institute for Astrophysics, Max-Planck-Gesellschaft, Los Alamos National Laboratory (LANL), Astronomisches Institut der Ruhr-Universität Bochum, Ruhr-Universität Bochum [Bochum], Thüringer Landessternwarte Tautenburg (TLS), Radboud University [Nijmegen], Unité Scientifique de la Station de Nançay (USN), Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Leibniz-Institut DSMZ-Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH / Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Cultures (DSMZ), Institute for Mathematics, Astrophysics and Particle Physics (IMAPP), ANR-09-JCJC-0001,OPALES(2009), European Project: 247295,EC:FP7:ERC,ERC-2009-AdG,AARTFAAC(2010), European Project: 267697,EC:FP7:ERC,ERC-2010-AdG_20100224,4PI-SKY(2011), ITA, GBR, FRA, DEU, NLD, Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Centre d'études européennes et de politique comparée (CEE), Sciences Po (Sciences Po)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Harvard University [Cambridge]-Smithsonian Institution, Universiteit Leiden [Leiden], Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE (UMR_7585)), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Radboud university [Nijmegen], Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), Astronomy, Kapteyn Astronomical Institute, Jodrell Bank Centre for Astrophysics, Jagiellonian University [Krakow] (UJ), Université Nice Sophia Antipolis (... - 2019) (UNS), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Smithsonian Institution-Harvard University [Cambridge], Université d'Orléans (UO)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), PSL Research University (PSL)-PSL Research University (PSL)-Centre National d’Études Spatiales [Paris] (CNES), ANR-09-JCJC-0001,OPALES,nOn-thermal Processes in gALaxy cluStErs(2009), and Database Architectures
Subjects: 010504 meteorology & atmospheric sciences, Computer science, Astronomy, media_common.quotation_subject, FOS: Physical sciences, METIS-315082, 01 natural sciences, Radio spectrum, Radio continuum: general, surveys, 0103 physical sciences, radio continuum: general, Survey, GeneralLiterature_REFERENCE(e.g.,dictionaries,encyclopedias,glossaries), 010303 astronomy & astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM), 0105 earth and related environmental sciences, Remote sensing, media_common, Giant Metrewave Radio Telescope, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Astronomy and Astrophysics, LOFAR, Astronomy and Astrophysic, Square kilometre array, IR-98663, Sky, [SDU]Sciences of the Universe [physics], Space and Planetary Science, Experimental High Energy Physics, EWI-26540, Snapshot (computer storage), general [radio continuum], Astrophysics - Instrumentation and Methods for Astrophysics
Abstract: We present the Multifrequency Snapshot Sky Survey (MSSS), the first northern-sky LOFAR imaging survey. In this introductory paper, we first describe in detail the motivation and design of the survey. Compared to previous radio surveys, MSSS is exceptional due to its intrinsic multifrequency nature providing information about the spectral properties of the detected sources over more than two octaves (from 30 to 160 MHz). The broadband frequency coverage, together with the fast survey speed generated by LOFAR's multibeaming capabilities, make MSSS the first survey of the sort anticipated to be carried out with the forthcoming Square Kilometre Array (SKA). Two of the sixteen frequency bands included in the survey were chosen to exactly overlap the frequency coverage of large-area Very Large Array (VLA) and Giant Metrewave Radio Telescope (GMRT) surveys at 74 MHz and 151 MHz respectively. The survey performance is illustrated within the "MSSS Verification Field" (MVF), a region of 100 square degrees centered at J2000 (RA,Dec)=(15h,69deg). The MSSS results from the MVF are compared with previous radio survey catalogs. We assess the flux and astrometric uncertainties in the catalog, as well as the completeness and reliability considering our source finding strategy. We determine the 90% completeness levels within the MVF to be 100 mJy at 135 MHz with 108" resolution, and 550 mJy at 50 MHz with 166" resolution. Images and catalogs for the full survey, expected to contain 150,000-200,000 sources, will be released to a public web server. We outline the plans for the ongoing production of the final survey products, and the ultimate public release of images and source catalogs., Comment: 23 pages, 19 figures. Accepted for publication in Astronomy & Astrophysics. MSSS Verification Field images and catalog data may be downloaded from http://vo.astron.nl
Published: 2015
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258. Lunar occultation of the diffuse radio sky: LOFAR measurements between 35 and 80 MHz

Author: Vibor Jelić, Martin Bell, Gottfried Mann, Michael W. Wise, Gianni Bernardi, Wilfred Frieswijk, Jörg R. Hörandel, Garrelt Mellema, J. W. Broderick, J. Anderson, E. de Geus, George Heald, Y. Tang, K. M. B. Asad, M. J. Norden, Heino Falcke, Michiel A. Brentjens, Luitje Koopmans, V. I. Kondratiev, Arthur Corstanje, de Antonius Bruyn, A. Renting, Michel Tagger, Ben Stappers, Elizabeth Fernandez, F. de Gasperin, S. Kazemi, Emanuela Orrú, O. Martinez-Rubi, Rob Fender, A. Nelles, Oleg Smirnov, Stefan J. Wijnholds, P. Lambropoulos, A. R. Offringa, Annalisa Bonafede, Emma Chapman, Hannes Jensen, E. Juette, D. Engels, Sera Markoff, C. Toribio, Abhik Ghosh, F. B. Abdalla, Rebecca McFadden, Roberto Pizzo, Marco Iacobelli, Sarod Yatawatta, S. Daiboo, Satyendra Thoudam, W. Reich, D. McKay-Bukowski, Dominik J. Schwarz, D. D. Mulcahy, A. H. Patil, Frank Breitling, Jochen Eislöffel, B. Ciardi, Maaijke Mevius, Mark J. Bentum, C. Tasse, V. Veligatla, A. G. Polatidis, Matthias Steinmetz, S. Bus, Vishambhar Pandey, M. Kuniyoshi, Philippe Zarka, S. ter Veen, Adam Deller, Chiara Ferrari, A. W. Gunst, Ashish Asgekar, Matthias Hoeft, Philip Best, A. Shulevski, John D. Swinbank, H. Munk, Marcus Brüggen, Geraint Harker, Jean-Mathias Grießmeier, Tim Hassall, Christian Vocks, Saleem Zaroubi, Rajat M. Thomas, John McKean, Harvey Butcher, M. Pandey-Pommier, S. Duscha, Harish Vedantham, Richard Fallows, M. A. Garrett, H. J. A. Röttgering, Olaf Wucknitz, G. Kuper, Kapteyn Astronomical Institute [Groningen], University of Groningen [Groningen], UMR Peuplement Végétaux et Bioagresseurs en Milieu Tropical (UMR PVBMT - INRA), Institut National de la Recherche Agronomique (INRA), Netherlands Institute for Radio Astronomy (ASTRON), University College of London [London] (UCL), Laboratoire de Mécanique des Contacts et des Structures [Villeurbanne] (LaMCoS), Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Mécanique multiphysique pour les matériaux et les procédés (MULTIMAP), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Howard Hugues Medical Institute, Max Planck Institute for Astrophysics, Max-Planck-Gesellschaft, Departamento de Geologıa, Universidad de Santiago de Chile [Santiago] (USACH), Advanced Computing and Microelectronics Unit [Kolkata] (ACMU), Indian Statistical Institute [Kolkata], Department of Physics and Astronomy [UCL London], Stockholm University, Department of process and energy, Delft University of Technology (TU Delft), Department of Physics, University of Crete [Heraklion] (UOC), Institute of Electronic Structure and Laser, Foundation for Research and Technology - Hellas (FORTH), Stockholm Observatory Department of Astronomy, Department of Physics and Astronomy [Ghent], Ghent University [Belgium] (UGENT), Spatial Ecology and Epidemiology Group, University of Oxford [Oxford], Plant Ind, Hort Unit, Commonwealth Scientific and Industrial Research Organisation [Canberra] (CSIRO), Institute for Mathematics Applied to Geoscience, National Center for Atmospheric Research [Boulder] (NCAR), CSIRO Astronomy and Space Science, University of Edinburgh, Jacobs University [Bremen], Leibniz-Institut für Astrophysik Potsdam (AIP), University of Southampton, Radboud university [Nijmegen], Hamburger Sternwarte/Hamburg Observatory, Universität Hamburg (UHH), Metacohorts Consortium, Thüringer Landessternwarte Tautenburg (TLS), Département de Géologie, Université de Montréal [Montréal], Leiden Observatory [Leiden], Universiteit Leiden [Leiden], Unité Scientifique de la Station de Nançay (USN), Université d'Orléans (UO)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), PSL Research University (PSL)-PSL Research University (PSL)-Centre National d’Études Spatiales [Paris] (CNES), Ruhr-Universität Bochum [Bochum], Max-Planck-Institut für Radioastronomie (MPIFR), Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), University of Oulu, Jodrell Bank Centre for Astrophysics, University of Manchester [Manchester], Centre de Recherche Astrophysique de Lyon (CRAL), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon), Interactions Son Musique Mouvement, Sciences et Technologies de la Musique et du Son (STMS), Université Pierre et Marie Curie - Paris 6 (UPMC)-IRCAM-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-IRCAM-Centre National de la Recherche Scientifique (CNRS), Rhodes University, Leibniz-Institut DSMZ-Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH / Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Cultures (DSMZ), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Department of Astrophysics [Nijmegen], Institute for Mathematics, Astrophysics and Particle Physics (IMAPP), Radboud university [Nijmegen]-Radboud university [Nijmegen], Argelander-Institut für Astronomie (AlfA), Rheinische Friedrich-Wilhelms-Universität Bonn, Observatoire de Paris - Site de Paris (OP), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS), European Project: 258942,EC:FP7:ERC,ERC-2010-StG_20091028,FIRSTLIGHT(2010), Howard Hughes Medical Institute (HHMI), Universiteit Gent = Ghent University (UGENT), University of Oxford, Radboud University [Nijmegen], Université de Montréal (UdeM), Universiteit Leiden, Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche et Coordination Acoustique/Musique (IRCAM)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche et Coordination Acoustique/Musique (IRCAM)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Rhodes University, Grahamstown, 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), Radboud University [Nijmegen]-Radboud University [Nijmegen], Agence Nationale de la Recherche (ANR-09-JCJC-0001-01), Peuplements végétaux et bioagresseurs en milieu tropical (UMR PVBMT), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Université de La Réunion (UR), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Pierre et Marie Curie - Paris 6 (UPMC), Universiteit Gent = Ghent University [Belgium] (UGENT), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Vedantham, H.K., Koopmans, L.V.E., de Bruyn, A.G., Wijnholds, S.J., Brentjens, M., Abdalla, F.B., Asad, K.M.B., Bernardi, G., Bus, S., Chapman, E., Ciardi, B., Daiboo, S., Fernandez, E.R., Ghosh, A., Harker, G., Jelic, V., Jensen, H., Kazemi, S., Lambropoulos, P., Martinez-Rubi, O., Mellema, G., Mevius, M., Offringa, A.R., Pandey, V.N., Patil, A.H., Thomas, R.M., Veligatla, V., Yatawatta, S., Zaroubi, S., Anderson, J., Asgekar, A., Bell, M.E., Bentum, M.J., Best, P., Bonafede, A., Breitling, F., Broderick, J., Brüggen, M., Butcher, H.R., Corstanje, A., De Gasperin, F., De Geus, E., Deller, A., Duscha, S., Eislöffel, J., Engels, D., Falcke, H., Fallows, R.A., Fender, R., Ferrari, C., Frieswijk, W., Garrett, M.A., Grießmeier, J., Gunst, A.W., Hassall, T.E., Heald, G., Hoeft, M., Hörandel, J., Iacobelli, M., Juette, E., Kondratiev, V.I., Kuniyoshi, M., Kuper, G., Mann, G., Markoff, S., McFadden, R., McKay-Bukowski, D., McKean, J.P., Mulcahy, D.D., Munk, H., Nelles, A., Norden, M.J., Orru, E., Pandey-Pommier, M., Pizzo, R., Polatidis, A.G., Reich, W., Renting, A., Röttgering, H., Schwarz, D., Shulevski, A., Smirnov, O., Stappers, B.W., Steinmetz, M., Swinbank, J., Tagger, M., Tang, Y., Tasse, C., Ter Veen, S., Thoudam, S., Toribio, C., Vocks, C., Wise, M.W., Wucknitz, O., Zarka, P., Astronomy, Kapteyn Astronomical Institute, ITA, GBR, FRA, DEU, NLD, and High Energy Astrophys. & Astropart. Phys (API, FNWI)
Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO), media_common.quotation_subject, Astrophysics::High Energy Astrophysical Phenomena, Astronomy, first stars, observational [methods], FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, methods: observational, techniques: interferometric, Moon, dark ages, reionization, methods: observational – techniques: interferometric – Moon – cosmology: dark ages, Occultation, IR-98655, Reionization, Instrumentation and Methods for Astrophysics (astro-ph.IM), media_common, EWI-26150, Astroparticle physics, Physics, Epoch (reference date), Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy and Astrophysics, LOFAR, Astronomy and Astrophysic, Universe, interferometric [techniques], Dark ages, reionization, first star, Sky, Space and Planetary Science, [SDU]Sciences of the Universe [physics], Physics::Space Physics, ComputingMethodologies_DOCUMENTANDTEXTPROCESSING, Dark Ages, Astrophysics::Earth and Planetary Astrophysics, METIS-314921, Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: We present radio observations of the Moon between $35$ and $80$ MHz to demonstrate a novel technique of interferometrically measuring large-scale diffuse emission extending far beyond the primary beam (global signal) for the first time. In particular, we show that (i) the Moon appears as a negative-flux source at frequencies $35z>12$) and the Epoch of Reionization ($12>z>5$)., Comment: 15 pages, 11 figures, 1 table
Published: 2015
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259. Probing Atmospheric Electric Fields in Thunderstorms through Radio Emission from Cosmic-Ray-Induced Air Showers

Author: A. Alexov, M. Serylak, M. A. Garrett, E. Juette, B. Ciardi, C. Tasse, C. Koehn, M. Kuniyoshi, Dominik J. Schwarz, M. C. Toribio, A. Nelles, F. Breitling, Jean-Mathias Grießmeier, John McKean, John D. Swinbank, Jochen Eislöffel, W. Reich, J. Moldon, Maaijke Mevius, Marcus Brüggen, Casper Rutjes, R. J. van Weeren, Emanuela Orrú, J. W. Broderick, A. G. Polatidis, Rebecca McFadden, D. McKay-Bukowski, E. de Geus, Heino Falcke, M. J. Norden, V. I. Kondratiev, Harvey Butcher, M. Pandey-Pommier, Philip Best, Pim Schellart, Jason W. T. Hessels, Philippe Zarka, S. Duscha, Richard Fallows, Arthur Corstanje, Matthias Steinmetz, H. Paas, Ute Ebert, G. Kuper, Olaf Scholten, H. J. A. Röttgering, Oleg Smirnov, R. Vermeulen, Annalisa Bonafede, Mark J. Bentum, Michel Tagger, Michael W. Wise, Jörg P. Rachen, Gianni Bernardi, Jörg R. Hörandel, H. A. Holties, Olaf Wucknitz, T. N. G. Trinh, J. E. Enriquez, S. ter Veen, A. W. Gunst, M. de Vos, I. M. Avruch, Laura Rossetto, James M. Anderson, Gottfried Mann, Stijn Buitink, Roberto Pizzo, Wilfred Frieswijk, Christian Vocks, Satyendra Thoudam, Anna M. M. Scaife, Matthias Hoeft, George Heald, Department of Astrophysics [Nijmegen], Institute for Mathematics, Astrophysics and Particle Physics (IMAPP), Radboud University [Nijmegen]-Radboud University [Nijmegen], KVI Center for Advanced Radiation Technology, University of Groningen [Groningen], Netherlands Institute for Radio Astronomy (ASTRON), Max-Planck-Institut für Radioastronomie (MPIFR), National Institute for Subatomic Physics [Amsterdam] (NIKHEF), Vrije Universiteit Brussel (VUB), Centrum Wiskunde & Informatica (CWI), Space Telescope Science Institute (STSci), GeoForschungsZentrum - Helmholtz-Zentrum Potsdam (GFZ), SRON Netherlands Institute for Space Research (SRON), Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University-Smithsonian Institution, Institute for Astronomy [Edinburgh] (IfA), University of Edinburgh, University of Hamburg, Leibniz-Institut für Astrophysik Potsdam (AIP), Oxford Astrophysics, University of Oxford, University of Southampton, Research School of Astronomy and Astrophysics [Canberra] (RSAA), Australian National University (ANU), Max Planck Institute for Astrophysics, Max-Planck-Gesellschaft, Thüringer Landessternwarte Tautenburg (TLS), Unité Scientifique de la Station de Nançay (USN), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Astronomisches Institut der Ruhr-Universität Bochum, Ruhr-Universität Bochum [Bochum], National Astronomical Observatory of Japan (NAOJ), University of Oulu, Center for Information Technology CIT, Université de Groningen, Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Leiden Observatory [Leiden], Universiteit Leiden, Universität Bielefeld = Bielefeld University, SKA South Africa, Ska South Africa, Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), 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), NOVA, SNN and FOM as well as from NWO, VENI Grant No. 639-041-130, European Project: 227610,EC:FP7:ERC,ERC-2008-AdG,LOFAR-AUGER(2009), High Energy Astrophys. & Astropart. Phys (API, FNWI), Schellart, P., Trinh, T.N.G., Buitink, S., Corstanje, A., Enriquez, J.E., Falcke, H., Hörandel, J.R., Nelles, A., Rachen, J.P., Rossetto, L., Scholten, O., Ter Veen, S., Thoudam, S., Ebert, U., Koehn, C., Rutjes, C., Alexov, A., Anderson, J.M., Avruch, I.M., Bentum, M.J., Bernardi, G., Best, P., Bonafede, A., Breitling, F., Broderick, J.W., Brüggen, M., Butcher, H.R., Ciardi, B., De Geus, E., De Vos, M., Duscha, S., Eislöffel, J., Fallows, R.A., Frieswijk, W., Garrett, M.A., Grießmeier, J., Gunst, A.W., Heald, G., Hessels, J.W.T., Hoeft, M., Holties, H.A., Juette, E., Kondratiev, V.I., Kuniyoshi, M., Kuper, G., Mann, G., McFadden, R., McKay-Bukowski, D., McKean, J.P., Mevius, M., Moldon, J., Norden, M.J., Orru, E., Paas, H., Pandey-Pommier, M., Pizzo, R., Polatidis, A.G., Reich, W., Röttgering, H., Scaife, A.M.M., Schwarz, D.J., Serylak, M., Smirnov, O., Steinmetz, M., Swinbank, J., Tagger, M., Tasse, C., Toribio, M.C., Van Weeren, R.J., Vermeulen, R., Vocks, C., Wise, M.W., Wucknitz, O., Zarka, P., Kapteyn Astronomical Institute, Elementary Processes in Gas Discharges, Center for Wireless Technology Eindhoven, Physics, Astronomy and Astrophysics Research Group, Elementary Particle Physics, Multiscale Dynamics, Radboud university [Nijmegen]-Radboud university [Nijmegen], Harvard University [Cambridge]-Smithsonian Institution, University of Oxford [Oxford], Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université d'Orléans (UO), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National d’Études Spatiales [Paris] (CNES), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Universiteit Leiden [Leiden], Fakultät für Physik, Universität Bielefeld, Universität Bielefeld, ITA, GBR, FRA, DEU, and NLD
Subjects: Astronomy, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, General Physics and Astronomy, Cosmic ray, Astrophysics, Neutrino muon pion and other elementary particles, Physics and Astronomy (all), cosmic rays, IR-99169, Atmospheric electricity lightning, Electric field, Extensive air showers, Instrumentation and Methods for Astrophysics (astro-ph.IM), METIS-315601, Physics::Atmospheric and Oceanic Physics, High Energy Astrophysical Phenomena (astro-ph.HE), Earth and Planetary Astrophysics (astro-ph.EP), Astroparticle physics, Physics, [PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, EWI-26542, LOFAR, Polarization (waves), SIMULATIONS, COREAS, 13. Climate action, Experimental High Energy Physics, Thunderstorm, ComputingMethodologies_DOCUMENTANDTEXTPROCESSING, ARRAY, Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Earth and Planetary Astrophysics
Abstract: We present measurements of radio emission from cosmic ray air showers that took place during thunderstorms. The intensity and polarization patterns of these air showers are radically different from those measured during fair-weather conditions. With the use of a simple two-layer model for the atmospheric electric field, these patterns can be well reproduced by state-of-the-art simulation codes. This in turn provides a novel way to study atmospheric electric fields., 6 pages, 3 figures, accepted for publication in Physical Review Letters
Published: 2015
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260. The shape of the radio wavefront of extensive air showers as measured with LOFAR

Author: J. E. Enriquez, Wilfred Frieswijk, Y. Tang, Anna M. M. Scaife, Emanuela Orrú, Gottfried Mann, M. van den Akker, H. J. A. Röttgering, Stefan J. Wijnholds, W. Reich, Mark J. Bentum, Olaf Wucknitz, Sarod Yatawatta, Heino Falcke, Frank Breitling, Chiara Ferrari, D. Engels, Adam Stewart, Aris Karastergiou, Richard Fallows, Maria Krause, P. Maat, A. Horneffer, C. Toribio, Michel Tagger, M. A. Garrett, Jörg P. Rachen, Gianni Bernardi, Jörg R. Hörandel, M. J. Norden, Vishambhar Pandey, Matthias Hoeft, R. J. van Weeren, Jochen Eislöffel, V. I. Kondratiev, D. McKay-Bukowski, Marco Iacobelli, F. de Gasperin, A. Alexov, J.-M. Grießmeier, Maaijke Mevius, T. N. G. Trinh, G. Kuper, A. G. Polatidis, Arthur Corstanje, A. Nelles, E. Juette, I. M. Avruch, Roberto Pizzo, Olaf Scholten, Oleg Smirnov, J. Kohler, H. Paas, Satyendra Thoudam, M. de Vos, Dominik J. Schwarz, Rene C. Vermeulen, P. Zarka, Annalisa Bonafede, J. P. Hamaker, Martin Bell, J. Anderson, Matthias Steinmetz, S. ter Veen, Rebecca McFadden, A. W. Gunst, Stijn Buitink, Christian Vocks, J. W. Broderick, E. de Geus, John D. Swinbank, Harvey Butcher, M. Pandey-Pommier, S. Duscha, B. Ciardi, C. Tasse, M. Kuniyoshi, H. Munk, Marcus Brüggen, Philip Best, Pim Schellart, Institute for Mathematics, Astrophysics and Particle Physics (IMAPP), Radboud University [Nijmegen], Netherlands Institute for Radio Astronomy (ASTRON), Max-Planck-Institut für Extraterrestrische Physik (MPE), Leibniz-Institut für Astrophysik Potsdam (AIP), SRON Netherlands Institute for Space Research (SRON), Delft University of Technology (TU Delft), University of Edinburgh, University of Southampton, Universität Hamburg (UHH), Thüringer Landessternwarte Tautenburg (TLS), Joseph Louis LAGRANGE (LAGRANGE), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Unité Scientifique de la Station de Nançay (USN), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Universiteit Leiden, Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Leiden Observatory [Leiden], Department of Astrophysical Sciences [Princeton], Princeton University, Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), Netherlands Research School for Astronomy (NOVA), the Samenwerkingsverband Noord-Nederland (SNN) and the Foundation for Fundamental Research on Matter (FOM) as well as support from the Netherlands Organization for Scientific Research (NWO), VENI grant 639-041-130, European Project: 227610,EC:FP7:ERC,ERC-2008-AdG,LOFAR-AUGER(2009), ITA, GBR, FRA, DEU, NLD, Corstanje, A., Schellart, P., Nelles, A., Buitink, S., Enriquez, J.E., Falcke, H., Frieswijk, W., Hörandel, J.R., Krause, M., Rachen, J.P., Scholten, O., Ter Veen, S., Thoudam, S., Trinh, T.N.G., Van Den Akker, M., Alexov, A., Anderson, J., Avruch, I.M., Bell, M.E., Bentum, M.J., Bernardi, G., Best, P., Bonafede, A., Breitling, F., Broderick, J., Brüggen, M., Butcher, H.R., Ciardi, B., De Gasperin, F., De Geus, E., De Vos, M., Duscha, S., Eislöffel, J., Engels, D., Fallows, R.A., Ferrari, C., Garrett, M.A., Grießmeier, J., Gunst, A.W., Hamaker, J.P., Hoeft, M., Horneffer, A., Iacobelli, M., Juette, E., Karastergiou, A., Kohler, J., Kondratiev, V.I., Kuniyoshi, M., Kuper, G., Maat, P., Mann, G., McFadden, R., McKay-Bukowski, D., Mevius, M., Munk, H., Norden, M.J., Orru, E., Paas, H., Pandey-Pommier, M., Pandey, V.N., Pizzo, R., Polatidis, A.G., Reich, W., Röttgering, H., Scaife, A.M.M., Schwarz, D., Smirnov, O., Stewart, A., Steinmetz, M., Swinbank, J., Tagger, M., Tang, Y., Tasse, C., Toribio, C., Vermeulen, R., Vocks, C., Van Weeren, R.J., Wijnholds, S.J., Wucknitz, O., Yatawatta, S., Zarka, P., Radboud university [Nijmegen], Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), Universiteit Leiden [Leiden], École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Astronomy, Research unit Astroparticle Physics, and High Energy Astrophys. & Astropart. Phys (API, FNWI)
Subjects: Physics::Instrumentation and Detectors, Astronomy, Astrophysics::High Energy Astrophysical Phenomena, Extensive air shower, FOS: Physical sciences, Cosmic ray, Astrophysics, 01 natural sciences, Radio telescope, Optics, 0103 physical sciences, Extensive air showers, Ultra-high-energy cosmic ray, Radio emission, 010303 astronomy & astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM), Cosmic rays, Wavefront, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), 010308 nuclear & particles physics, business.industry, [SDU.ASTR.HE]Sciences of the Universe [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy and Astrophysics, LOFAR, Air shower, Wavefront shape, ComputingMethodologies_DOCUMENTANDTEXTPROCESSING, Hyperboloid, business, Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Instrumentation and Methods for Astrophysics, Shape analysis (digital geometry)
Abstract: Extensive air showers, induced by high energy cosmic rays impinging on the Earth's atmosphere, produce radio emission that is measured with the LOFAR radio telescope. As the emission comes from a finite distance of a few kilometers, the incident wavefront is non-planar. A spherical, conical or hyperbolic shape of the wavefront has been proposed, but measurements of individual air showers have been inconclusive so far. For a selected high-quality sample of 161 measured extensive air showers, we have reconstructed the wavefront by measuring pulse arrival times to sub-nanosecond precision in 200 to 350 individual antennas. For each measured air shower, we have fitted a conical, spherical, and hyperboloid shape to the arrival times. The fit quality and a likelihood analysis show that a hyperboloid is the best parametrization. Using a non-planar wavefront shape gives an improved angular resolution, when reconstructing the shower arrival direction. Furthermore, a dependence of the wavefront shape on the shower geometry can be seen. This suggests that it will be possible to use a wavefront shape analysis to get an additional handle on the atmospheric depth of the shower maximum, which is sensitive to the mass of the primary particle., Accepted for publication in Astroparticle Physics
Published: 2014
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261. The LOFAR pilot surveys for pulsars and fast radio transients

Author: K. Zagkouris, Stefan Oslowski, C. Schrijvers, Michel Tagger, A. Noutsos, Jean-Mathias Grießmeier, John D. Swinbank, Simon Cooper, Dominik J. Schwarz, Rob Fender, P. Zarka, Heino Falcke, Philip Best, V. I. Kondratiev, D. McKay-Bukowski, Charlotte Sobey, Arthur Corstanje, Gerard H. Kuper, Christian Vocks, T. Coenen, M. A. Garrett, Y. Tang, M. Serylak, T. E. Hassall, Oleg Smirnov, Gottfried Mann, Olaf Wucknitz, Anna M. M. Scaife, Jason W. T. Hessels, J. Sluman, Aris Karastergiou, Gianni Bernardi, Mark J. Bentum, Michael Kramer, M. Pilia, George Heald, S. ter Veen, A. W. Gunst, H. Munk, H. J. A. Röttgering, A. S. van Amesfoort, E. de Geus, Satyendra Thoudam, Marcus Brüggen, C. Tasse, Harvey Butcher, John McKean, Emanuela Orru, Casey J. Law, M. Kuniyoshi, Chiara Ferrari, F. Breitling, Annalisa Bonafede, Joeri van Leeuwen, M. Pandey-Pommier, A. Zensus, James M. Anderson, Antonia Rowlinson, Ashish Asgekar, C. Toribio, R. Vermeulen, Joris P. W. Verbiest, Evan Keane, Matthias Hoeft, Vishal Gajjar, Jochen Eislöffel, S. Duscha, H. Paas, A. G. Polatidis, A. Alexov, Rebecca McFadden, Benedetta Ciardi, Stefan J. Wijnholds, J. W. Broderick, Richard Fallows, Wolfgang Reich, B. W. Stappers, A. Renting, F. de Gasperin, Adam T. Deller, W. Frieswijk, Martin Bell, Anna V. Bilous, R. J. van Weeren, I. M. Avruch, E. Juette, Patrick Weltevrede, J. P. Hamaker, A. J. van der Horst, Rene P. Breton, Kapteyn Astronomical Institute, Astronomy, Netherlands Institute for Radio Astronomy (ASTRON), University of Amsterdam [Amsterdam] (UvA), Jodrell Bank Centre for Astrophysics (JBCA), University of Manchester [Manchester], University of Southampton, Institute for Mathematics, Astrophysics and Particle Physics (IMAPP), Radboud University [Nijmegen], Max-Planck-Institut für Radioastronomie (MPIFR), Unité Scientifique de la Station de Nançay (USN), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), University of Oxford, Universität Bielefeld, Leibniz-Institut für Astrophysik Potsdam (AIP), SRON Netherlands Institute for Space Research (SRON), Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University-Smithsonian Institution, University of Edinburgh, Jacobs University [Bremen], Universität Hamburg (UHH), Max Planck Institute for Astrophysics, Max-Planck-Gesellschaft, Thüringer Landessternwarte Tautenburg (TLS), Joseph Louis LAGRANGE (LAGRANGE), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Leiden Observatory [Leiden], Universiteit Leiden, Ruhr-Universität Bochum [Bochum], Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Oulu, Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), School of Physics and Astronomy [Southampton], Rhodes University, Grahamstown, 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), ANR-09-JCJC-0001,OPALES(2009), European Project: 224838,EC:FP7:PEOPLE,FP7-PEOPLE-2007-4-3-IRG,PULSARS WITH LOFAR(2008), High Energy Astrophys. & Astropart. Phys (API, FNWI), Radboud university [Nijmegen], Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), University of Oxford [Oxford], Harvard University [Cambridge]-Smithsonian Institution, Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Universiteit Leiden [Leiden], École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Jodrell Bank Centre for Astrophysics, Université d'Orléans (UO)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), PSL Research University (PSL)-PSL Research University (PSL)-Centre National d’Études Spatiales [Paris] (CNES), Smithsonian Institution-Harvard University [Cambridge], Université Nice Sophia Antipolis (... - 2019) (UNS), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), ANR-09-JCJC-0001,OPALES,nOn-thermal Processes in gALaxy cluStErs(2009), Coenen, Thij, Van Leeuwen, Joeri, Hessels, Jason W. T., Stappers, Ben W., Kondratiev, Vladislav I., Alexov, A., Breton, R.P., Bilous, A., Cooper, S., Falcke, H., Fallows, R.A., Gajjar, V., Grießmeier, J.-M., Hassall, T.E., Karastergiou, A., Keane, E.F., Kramer, M., Kuniyoshi, M., Noutsos, A., Osłowski, S., Pilia, M., Serylak, M., Schrijvers, C., Sobey, C., Ter Veen, S., Verbiest, J., Weltevrede, P., Wijnholds, S., Zagkouris, K., Van Amesfoort, A.S., Anderson, J., Asgekar, A., Avruch, I.M., Bell, M.E., Bentum, M.J., Bernardi, G., Best, P., Bonafede, A., Breitling, F., Broderick, J., Brüggen, M., Butcher, H.R., Ciardi, B., Corstanje, A., Deller, A., Duscha, S., Eislöffel, J., Fender, R., Ferrari, C., Frieswijk, W., Garrett, M.A., De Gasperin, F., De Geus, E., Gunst, A.W., Hamaker, J.P., Heald, G., Hoeft, M., Van Der Horst, A., Juette, E., Kuper, G., Law, C., Mann, G., McFadden, R., McKay-Bukowski, D., McKean, J.P., Munk, H., Orru, E., Paas, H., Pandey-Pommier, M., Polatidis, A.G., Reich, W., Renting, A., Röttgering, H., Rowlinson, A., Scaife, A.M.M., Schwarz, D., Sluman, J., Smirnov, O., Swinbank, J., Tagger, M., Tang, Y., Tasse, C., Thoudam, S., Toribio, C., Vermeulen, R., Vocks, C., Van Weeren, R.J., Wucknitz, O., Zarka, P., and Zensus, A.
Subjects: EWI-25426, Aperture array, media_common.quotation_subject, Astronomy, Pilot survey, SPECTRAL INDEX, FOS: Physical sciences, Astrophysics, general [pulsars], METIS-309729, MHZ, Pulsar, surveys, pulsars: general, BURSTS, Survey, Telescope, POPULATION, Solar and Stellar Astrophysics (astro-ph.SR), media_common, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), [PHYS]Physics [physics], ORIGIN, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Astronomy and Astrophysics, telescopes, BINARY, LOFAR, Astronomy and Astrophysic, IR-93231, Astrophysics - Solar and Stellar Astrophysics, Sky, Space and Planetary Science, DISCOVERY, ComputingMethodologies_DOCUMENTANDTEXTPROCESSING, STATE CHANGE, Antenna (radio), ALLEN TELESCOPE ARRAY, EMISSION, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - High Energy Astrophysical Phenomena
Abstract: We have conducted two pilot surveys for radio pulsars and fast transients with the Low-Frequency Array (LOFAR) around 140 MHz and here report on the first low-frequency fast-radio burst limit and the discovery of two new pulsars. The first survey, the LOFAR Pilot Pulsar Survey (LPPS), observed a large fraction of the northern sky, ~1.4 x 10^4 sq. deg, with 1-hr dwell times. Each observation covered ~75 sq. deg using 7 independent fields formed by incoherently summing the high-band antenna fields. The second pilot survey, the LOFAR Tied-Array Survey (LOTAS), spanned ~600 sq. deg, with roughly a 5-fold increase in sensitivity compared with LPPS. Using a coherent sum of the 6 LOFAR "Superterp" stations, we formed 19 tied-array beams, together covering 4 sq. deg per pointing. From LPPS we derive a limit on the occurrence, at 142 MHz, of dispersed radio bursts of < 150 /day/sky, for bursts brighter than S > 107 Jy for the narrowest searched burst duration of 0.66 ms. In LPPS, we re-detected 65 previously known pulsars. LOTAS discovered two pulsars, the first with LOFAR or any digital aperture array. LOTAS also re-detected 27 previously known pulsars. These pilot studies show that LOFAR can efficiently carry out all-sky surveys for pulsars and fast transients, and they set the stage for further surveying efforts using LOFAR and the planned low-frequency component of the Square Kilometer Array., 18 pages, 10 figures, accepted for A&A
Published: 2014
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262. The role of NYMEX in oil price risk management

Author: McFadden, R
Published: 1988

263. Wide-field LOFAR imaging of the field around the double-double radio galaxy B1834+620

Author: E. Orrù, S. van Velzen, R. F. Pizzo, S. Yatawatta, R. Paladino, M. Iacobelli, M. Murgia, H. Falcke, R. Morganti, A. G. de Bruyn, C. Ferrari, J. Anderson, A. Bonafede, D. Mulcahy, A. Asgekar, I. M. Avruch, R. Beck, M. E. Bell, I. van Bemmel, M. J. Bentum, G. Bernardi, P. Best, F. Breitling, J. W. Broderick, M. Brüggen, H. R. Butcher, B. Ciardi, J. E. Conway, A. Corstanje, E. de Geus, A. Deller, S. Duscha, J. Eislöffel, D. Engels, W. Frieswijk, M. A. Garrett, J. Grießmeier, A. W. Gunst, J. P. Hamaker, G. Heald, M. Hoeft, A. J. van der Horst, H. Intema, E. Juette, J. Kohler, V. I. Kondratiev, M. Kuniyoshi, G. Kuper, M. Loose, P. Maat, G. Mann, S. Markoff, R. McFadden, D. McKay-Bukowski, G. Miley, J. Moldon, G. Molenaar, H. Munk, A. Nelles, H. Paas, M. Pandey-Pommier, V. N. Pandey, G. Pietka, A. G. Polatidis, W. Reich, H. Röttgering, A. Rowlinson, A. Scaife, A. Schoenmakers, D. Schwarz, M. Serylak, A. Shulevski, O. Smirnov, M. Steinmetz, A. Stewart, J. Swinbank, M. Tagger, C. Tasse, S. Thoudam, M. C. Toribio, R. Vermeulen, C. Vocks, R. J. van Weeren, R. A. M. J. Wijers, M. W. Wise, O. Wucknitz, High Energy Astrophys. & Astropart. Phys (API, FNWI), Kapteyn Astronomical Institute, Astronomy, Orru, E., Van Velzen, S., Pizzo, R.F., Yatawatta, S., Paladino, R., Iacobelli, M., Murgia, M., Falcke, H., Morganti, R., De Bruyn, A.G., Ferrari, C., Anderson, J., Bonafede, A., Mulcahy, D., Asgekar, A., Avruch, I.M., Beck, R., Bell, M.E., Van Bemmel, I., Bentum, M.J., Bernardi, G., Best, P., Breitling, F., Broderick, J.W., Bruggen, M., Butcher, H.R., Ciardi, B., Conway, J.E., Corstanje, A., De Geus, E., Deller, A., Duscha, S., Eisloffel, J., Engels, D., Frieswijk, W., Garrett, M.A., Grießmeier, J., Gunst, A.W., Hamaker, J.P., Heald, G., Hoeft, M., Van Der Horst, A.J., Intema, H., Juette, E., Kohler, J., Kondratiev, V.I., Kuniyoshi, M., Kuper, G., Loose, M., Maat, P., Mann, G., Markoff, S., McFadden, R., McKay-BGBRowski, D., Miley, G., Moldon, J., Molenaar, G., Munk, H., Nelles, A., Paas, H., Pandey-Pommier, M., Pandey, V.N., Pietka, G., Polatidis, A.G., Reich, W., Rottgering, H., Rowlinson, A., Scaife, A., Schoenmakers, A., Schwarz, D., Serylak, M., Shulevski, A., Smirnov, O., Steinmetz, M., Stewart, A., Swinbank, J., Tagger, M., Tasse, C., Thoudam, S., Toribio, M.C., Vermeulen, R., Vocks, C., Van Weeren, R.J., Wijers, R.A.M.J., Wise, M.W., and Wucknitz, O.
Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO), Radio galaxy, Astrophysics::High Energy Astrophysical Phenomena, interferometers [instrumentation], galaxies: active, Population, FOS: Physical sciences, Field of view, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Astroparticle physic, Radio continuum: galaxie, 01 natural sciences, Instrumentation: interferometer, law.invention, Telescope, law, 0103 physical sciences, Bow shock (aerodynamics), instrumentation: interferometers, education, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, radio continuum: galaxies, Physics, education.field_of_study, Accretion (meteorology), 010308 nuclear & particles physics, Astronomy and Astrophysics, LOFAR, Astronomy and Astrophysic, radiation mechanisms: non-thermal, non-thermal [radiation mechanisms], Astrophysics - Astrophysics of Galaxies, galaxies [radio continuum], Redshift, interferometric [techniques], techniques: interferometric, astroparticle physics, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), active [galaxies], Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: The existence of double-double radio galaxies (DDRGs) is evidence for recurrent jet activity in AGN, as expected from standard accretion models. A detailed study of these rare sources provides new perspectives for investigating the AGN duty cycle, AGN-galaxy feedback, and accretion mechanisms. Large catalogues of radio sources provide statistical information about the evolution of the radio-loud AGN population out to high redshifts. Using wide-field imaging with the LOFAR telescope, we study both a well-known DDRG as well as a large number of radio sources in the field of view. We present a high resolution image of the DDRG B1834+620 obtained at 144 MHz using LOFAR commissioning data. Our image covers about 100 square degrees and contains over 1000 sources. The four components of the DDRG B1834+620 have been resolved for the first time at 144 MHz. Inner lobes were found to point towards the direction of the outer lobes, unlike standard FR~II sources. Polarized emission was detected in the northern outer lobe. The high spatial resolution allows the identification of a large number of small double-lobed radio sources; roughly 10% of all sources in the field are doubles with a separation smaller than 1 arcmin. The spectral fit of the four components is consistent with a scenario in which the outer lobes are still active or the jets recently switched off, while emission of the inner lobes is the result of a mix-up of new and old jet activity. From the presence of the newly extended features in the inner lobes of the DDRG, we can infer that the mechanism responsible for their formation is the bow shock that is driven by the newly launched jet. We find that the density of the small doubles exceeds the density of FR-II sources with similar properties at 1.4 GHz, but this difference becomes smaller for low flux densities., Comment: 13 pages, 8 figures, Accepted for publication in Astronomy & Astrophysics
Published: 2015
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264. Nymex activity keeps growing

Author: McFadden, R
Published: 1989

265. Detecting ultra high energy neutrinos with LOFAR

Author: Mevius, M., Buitink, S., Falcke, H., Hörandel, J., James, C.W., McFadden, R., Scholten, O., Singh, K., Stappers, B., and ter Veen, S.
Subjects: *NEUTRINO astrophysics, *COSMIC rays, *RADIO telescopes, *CHERENKOV radiation, *NUCLEAR research, *EARTH (Planet)
Abstract: Abstract: The NuMoon project aims to detect signals of Ultra High Energy (UHE) Cosmic Rays with radio telescopes on Earth using the Lunar Cherenkov technique at low frequencies . The advantage of using low frequencies is the much larger effective detecting volume, with as trade-off the cut-off in sensitivity at lower energies. A first upper limit on the UHE neutrino flux from data of the Westerbork Radio Telescope (WSRT) has been published, while a second experiment, using the new LOFAR telescope, is in preparation. The advantages of LOFAR over WSRT are the larger collecting area, the better pointing accuracy and the use of ring buffers, which allow the implementation of a sophisticated self-trigger algorithm. The expected sensitivity of LOFAR reaches flux limits within the range of some theoretical production models. [Copyright &y& Elsevier]
Published: 2012
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266. Treatment of Refractory Gastrointestinal Bleeding in Patients With Portal Hypertension: A Case Series and Treatment Algorithm.

Author: Balogh J, Gordon-Burroughs S, Schwarz P, Galati J, McFadden RA, Cusick M, Snyder MJ, Bailey HR, Weiner M, Wong A, Ochoa RA, Saharia A, Gaber AO, and Ghobrial RM
Subjects: Esophageal and Gastric Varices complications, Gastrointestinal Hemorrhage etiology, Humans, Hypertension, Portal therapy, Ligation, Male, Middle Aged, Algorithms, Disease Management, Esophageal and Gastric Varices therapy, Gastrointestinal Hemorrhage therapy, Hypertension, Portal complications
Abstract: In patients with portal hypertension, ectopic varices can develop at any site along the gastrointestinal tract outside the classically described gastroesophageal location. Like esophageal variceal hemorrhage, bleeding from ectopic varices can be life-threatening. Diagnosis and treatment of ectopic varices can be challenging; to date, no effective treatment algorithm has been described. A systematic teamwork approach to diagnosing and treatment of ectopic varices is required to successfully manage hemorrhage from ectopic varices., (Copyright © 2017 Elsevier Inc. All rights reserved.)
Published: 2017
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267. Using fetal tissue.

Author: McFadden RA
Subjects: Humans, Brain Tissue Transplantation, Fetal Tissue Transplantation, Parkinson Disease surgery
Published: 1992

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267 results on '"McFadden, R. A."'

251. LOFAR discovery of a quiet emission mode in PSR B0823+26

252. LOFAR imaging of Cygnus A - direct detection of a turnover in the hotspot radio spectra

253. Wide-band, low-frequency pulse profiles of 100 radio pulsars with LOFAR

254. LBCS: The LOFAR Long-Baseline Calibrator Survey

255. LOFAR MSSS: detection of a low-frequency radio transient in 400 h of monitoring of the North Celestial Pole

256. Imaging Jupiter's radiation belts down to 127 MHz with LOFAR

257. The LOFAR Multifrequency Snapshot Sky Survey (MSSS): I. Survey description and first results

258. Lunar occultation of the diffuse radio sky: LOFAR measurements between 35 and 80 MHz

259. Probing Atmospheric Electric Fields in Thunderstorms through Radio Emission from Cosmic-Ray-Induced Air Showers

260. The shape of the radio wavefront of extensive air showers as measured with LOFAR

261. The LOFAR pilot surveys for pulsars and fast radio transients

262. The role of NYMEX in oil price risk management

263. Wide-field LOFAR imaging of the field around the double-double radio galaxy B1834+620

264. Nymex activity keeps growing

265. Detecting ultra high energy neutrinos with LOFAR

266. Treatment of Refractory Gastrointestinal Bleeding in Patients With Portal Hypertension: A Case Series and Treatment Algorithm.

267. Using fetal tissue.

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267 results on '"McFadden, R. A."'

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