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25 results on '"Departamento de Física y Astronomía"'

1. Microlensing of quasar ultraviolet iron emission

Author: Rojas, K. [Departamento de Física y Astronomía, Universidad de Valparaíso, Avda. Gran Bretaña 1111, Valparaíso (Chile)]
Published: 2013
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2. The Pristine Inner Galaxy Survey (PIGS) II: Uncovering the most metal-poor populations in the inner Milky Way

Author: Geraint F. Lewis, Jeffrey D. Simpson, Nicolas F. Martin, Zhen Wan, David Aguado, Kim A. Venn, Daniel B. Zucker, Anke Arentsen, Carlos Allende Prieto, Lyudmila Mashonkina, Rubén Sánchez-Janssen, Jonay I. González Hernández, Else Starkenburg, J. E. O'Connell, Julio F. Navarro, K. Youakim, Roger E. Cohen, Guillaume F. Thomas, Doug Geisler, Raymond G. Carlberg, Mathias Schultheis, Vanessa Hill, Leibniz Institute for Astrophysics Potsdam (AIP), Observatoire astronomique de Strasbourg (ObAS), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institute of Astronomy, University of Cambridge, Universidad de La Laguna [Tenerife - SP] (ULL), Joseph Louis LAGRANGE (LAGRANGE), Centre National de la Recherche Scientifique (CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA), University of British Columbia (UBC), Department of Astronomy and Astrophysics [Universty of Toronto], University of Toronto, Leibniz-Institut für Astrophysik Potsdam (AIP), Institute of Astronomy [Cambridge], University of Cambridge [UK] (CAM), Macquarie University, Instituto de Astrofisica de Canarias (IAC), Departamento de Astrofísica [La laguna], 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, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Department of Physics and Astronomy [Victoria], University of Victoria [Canada] (UVIC), Institute of Astronomy of the Russian Academy of Sciences (INASAN), Russian Academy of Sciences [Moscow] (RAS), UK Astronomy Technology Centre (UK ATC), Science and Technology Facilities Council (STFC), NRC Herzberg Astronomy and Astrophysics, Conseil National de Recherches Canada (CNRC), Sydney Institute for Astronomy (SIfA), The University of Sydney, School of Physics [UNSW Sydney] (UNSW), University of New South Wales [Sydney] (UNSW), Space Telescope Science Institute (STSci), Departamento de Astronomía [Concepción], Universidad de Concepción - University of Concepcion [Chile], Instituto de Investigación Multidisciplinario en Ciencia y Tecnología, Universidad de La Serena (USERENA), Departamento de Física y Astronomía [La Serena], Astronomy, and Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, Nice, France.
Subjects: Metallicity, Milky Way, FOS: Physical sciences, Astrophysics, 01 natural sciences, Galaxy: bulge, Photometry (optics), techniques: photometric, Bulge, 0103 physical sciences, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), ComputingMilieux_MISCELLANEOUS, Physics, Galaxy: stellar content, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Cosmic distance ladder, Astronomy and Astrophysics, stars: Population II, Horizontal branch, Astrophysics - Astrophysics of Galaxies, Galaxy, [SDU.ASTR.IM]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], Stars, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), [SDU.ASTR.GA]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Galactic Astrophysics [astro-ph.GA], stars: fundamental parameters, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], techniques: spectroscopic
Abstract: Metal-poor stars are important tools for tracing the early history of the Milky Way, and for learning about the first generations of stars. Simulations suggest that the oldest metal-poor stars are to be found in the inner Galaxy. Typical bulge surveys, however, lack low metallicity ([Fe/H] < -1.0) stars because the inner Galaxy is predominantly metal-rich. The aim of the Pristine Inner Galaxy Survey (PIGS) is to study the metal-poor and very metal-poor (VMP, [Fe/H] < -2.0) stars in this region. In PIGS, metal-poor targets for spectroscopic follow-up are selected from metallicity-sensitive CaHK photometry from the CFHT. This work presents the ~250 deg^2 photometric survey as well as intermediate-resolution spectroscopic follow-up observations for ~8000 stars using AAOmega on the AAT. The spectra are analysed using two independent tools: ULySS with an empirical spectral library, and FERRE with a library of synthetic spectra. The comparison between the two methods enables a robust determination of the stellar parameters and their uncertainties. We present a sample of 1300 VMP stars -- the largest sample of VMP stars in the inner Galaxy to date. Additionally, our spectroscopic dataset includes ~1700 horizontal branch stars, which are useful metal-poor standard candles. We furthermore show that PIGS photometry selects VMP stars with unprecedented efficiency: 86%/80% (lower/higher extinction) of the best candidates satisfy [Fe/H] < -2.0, as do 80%/63% of a larger, less strictly selected sample. We discuss future applications of this unique dataset that will further our understanding of the chemical and dynamical evolution of the innermost regions of our Galaxy., accepted for publication in MNRAS, 17 pages, 9 figures
Published: 2020
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3. VLT/SPHERE astrometric confirmation and orbital analysis of the brown dwarf companion HR 2562 B

Author: Anne-Lise Maire, Hervé Beust, Anne-Marie Lagrange, Daniel Rouan, D. Perret, Stéphane Udry, Miriam Keppler, S. Daemgen, Michael Meyer, M. Feldt, Arthur Vigan, D. Maurel, Thomas Henning, L. Rodet, R. G. Gratton, J. C. Augereau, Hubert Klahr, C. Petit, Johan Olofsson, A. Delboulbe, Philippe Thébault, Silvano Desidera, R. Ligi, Maud Langlois, Wolfgang Brandner, Faustine Cantalloube, Valentina D'Orazi, A. Roux, Mickael Bonnefoy, Jose Ramos, Thibaut Moulin, L. Abe, Janis Hagelberg, L. Weber, Dino Mesa, M. Carle, H. Le Coroller, Anthony Boccaletti, Matthias Samland, A. Zurlo, Raphaël Galicher, A. Pavlov, Philippe Feautrier, Markus Janson, T. Schmidt, Yves Magnard, C. Lazzoni, Gael Chauvin, F. Rigal, Max-Planck-Institut für Astronomie (MPIA), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, INAF - Osservatorio Astronomico di Padova (OAPD), Istituto Nazionale di Astrofisica (INAF), Dipartimento di Fisica e Astronomia G. Galilei, Università di Padova, 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), INCT, Universidad de Atacama, calle Copayapu 485, Copiapo, Atacama, Chile, Laboratoire Franco-Chilien d'Astronomie, UMI 3386, Department of Astronomy, Stockholm University, AlbaNova University Center, 106 91, Stockholm, Sweden, Departamento de Física y Astronomía, Universidad de Valparaiso, Institute for Astronomy, Department of Physics, ETH Zürich, 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), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), University of Michigan, INAF - Osservatorio Astronomico di Brera (OAB), ISDC, Geneva Observatory, University of Geneva, Nucleo de Astronomia, Facultad de Ingenieria, Universidad Diego Portales, Avenida Ejercito 441, Santiago, Chile, Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA), ONERA - The French Aerospace Lab [Palaiseau], ONERA-Université Paris Saclay (COmUE), Astronomical Institute Anton Pannekoek, University of Amsterdam, Max-Planck-Gesellschaft, Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Dipartimento di Fisica e Astronomia 'Galileo Galilei', Università degli Studi di Padova = University of Padua (Unipd), Instituto de Astronomia y ciencias Planetarias de Atacama (INCT), Universidad de Atacama, Laboratoire Franco-Chilien d'Astronomie (LFCA), Universidad de Chile = University of Chile [Santiago] (UCHILE)-Pontificia Universidad Católica de Chile (UC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Universidad de Concepción - University of Concepcion [Chile], Stockholm University, Universidad de Valparaiso [Chile], Institute of Astronomy [ETH Zürich], Department of Physics [ETH Zürich] (D-PHYS), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)- Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), University of Michigan [Ann Arbor], University of Michigan System, Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève = University of Geneva (UNIGE), Universidad Diego Portales [Santiago] (UDP), Universidad de Chile = University of Chile [Santiago] (UCHILE), Observatoire de la Côte d'Azur (OCA), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), DOTA, ONERA, Université Paris Saclay (COmUE) [Palaiseau], Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Universita degli Studi di Padova, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Universidad de Concepción [Chile]-Pontificia Universidad Católica de Chile (UC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Universidad de Chile, Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich)-Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Université de Genève (UNIGE), Universidad de Chile, Centre National de la Recherche Scientifique (CNRS), DOTA, ONERA, Université Paris Saclay [Palaiseau], ONERA-Université Paris-Saclay, Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), and Université Paris Saclay (COmUE)-ONERA
Subjects: 010504 meteorology & atmospheric sciences, BROWN DWARFS, Brown dwarf, FOS: Physical sciences, METHODS: DATA ANALYSIS, Astrophysics, 01 natural sciences, [SPI]Engineering Sciences [physics], 0103 physical sciences, TECHNIQUES: IMAGE PROCESSING, Coordination network, Astrophysics::Solar and Stellar Astrophysics, European commission, STARS: INDIVIDUAL: HR 2562, 010303 astronomy & astrophysics, Orbital analysis, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, Earth and Planetary Astrophysics (astro-ph.EP), Physics, [PHYS]Physics [physics], Astronomy and Astrophysics, PLANETS AND SATELLITES: DYNAMICAL EVOLUTION AND STABILITY, Space and Planetary Science, Astrophysics::Earth and Planetary Astrophysics, TECHNIQUES: HIGH ANGULAR RESOLUTION, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - Earth and Planetary Astrophysics
Abstract: Context. A low-mass brown dwarf has been recently imaged around HR 2562 (HD 50571), a star hosting a debris disk resolved in the far infrared. Interestingly, the companion location is compatible with an orbit coplanar with the disk and interior to the debris belt. This feature makes the system a valuable laboratory to analyze the formation of substellar companions in a circumstellar disk and potential disk-companion dynamical interactions. Aims. We aim to further characterize the orbital motion of HR 2562 B and its interactions with the host star debris disk. Methods. We performed a monitoring of the system over ~10 months in 2016 and 2017 with the VLT/SPHERE exoplanet imager. Results. We confirm that the companion is comoving with the star and detect for the first time an orbital motion at high significance, with a current orbital motion projected in the plane of the sky of 25 mas (~0.85 au) per year. No orbital curvature is seen in the measurements. An orbital fit of the SPHERE and literature astrometry of the companion without priors on the orbital plane clearly indicates that its orbit is (quasi-)coplanar with the disk. To further constrain the other orbital parameters, we used empirical laws for a companion chaotic zone validated by N-body simulations to test the orbital solutions that are compatible with the estimated disk cavity size. Non-zero eccentricities (>0.15) are allowed for orbital periods shorter than 100 yr, while only moderate eccentricities up to ~0.3 for orbital periods longer than 200 yr are compatible with the disk observations. A comparison of synthetic Herschel images to the real data does not allow us to constrain the upper eccentricity of the companion., Accepted for publication in A&A. 14 pages, 14 figures, 3 tables. Updated to match published paper. Bug in the computation of the distributions of times at periastron passages corrected, minor effects on other orbital parameters
Published: 2018
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4. New constraints on the disk characteristics and companion candidates around T Chamaeleontis with VLT/SPHERE

Author: Th. Henning, E. Sissa, R. van Boekel, André Müller, Silvano Desidera, C. Perrot, Anne-Marie Lagrange, Anne-Lise Maire, Sebastian Daemgen, Johan Olofsson, Alice Zurlo, Gael Chauvin, Antonio Garufi, Beth Biller, Ch. Ginski, R. G. van Holstein, Dino Mesa, Arthur Vigan, R. G. Gratton, Maud Langlois, Tomas Stolker, M. Cudel, Myriam Benisty, Francois Menard, Judit Szulágyi, M. Kasper, J. de Boer, Carsten Dominik, Francois Wildi, Markus Janson, Anthony Cheetham, Christophe Pinte, Quentin Kral, M. Feldt, Anthony Boccaletti, A. Pohl, Mickael Bonnefoy, Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), 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-16-CE31-0013,PLANET-FORMING-DISKS,De meilleurs modèles pour de meilleures données(2016), Max-Planck-Institut für Astronomie (MPIA), INAF-Osservatorio Astronomico di Padova, 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), Leiden Observatory, Departamento de Física y Astronomía, Universidad de Valparaiso, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, Institute for Astronomy, Department of Physics, ETH Zürich, Astronomical Institute Anton Pannekoek, University of Amsterdam, Institute of Astronomy, University of Cambridge (IoA), Nucleo de Astronomia, Facultad de Ingenieria, Universidad Diego Portales, Av. Ejercito 441, Santiago, Chile, Observatoire astronomique de l'Universite de Geneve, 51 ch. des Maillettes, 1290, Versoix, Switzerland, European Southern Observatory (ESO), and Low Energy Astrophysics (API, FNWI)
Subjects: Physics, Earth and Planetary Astrophysics (astro-ph.EP), [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Astronomy, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, 01 natural sciences, 010309 optics, 13. Climate action, Space and Planetary Science, 0103 physical sciences, Coordination network, Astrophysics::Solar and Stellar Astrophysics, Christian ministry, European commission, Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Astrophysics - Earth and Planetary Astrophysics
Abstract: The transition disk around the T Tauri star T Cha possesses a large gap, making it a prime target for high-resolution imaging in the context of planet formation. We aim to find signs of disk evolutionary processes by studying the disk geometry and the dust grain properties at its surface, and to search for companion candidates. We analyze a set of VLT/SPHERE data at near-infrared and optical wavelengths. We performed polarimetric imaging of T Cha with IRDIS (1.6 $\mu$m) and ZIMPOL (0.5-0.9 $\mu$m), and obtained intensity images from IRDIS dual-band imaging with simultaneous spectro-imaging with IFS (0.9-1.3 $\mu$m). The disk around T Cha is detected in all observing modes and its outer disk is resolved in scattered light with unprecedented angular resolution and signal-to-noise. The images reveal a highly inclined disk with a noticeable east-west brightness asymmetry. The significant amount of non-azimuthal polarization signal in the $U_{\phi}$ images, with a $U_{\phi}$/$Q_{\phi}$ peak-to-peak value of 14%, is in accordance with theoretical studies on multiple scattering. Our optimal axisymmetric radiative transfer model considers two coplanar inner and outer disks, separated by a gap of 0.28" (~30au) in size. We derive a disk inclination of ~69 deg and PA of ~114 deg. In order to self-consistently reproduce the intensity and polarimetric images, the dust grains, responsible for the scattered light, need to be dominated by sizes of around ten microns. A point source is detected at an angular distance of 3.5" from the central star. It is, however, found not to be co-moving. We confirm that the dominant source of emission is forward scattered light from the near edge of the outer disk. Our point source analysis rules out the presence of a companion heavier than ~8.5 $M_{\mathrm{jup}}$ between 0.1" and 0.3". The detection limit decreases to ~2 $M_{\mathrm{jup}}$ for 0.3" to 4.0"., Comment: 17 pages, 14 figures, accepted for publication in A&A. Revised version after language editing
Published: 2017
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5. INFRARED COLOR SELECTION OF MASSIVE GALAXIES AT z \textgreater 3

Author: Wang, T., Elbaz, D., Schreiber, C., Pannella, M., Shu, X., Willner, S. P., Ashby, M. L. N., Huang, J. -S., Fontana, A., Dekel, A., Daddi, Emanuele, Ferguson, H. C., Dunlop, J., Ciesla, L., Koekemoer, A. M., Giavalisco, M., Boutsia, K., Finkelstein, S., Juneau, S., Barro, G., Koo, D. C., Michalowski, M. J., Orellana, G., Lu, Y., Castellano, M., Bourne, N., Buitrago, F., Santini, P., Faber, S. M., Hathi, N., Lucas, R. A., Pérez-González, P. G., 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), Institut d'Astrophysique de Paris (IAP), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University [Cambridge]-Smithsonian Institution, INAF - Osservatorio Astronomico di Roma (OAR), Istituto Nazionale di Astrofisica (INAF), Racah Institute of Physics, The Hebrew University of Jerusalem (HUJ), SUPA, Institute for Astronomy, University of Edinburgh, Institute for Space Applications and Remote Sensing (ISARS/NOA), National Observatory of Athens (NOA), University of Crete [Heraklion] (UOC), Space Telescope Science Institute (STSci), Department of Astronomy [Amherst], University of Massachusetts [Amherst] (UMass Amherst), University of Massachusetts System (UMASS)-University of Massachusetts System (UMASS), Laboratoire de Probabilités et Modèles Aléatoires (LPMA), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université Pierre et Marie Curie - Paris 6 (UPMC), AUTRES, UCO/Lick Observatory, University of California [Santa Cruz] (UCSC), University of California-University of California, Laboratoire d'Astrophysique de Marseille (LAM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Departamento de Física y Astronomía, Universidad Complutense de Madrid = Complutense University of Madrid [Madrid] (UCM), 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 Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Harvard University-Smithsonian Institution, Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), University of California [Santa Cruz] (UC Santa Cruz), University of California (UC)-University of California (UC), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), National Observatory of Athens, Institute for Space Applications and Remote Sensing, and Universidad Complutense de Madrid [Madrid] (UCM)
Subjects: [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: International audience; We introduce a new color selection technique to identify high-redshift, massive galaxies that are systematically missed by Lyman-break selection. The new selection is based on the H-160 (H) and Infrared Array Camera (IRAC) 4.5 mu m bands, specifically H - [4.5] \textgreater 2.25 mag. These galaxies, called “HIEROs,” include two major populations that can be separated with an additional J - H color. The populations are massive and dusty starforming galaxies at z \textgreater 3 (JH - blue) and extremely dusty galaxies at z less than or similar to 3 (JH - red). The 350 arcmin(2) of the GOODS-North and GOODS-South fields with the deepest Hubble Space Telescope (HST)/Wide Field Camera 3 (WFC3) near-infrared and IRAC data contain as many as 285 HIEROs down to [4.5] \textless 24 mag. Inclusion of the most extreme HIEROs, not even detected in the H band, makes this selection particularly complete for the identification of massive high-redshift galaxies. We focus here primarily on JH - blue (z \textgreater 3) HIEROs, which have a median photometric redshift \textless z \textgreater similar to 4.4 and stellar mass M-* 10(10.6) M-circle dot and are much fainter in the rest-frame UV than similarly massive Lyman-break galaxies (LBGs). Their star formation rates (SFRs), derived from their stacked infrared spectral energy distributions (SEDs), reach similar to 240 M-circle dot yr(-1), leading to a specific SFR, sSFR equivalent to SFR/M-* similar to 4.2 Gyr(-1), suggesting that the sSFRs for massive galaxies continue to grow at z \textgreater 2 but at a lower growth rate than from z = 0 to z = 2. With a median half-light radius of 2 kpc, including similar to 20% as compact as quiescent (QS) galaxies at similar redshifts, JH - blue HIEROs represent perfect star-forming progenitors of the most massive (M-* greater than or similar to 10(11.2) M-circle dot) compact QS galaxies at z similar to 3 and have the right number density. HIEROs make up similar to 60% of all galaxies with M-* \textgreater 10(10.5) M-circle dot identified at z \textgreater 3 from their photometric redshifts. This is five times more than LBGs with nearly no overlap between the two populations. While HIEROs make up 15%-25% of the total SFR density at z similar to 4-5, they completely dominate the SFR density taking place in M-* 10(10.5) M-circle dot galaxies, and HIEROs are therefore crucial to understanding the very early phase of massive galaxy formation.
Published: 2016
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6. [C II] and ^(12)CO(1-0) Emission Maps in HLSJ091828.6+514223: A Strongly Lensed Interacting System at z=5.24

Author: Ian Smail, J. P. Kneib, Giovanni G. Fazio, Andrew Blain, I. Valtchanov, Frédéric Boone, R. S. Bussmann, A. L. R. Danielson, Rob Ivison, P. van der Werf, Johan Richard, Gregory Walth, Miroslava Dessauges-Zavadsky, M. Rex, T. A. Jones, Daniel Schaerer, A. M. Swinbank, Michael Zemcov, Bruno Altieri, M. Zamojski, Pablo G. Pérez-González, Francoise Combes, Mark Gurwell, Eiichi Egami, T. D. Rawle, A. C. Edge, Benjamin Clément, Alain Omont, Steward Observatory, University of Arizona, AUTRES, Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University [Cambridge]-Smithsonian Institution, Royal Observatory Edinburgh (ROE), University of Edinburgh, Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung (AWI), 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), Institute for Computational Cosmology (ICC), Durham University, Department of Physics, Herschel Science Centre, European Space Agency (ESA), Department of Physics and Astronomy [Leicester], University of Leicester, Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève (UNIGE), Laboratoire d'Astrophysique de Marseille (LAM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Institut d'Astrophysique de Paris (IAP), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Departamento de Física y Astronomía, Universidad Complutense de Madrid = Complutense University of Madrid [Madrid] (UCM), Institut de recherche en astrophysique et planétologie (IRAP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), California Institute of Technology (CALTECH), Harvard University-Smithsonian Institution, 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), Agence Spatiale Européenne = European Space Agency (ESA), Université de Genève = University of Geneva (UNIGE), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), 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), and 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)
Subjects: Astrofísica, submillimeter: galaxies, Cosmology and Nongalactic Astrophysics (astro-ph.CO), [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Continuum (design consultancy), FOS: Physical sciences, Astrophysics, Submillimeter Array, star formation [Galaxies], Spectral line, Luminosity, high-redshift [Galaxies], [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], galaxies: high-redshift, Physics, galaxies. [Submillimeter], Star formation, Astronomy and Astrophysics, Galaxy, Interstellar medium, Astronomía, Stars, 13. Climate action, Space and Planetary Science, galaxies: star formation, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: We present Submillimeter Array (SMA) [CII] 158um and Jansky Very Large Array (JVLA) $^{12}$CO(1-0) line emission maps for the bright, lensed, submillimeter source at $z=5.2430$ behind Abell 773: HLSJ091828.6+514223 (HLS0918). We combine these measurements with previously reported line profiles, including multiple $^{12}$CO rotational transitions, [CI], water and [NII], providing some of the best constraints on the properties of the interstellar medium (ISM) in a galaxy at $z>5$. HLS0918 has a total far-infrared (FIR) luminosity L_FIR(8-1000um) = (1.6$\pm$0.1)x10^14 L_sun/mu, where the total magnification mu_total = 8.9$\pm$1.9, via a new lens model from the [CII] and continuum maps. Despite a HyLIRG luminosity, the FIR continuum shape resembles that of a local LIRG. We simultaneously fit all of the observed spectral line profiles, finding four components which correspond cleanly to discrete spatial structures identified in the maps. The two most redshifted spectral components occupy the nucleus of a massive galaxy, with a source plane separation, 28 pages, 9 figures, accepted in ApJ
Published: 2014
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7. An extended Herschel drop-out source in the center of AS1063: a normal dusty galaxy at z = 6.1 or SZ substructures?

Author: Frédéric Boone, Ivan Valtchanov, Alain Omont, D. Schaerer, Kirsten Kraiberg Knudsen, Timothy D. Rawle, Dieter Lutz, Miroslava Dessauges-Zavadsky, Gregory Walth, Ian Smail, Eiichi Egami, Michael Zemcov, P. van der Werf, Andrew Blain, Rob Ivison, Benjamin Clément, Francoise Combes, Scott Chapman, R. Pello, Bruno Altieri, A. M. Swinbank, Pablo G. Pérez-González, A. Weiß, Jean-Paul Kneib, Johan Richard, M. Zamojski, AUTRES, Steward Observatory, University of Arizona, 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), 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), Max-Planck-Institut für Extraterrestrische Physik (MPE), California Institute of Technology (CALTECH), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-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 de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Institute for Computational Cosmology (ICC), Durham University, Department of Physics, Herschel Science Centre, Agence Spatiale Européenne = European Space Agency (ESA), Department of Physics and Astronomy [Leicester], University of Leicester, Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève = University of Geneva (UNIGE), Royal Observatory Edinburgh (ROE), University of Edinburgh, Institut d'Astrophysique de Paris (IAP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Departamento de Física y Astronomía, Universidad Complutense de Madrid = Complutense University of Madrid [Madrid] (UCM), Leiden Observatory [Leiden], Universiteit 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), 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), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), École normale supérieure - Paris (ENS Paris), European Space Agency (ESA), Université de Genève (UNIGE), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), and Universiteit Leiden [Leiden]
Subjects: Astrofísica, submillimeter: galaxies, Cosmology and Nongalactic Astrophysics (astro-ph.CO), [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], High-redshift, FOS: Physical sciences, Astrophysics, star formation [Galaxies], 01 natural sciences, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Far infrared, galaxies: high-redshift, Drop out, 0103 physical sciences, Brightest cluster galaxy, Formation rate, 010303 astronomy & astrophysics, Reionization, galaxies. [Submillimeter], Physics, 010308 nuclear & particles physics, Astronomy and Astrophysics, evolution [Galaxies], Redshift, Galaxy, Astronomía, Space and Planetary Science, galaxies: star formation, Substructure, galaxies: evolution, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: In the course of our 870um APEX/LABOCA follow up of the Herschel Lensing Survey we have detected a source in AS1063 (RXC J2248.7-4431), that has no counterparts in any of the Herschel PACS/SPIRE bands, it is a Herschel 'drop-out' with S_870/S_500>0.5. The 870um emission is extended and centered on the brightest cluster galaxy suggesting either a multiply imaged background source or substructure in the Sunyaev-Zel'dovich (SZ) increment due to inhomogeneities in the hot cluster gas of this merging cluster. We discuss both interpretations with emphasis on the putative lensed source. Based on the observed properties and on our lens model we find that this source could be the first SMG with a moderate far infrared luminosity (L_FIR4. In deep HST observations we identified a multiply imaged z~6 source and we measured its spectroscopic redshift z=6.107 with VLT/FORS. This source could be associated with the putative SMG but it is most likely offset spatially by 10-30kpc and they could be interacting galaxies. With a FIR luminosity in the range [5-15]x10^{11} L_sol corresponding to a star formation rate in the range [80-260]M_sol/yr, this SMG would be more representative than the extreme starbursts usually detected at z>4. With a total magnification of ~25 it would open a unique window to the 'normal' dusty galaxies at the end of the epoch of reionization., accepted for publication in A&A
Published: 2013
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8. A bright z = 5.2 lensed submillimeter galaxy in the field of Abell 773. HLSJ091828.6+514223

Author: Alastair C. Edge, Mark Gurwell, Daniel Schaerer, A. Berciano Alba, François Combes, Alain Omont, Marie Rex, Graham P. Smith, Ian Smail, P. van der Werf, Caitlin M. Casey, Nobuhiro Okabe, Frédéric Boone, Eiichi Egami, T. D. Rawle, Giovanni G. Fazio, R. Pello, Rob Ivison, Johan Richard, Miroslava Dessauges-Zavadsky, J. P. Kneib, A. M. Swinbank, Pablo G. Pérez-González, Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-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 de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung (AWI), Steward Observatory, University of Arizona, 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), Institute for Computational Cosmology (ICC), Durham University, 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), Royal Observatory Edinburgh (ROE), University of Edinburgh, Centre for Astronomy, Harvard University, IOA, University of Hawai‘i [Mānoa] (UHM), Institut d'Astrophysique de Paris (IAP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Netherlands Institute for Radio Astronomy (ASTRON), Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève = University of Geneva (UNIGE), Department of Physics, Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University-Smithsonian Institution, Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Astronomical institute, Tohoku University, Tohoku University [Sendai], Departamento de Física y Astronomía, Universidad Complutense de Madrid = Complutense University of Madrid [Madrid] (UCM), University of Reading (UOR), Leiden Observatory [Leiden], Universiteit Leiden, Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), 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)-Université Fédérale Toulouse Midi-Pyrénées-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), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Harvard University [Cambridge], Université de Genève (UNIGE), Harvard University [Cambridge]-Smithsonian Institution, Universiteit Leiden [Leiden], École normale supérieure - Paris (ENS Paris), 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), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), and Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES)
Subjects: Astrofísica, submillimeter: galaxies, Cosmology and Nongalactic Astrophysics (astro-ph.CO), Active galactic nucleus, Evolution, [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], High-redshift, FOS: Physical sciences, Astrophysics, 01 natural sciences, Luminosity, infrared: galaxies, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], galaxies: high-redshift, 0103 physical sciences, Galaxy formation and evolution, Submillimeter, HLSJ091828.6+514223, 010303 astronomy & astrophysics, ISM, Galaxy cluster, Line (formation), Physics, Luminous infrared galaxy, 010308 nuclear & particles physics, Astronomy and Astrophysics, Galaxies, galaxies: individual: HLSJ091828.6+514223, Galaxy, Redshift, Astronomía, Space and Planetary Science, infrared, galaxies: evolution, galaxies: ISM, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: During our Herschel Lensing Survey (HLS) of massive galaxy clusters, we have discovered an exceptionally bright source behind the z=0.22 cluster Abell 773, which appears to be a strongly lensed submillimeter galaxy (SMG) at z=5.2429. This source is unusual compared to most other lensed sources discovered by Herschel so far, because of its higher submm flux (\sim 200mJy at 500\micron) and its high redshift. The dominant lens is a foreground z=0.63 galaxy, not the cluster itself. The source has a far-infrared (FIR) luminosity of L_FIR= 1.1 10^{14}/\mu Lo, where \mu is the magnification factor, likely \sim 11. We report here the redshift identification through CO lines with the IRAM-30m, and the analysis of the gas excitation, based on CO(7-6), CO(6-5), CO(5-4) detected at IRAM and the CO(2-1) at the EVLA. All lines decompose into a wide and strong red component, and a narrower and weaker blue component, 540\kms apart. Assuming the ultraluminous galaxy (ULIRG) CO-to-H2 conversion ratio, the H2 mass is 5.8 10^{11}/\mu Mo, of which one third is in a cool component. From the CI line we derive a CI/H2 number abundance of 6 10^{-5} similar to that in other ULIRGs. The H2O line is strong only in the red velocity component, with an intensity ratio I(H_2O)/I(CO) \sim 0.5, suggesting a strong local FIR radiation field, possibly from an active nucleus (AGN) component. We detect the [NII]205\mics line for the first time at high-z. It shows comparable blue and red components, with a strikingly broad blue one, suggesting strong ionized gas flows., Comment: 5 pages, 4 figures, to be published in A and A Letters
Published: 2012
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9. Improving the identification of high-z Herschel sources with position priors and optical/NIR and FIR/mm photometric redshifts

Author: Douglas Clowe, Johan Richard, Bruno Altieri, Jean-Paul Kneib, Olivier Ilbert, Benjamin Clément, Eiichi Egami, Néstor Espino-Briones, Giulia Rodighiero, Dario Fadda, Anthony H. Gonzalez, Michael W. Werner, Miroslava Dessauges-Zavadsky, J. G. Cuby, T. D. Rawle, Mathilde Jauzac, Michael Zemcov, Francoise Combes, George H. Rieke, Daniel Johansson, Sun Mi Chung, Andrew Blain, James J. Bock, M. J. Pereira, Marie Rex, Ivan Valtchanov, Frédéric Boone, Graham P. Smith, P. van der Werf, Daniel Schaerer, Gregory Walth, A. K. Fiedler, C. D. Dowell, Carrie Bridge, R. Pello, Rob Ivison, Cathy Horellou, Pablo G. Pérez-González, Dieter Lutz, Departamento de Física y Astronomía, Universidad Complutense de Madrid = Complutense University of Madrid [Madrid] (UCM), Steward Observatory, University of Arizona, Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung (AWI), Laboratoire d'Astrophysique de Marseille (LAM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), 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), AUTRES, XMM-Newton Science Operations Centre, European Space Agency (ESA), Department of Astronomy, California Institute of Technology (CALTECH), Institut de recherche en astrophysique et planétologie (IRAP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-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 de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève (UNIGE), Department of Astronomy [Gainesville] (UF|Astro), University of Florida [Gainesville] (UF), Royal Observatory Edinburgh (ROE), University of Edinburgh, Max-Planck-Institut für Extraterrestrische Physik (MPE), University of Alabama at Birmingham [ Birmingham] (UAB), Leiden Observatory [Leiden], Universiteit Leiden [Leiden], Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), 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), Agence Spatiale Européenne = European Space Agency (ESA), 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), École normale supérieure - Paris (ENS-PSL), Université de Genève = University of Geneva (UNIGE), and Universiteit Leiden
Subjects: Astrofísica, submillimeter: galaxies, Cosmology and Nongalactic Astrophysics (astro-ph.CO), Stellar population, [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Noise (electronics), infrared: galaxies, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], galaxies: high-redshift, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Galaxy Astrophysics, Photometric redshift, Physics, Astrophysics::Instrumentation and Methods for Astrophysics, Spectral density, gravitational lensing: strong, Astronomy and Astrophysics, Galaxy, Redshift, Astronomía, Spire, galaxies: photometry, Space and Planetary Science, Millimeter, Astrophysics::Earth and Planetary Astrophysics, galaxies: evolution, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: We present preliminary results about the detection of high redshift (U)LIRGs in the Bullet cluster field by the PACS and SPIRE instruments within the Herschel Lensing Survey (HLS) Program. We describe in detail a photometric procedure designed to recover robust fluxes and deblend faint Herschel sources near the confusion noise. The method is based on the use of the positions of Spitzer/MIPS 24 um sources as priors. Our catalogs are able to reliably (5 sigma) recover galaxies with fluxes above 6 and 10 mJy in the PACS 100 and 160 um channels, respectively, and 12 to 18 mJy in the SPIRE bands. We also obtain spectral energy distributions covering the optical through the far-infrared/millimeter spectral ranges of all the Herschel detected sources, and analyze them to obtain independent estimations of the photometric redshift based on either stellar population or dust emission models. We exemplify the potential of the combined use of Spitzer position priors plus independent optical and IR photometric redshifts to robustly assign optical/NIR counterparts to the sources detected by Herschel and other (sub-)mm instruments., Accepted for publication in Astronomy and Astrophysics (Herschel special issue)
Published: 2010
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10. Mid-infrared spectroscopy of lensed galaxies at 1 < z < 3: The nature of sources near the MIPS confusion limit

Author: Eiichi Egami, Kirsten Kraiberg Knudsen, Jane R. Rigby, P. van der Werf, Dario Fadda, Christopher N. A. Willmer, C. Borys, Jean-Paul Kneib, C. Papovich, Delphine Marcillac, Johan Richard, George H. Rieke, Pablo G. Pérez-González, Steward Observatory, University of Arizona, Department of Astronomy [Pasadena], California Institute of Technology (CALTECH), Laboratoire d'Astrophysique de Marseille (LAM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), AUTRES, Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Departamento de Física y Astronomía, Universidad Complutense de Madrid = Complutense University of Madrid [Madrid] (UCM), and Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Astrofísica, 010504 meteorology & atmospheric sciences, [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Infrared, Metallicity, Astrophysics::High Energy Astrophysical Phenomena, Flux, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Spectral line, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Galaxies: Evolution, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, Physics, Astronomy and Astrophysics, Galaxies: High-Redshift, Redshift, Accretion (astrophysics), Galaxy, Astronomía, Infrared: Galaxies, Wavelength, Space and Planetary Science, Astrophysics::Earth and Planetary Astrophysics
Abstract: We present Spitzer/IRS mid-infrared spectra for 15 gravitationally lensed, 24 micron--selected galaxies, and combine the results with 4 additional very faint galaxies with IRS spectra in the literature. The median intrinsic 24 micron flux density of the sample is 130 microJy, enabling a systematic survey of the spectral properties of the very faint 24 micron sources that dominate the number counts of Spitzer cosmological surveys. Six of the 19 galaxy spectra (32%) show the strong mid-IR continuua expected of AGN; X-ray detections confirm the presence of AGN in three of these cases, and reveal AGNs in two other galaxies. These results suggest that nuclear accretion may contribute more flux to faint 24 micron--selected samples than previously assumed. Almost all the spectra show some aromatic (PAH) emission features; the measured aromatic flux ratios do not show evolution from z=0. In particular, the high S/N mid-IR spectrum of SMM J163554.2+661225 agrees remarkably well with low--redshift, lower--luminosity templates. We compare the rest-frame 8 micron and total infrared luminosities of star--forming galaxies, and find that the behavior of this ratio with total IR luminosity has evolved modestly from z=2 to z=0. Since the high aromatic--to--continuum flux ratios in these galaxies rule out a dominant contribution by AGN, this finding implies systematic evolution in the structure and/or metallicity of infrared sources with redshift. It also has implications for the estimates of star forming rates inferred from 24 micron measurements, in the sense that at z ~2, a given observed frame 24 micron luminosity corresponds to a lower bolometric luminosity than would be inferred from low-redshift templates of similar luminosity at the corresponding rest wavelength., Comment: Accepted to the Astrophysical Journal. Full-res version at ftp://ftp.ociw.edu/pub/jrigby/jrigby-irs.pdf
Published: 2008
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11. Spitzer and Hubble Space Telescope Constraints on the Physical Properties of the z~7 Galaxy Strongly Lensed by A2218

Author: J. S. Huang, Daniel P. Stark, E. Le Floc'h, Jane R. Rigby, C. Papovich, Herve Dole, Johan Richard, Richard S. Ellis, Michael R. Santos, Eiichi Egami, Pablo G. Pérez-González, George H. Rieke, Jean-Paul Kneib, Steward Observatory, University of Arizona, Laboratoire d'Astrophysique de Marseille (LAM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), California Institute of Technology (CALTECH), Laboratoire Astrophysique de Toulouse-Tarbes (LATT), Centre National de la Recherche Scientifique (CNRS)-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)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, AUTRES, Departamento de Física y Astronomía, Universidad Complutense de Madrid = Complutense University of Madrid [Madrid] (UCM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), 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), and 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)
Subjects: 010504 meteorology & atmospheric sciences, Stellar mass, Stellar population, Cosmology: Gravitational Lensing, [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Cosmology: Observations, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], 0103 physical sciences, Galaxies: Evolution, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, Galaxy cluster, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, Photometric redshift, Physics, Star formation, Galaxies: Formation, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy and Astrophysics, Galaxies: High-Redshift, Galaxy, Redshift, Space and Planetary Science, Spectral energy distribution, Astrophysics::Earth and Planetary Astrophysics
Abstract: International audience; We report the detection of a z~7 galaxy strongly lensed by the massive galaxy cluster A2218 (z=0.175) at 3.6 and 4.5 μm using the Spitzer Space Telescope and at 1.1 μm using the Hubble Space Telescope. The new data indicate a refined photometric redshift in the range of 6.6-6.8 depending on the presence of Lyα emission. The spectral energy distribution is consistent with having a significant Balmer break, suggesting that the galaxy is in the poststarburst stage with an age of at least ~50 Myr and quite possibly a few hundred million years. This suggests the possibility that a mature stellar population is already in place at such a high redshift. Compared with typical Lyman break galaxies at z~3-4, the stellar mass is an order of magnitude smaller (~109 Msolar), but the specific star formation rate (star formation rate/Mstar) is similarly large (>10-9 yr-1), indicating equally vigorous star-forming activity. This work is based in part on observations made with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under NASA contract 1407. Support for this work was provided by NASA through contract 960785 issued by JPL/Caltech. This work is also based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with program 9452.
Published: 2005
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12. A magnetic massive star has experienced a stellar merger.

Author: Frost AJ, Sana H, Mahy L, Wade G, Barron J, Le Bouquin JB, Mérand A, Schneider FRN, Shenar T, Barbá RH, Bowman DM, Fabry M, Farhang A, Marchant P, Morrell NI, and Smoker JV
Abstract: Massive stars (those ≥8 solar masses at formation) have radiative envelopes that cannot sustain a dynamo, the mechanism that produces magnetic fields in lower-mass stars. Despite this, approximately 7% of massive stars have observed magnetic fields, the origin of which is debated. We used multi-epoch interferometric and spectroscopic observations to characterize HD 148937, a binary system of two massive stars. We found that only one star is magnetic and that it appears younger than its companion. The system properties and a surrounding bipolar nebula can be reproduced with a model in which two stars merged (in a previous triple system) to produce the magnetic massive star. Our results provide observational evidence that magnetic fields form in at least some massive stars through stellar mergers.
Published: 2024
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13. Response to Comment on "An excess of massive stars in the local 30 Doradus starburst".

Author: Schneider FRN, Sana H, Evans CJ, Bestenlehner JM, Castro N, Fossati L, Gräfener G, Langer N, Ramírez-Agudelo OH, Sabín-Sanjulián C, Simón-Díaz S, Tramper F, Crowther PA, de Koter A, de Mink SE, Dufton PL, Garcia M, Gieles M, Hénault-Brunet V, Herrero A, Izzard RG, Kalari V, Lennon DJ, Maíz Apellániz J, Markova N, Najarro F, Podsiadlowski P, Puls J, Taylor WD, van Loon JT, Vink JS, and Norman C
Subjects: Time, Extraterrestrial Environment, Stars, Celestial
Abstract: Farr and Mandel reanalyze our data, finding initial mass function slopes for high-mass stars in 30 Doradus that agree with our results. However, their reanalysis appears to underpredict the observed number of massive stars. Their technique results in more precise slopes than in our work, strengthening our conclusion that there is an excess of massive stars (>30 solar masses) in 30 Doradus., (Copyright © 2018, American Association for the Advancement of Science.)
Published: 2018
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14. Investigation of EBT3 radiochromic film's response to humidity.

Author: León-Marroquín EY, Lárraga-Gutiérrez JM, Herrera-González JA, Camacho-López MA, Villarreal Barajas JE, and García-Garduño OA
Subjects: Humans, Immersion, Radiation Dosage, Uncertainty, Calibration, Film Dosimetry instrumentation, Film Dosimetry methods, Humidity, Water chemistry
Abstract: Purpose: The aim of this work is to investigate the effects of immersing EBT3 radiochromic film in water and to evaluate its contribution to the total uncertainty in dose determination., Materials and Methods: We used 3 cm × 3 cm EBT3 radiochromic films irradiated in the range of 0-70 Gy to study the impact of water immersion on the change in net optical density. These films were placed in a water container for a period of 24 h. The net optical density was measured before (0 h) and after of the immersion in water (1, 3, 6, 12, 18, and 24 h). The absorbance spectrum of the EBT3 radiochromic film was measured at 0 h and 24 h after immersion in water. The uncertainty in dose determination due to the effects of keeping the EBT3 radiochromic film submerged in water at 0, 1, and 24 h were recorded in the red, green, and blue channels., Results: We observed an increase in the net optical density as an effect on the film due to its immersion in water. The penetration of the water at the edges of the radiochromic film was observed to be a function of time during which the film remained in the water. On the other hand, the penetration of water at the edges of the film was found to be independent of irradiation dose., Conclusions: EBT3 radiochromic film is found more resistant to water penetration through the edges than its predecessors. However, there is evidence that suggest that liquid water damage the Nylon cover layer of the film by changing its optical properties. Therefore, it is recommended to build a new calibration curve for radiochromic films for a specific situation involving dose measurements in liquid water., (© 2018 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.)
Published: 2018
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15. An excess of massive stars in the local 30 Doradus starburst.

Author: Schneider FRN, Sana H, Evans CJ, Bestenlehner JM, Castro N, Fossati L, Gräfener G, Langer N, Ramírez-Agudelo OH, Sabín-Sanjulián C, Simón-Díaz S, Tramper F, Crowther PA, de Koter A, de Mink SE, Dufton PL, Garcia M, Gieles M, Hénault-Brunet V, Herrero A, Izzard RG, Kalari V, Lennon DJ, Maíz Apellániz J, Markova N, Najarro F, Podsiadlowski P, Puls J, Taylor WD, van Loon JT, Vink JS, and Norman C
Abstract: The 30 Doradus star-forming region in the Large Magellanic Cloud is a nearby analog of large star-formation events in the distant universe. We determined the recent formation history and the initial mass function (IMF) of massive stars in 30 Doradus on the basis of spectroscopic observations of 247 stars more massive than 15 solar masses ([Formula: see text]). The main episode of massive star formation began about 8 million years (My) ago, and the star-formation rate seems to have declined in the last 1 My. The IMF is densely sampled up to 200 [Formula: see text] and contains 32 ± 12% more stars above 30 [Formula: see text] than predicted by a standard Salpeter IMF. In the mass range of 15 to 200 [Formula: see text], the IMF power-law exponent is [Formula: see text], shallower than the Salpeter value of 2.35., (Copyright © 2018, American Association for the Advancement of Science.)
Published: 2018
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16. Swope Supernova Survey 2017a (SSS17a), the optical counterpart to a gravitational wave source.

Author: Coulter DA, Foley RJ, Kilpatrick CD, Drout MR, Piro AL, Shappee BJ, Siebert MR, Simon JD, Ulloa N, Kasen D, Madore BF, Murguia-Berthier A, Pan YC, Prochaska JX, Ramirez-Ruiz E, Rest A, and Rojas-Bravo C
Abstract: On 17 August 2017, the Laser Interferometer Gravitational-Wave Observatory (LIGO) and the Virgo interferometer detected gravitational waves (GWs) emanating from a binary neutron star merger, GW170817. Nearly simultaneously, the Fermi and INTEGRAL (INTErnational Gamma-Ray Astrophysics Laboratory) telescopes detected a gamma-ray transient, GRB 170817A. At 10.9 hours after the GW trigger, we discovered a transient and fading optical source, Swope Supernova Survey 2017a (SSS17a), coincident with GW170817. SSS17a is located in NGC 4993, an S0 galaxy at a distance of 40 megaparsecs. The precise location of GW170817 provides an opportunity to probe the nature of these cataclysmic events by combining electromagnetic and GW observations., (Copyright © 2017, American Association for the Advancement of Science.)
Published: 2017
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17. Electromagnetic evidence that SSS17a is the result of a binary neutron star merger.

Author: Kilpatrick CD, Foley RJ, Kasen D, Murguia-Berthier A, Ramirez-Ruiz E, Coulter DA, Drout MR, Piro AL, Shappee BJ, Boutsia K, Contreras C, Di Mille F, Madore BF, Morrell N, Pan YC, Prochaska JX, Rest A, Rojas-Bravo C, Siebert MR, Simon JD, and Ulloa N
Abstract: Eleven hours after the detection of gravitational wave source GW170817 by the Laser Interferometer Gravitational-Wave Observatory and Virgo Interferometers, an associated optical transient, SSS17a, was identified in the galaxy NGC 4993. Although the gravitational wave data indicate that GW170817 is consistent with the merger of two compact objects, the electromagnetic observations provide independent constraints on the nature of that system. We synthesize the optical to near-infrared photometry and spectroscopy of SSS17a collected by the One-Meter Two-Hemisphere collaboration, finding that SSS17a is unlike other known transients. The source is best described by theoretical models of a kilonova consisting of radioactive elements produced by rapid neutron capture (the r-process). We conclude that SSS17a was the result of a binary neutron star merger, reinforcing the gravitational wave result., (Copyright © 2017, American Association for the Advancement of Science.)
Published: 2017
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18. Light curves of the neutron star merger GW170817/SSS17a: Implications for r-process nucleosynthesis.

Author: Drout MR, Piro AL, Shappee BJ, Kilpatrick CD, Simon JD, Contreras C, Coulter DA, Foley RJ, Siebert MR, Morrell N, Boutsia K, Di Mille F, Holoien TW, Kasen D, Kollmeier JA, Madore BF, Monson AJ, Murguia-Berthier A, Pan YC, Prochaska JX, Ramirez-Ruiz E, Rest A, Adams C, Alatalo K, Bañados E, Baughman J, Beers TC, Bernstein RA, Bitsakis T, Campillay A, Hansen TT, Higgs CR, Ji AP, Maravelias G, Marshall JL, Bidin CM, Prieto JL, Rasmussen KC, Rojas-Bravo C, Strom AL, Ulloa N, Vargas-González J, Wan Z, and Whitten DD
Abstract: On 17 August 2017, gravitational waves (GWs) were detected from a binary neutron star merger, GW170817, along with a coincident short gamma-ray burst, GRB 170817A. An optical transient source, Swope Supernova Survey 17a (SSS17a), was subsequently identified as the counterpart of this event. We present ultraviolet, optical, and infrared light curves of SSS17a extending from 10.9 hours to 18 days postmerger. We constrain the radioactively powered transient resulting from the ejection of neutron-rich material. The fast rise of the light curves, subsequent decay, and rapid color evolution are consistent with multiple ejecta components of differing lanthanide abundance. The late-time light curve indicates that SSS17a produced at least ~0.05 solar masses of heavy elements, demonstrating that neutron star mergers play a role in rapid neutron capture (r-process) nucleosynthesis in the universe., (Copyright © 2017, American Association for the Advancement of Science.)
Published: 2017
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19. Imaging the water snow-line during a protostellar outburst.

Author: Cieza LA, Casassus S, Tobin J, Bos SP, Williams JP, Perez S, Zhu Z, Caceres C, Canovas H, Dunham MM, Hales A, Prieto JL, Principe DA, Schreiber MR, Ruiz-Rodriguez D, and Zurlo A
Abstract: A snow-line is the region of a protoplanetary disk at which a major volatile, such as water or carbon monoxide, reaches its condensation temperature. Snow-lines play a crucial role in disk evolution by promoting the rapid growth of ice-covered grains. Signatures of the carbon monoxide snow-line (at temperatures of around 20 kelvin) have recently been imaged in the disks surrounding the pre-main-sequence stars TW Hydra and HD163296 (refs 3, 10), at distances of about 30 astronomical units (au) from the star. But the water snow-line of a protoplanetary disk (at temperatures of more than 100 kelvin) has not hitherto been seen, as it generally lies very close to the star (less than 5 au away for solar-type stars). Water-ice is important because it regulates the efficiency of dust and planetesimal coagulation, and the formation of comets, ice giants and the cores of gas giants. Here we report images at 0.03-arcsec resolution (12 au) of the protoplanetary disk around V883 Ori, a protostar of 1.3 solar masses that is undergoing an outburst in luminosity arising from a temporary increase in the accretion rate. We find an intensity break corresponding to an abrupt change in the optical depth at about 42 au, where the elevated disk temperature approaches the condensation point of water, from which we conclude that the outburst has moved the water snow-line. The spectral behaviour across the snow-line confirms recent model predictions: dust fragmentation and the inhibition of grain growth at higher temperatures results in soaring grain number densities and optical depths. As most planetary systems are expected to experience outbursts caused by accretion during their formation, our results imply that highly dynamical water snow-lines must be considered when developing models of disk evolution and planet formation.
Published: 2016
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20. Suppressing star formation in quiescent galaxies with supermassive black hole winds.

Author: Cheung E, Bundy K, Cappellari M, Peirani S, Rujopakarn W, Westfall K, Yan R, Bershady M, Greene JE, Heckman TM, Drory N, Law DR, Masters KL, Thomas D, Wake DA, Weijmans AM, Rubin K, Belfiore F, Vulcani B, Chen YM, Zhang K, Gelfand JD, Bizyaev D, Roman-Lopes A, and Schneider DP
Abstract: Quiescent galaxies with little or no ongoing star formation dominate the population of galaxies with masses above 2 × 10(10) times that of the Sun; the number of quiescent galaxies has increased by a factor of about 25 over the past ten billion years (refs 1-4). Once star formation has been shut down, perhaps during the quasar phase of rapid accretion onto a supermassive black hole, an unknown mechanism must remove or heat the gas that is subsequently accreted from either stellar mass loss or mergers and that would otherwise cool to form stars. Energy output from a black hole accreting at a low rate has been proposed, but observational evidence for this in the form of expanding hot gas shells is indirect and limited to radio galaxies at the centres of clusters, which are too rare to explain the vast majority of the quiescent population. Here we report bisymmetric emission features co-aligned with strong ionized-gas velocity gradients from which we infer the presence of centrally driven winds in typical quiescent galaxies that host low-luminosity active nuclei. These galaxies are surprisingly common, accounting for as much as ten per cent of the quiescent population with masses around 2 × 10(10) times that of the Sun. In a prototypical example, we calculate that the energy input from the galaxy's low-level active supermassive black hole is capable of driving the observed wind, which contains sufficient mechanical energy to heat ambient, cooler gas (also detected) and thereby suppress star formation.
Published: 2016
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21. Two-parameter bifurcation study of the regularized long-wave equation.

Author: Podvigina O, Zheligovsky V, Rempel EL, Chian AC, Chertovskih R, and Muñoz PR
Abstract: We perform a two-parameter bifurcation study of the driven-damped regularized long-wave equation by varying the amplitude and phase of the driver. Increasing the amplitude of the driver brings the system to the regime of spatiotemporal chaos (STC), a chaotic state with a large number of degrees of freedom. Several global bifurcations are found, including codimension-two bifurcations and homoclinic bifurcations involving three-tori and the manifolds of steady waves, leading to the formation of chaotic saddles in the phase space. We identify four distinct routes to STC; they depend on the phase of the driver and involve boundary and interior crises, intermittency, the Ruelle-Takens scenario, the Feigenbaum cascade, an embedded saddle-node, homoclinic, and other bifurcations. This study elucidates some of the recently reported dynamical phenomena.
Published: 2015
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22. Impact of Noise on a Dynamical System: Prediction and Uncertainties from a Swarm-Optimized Neural Network.

Author: López-Caraballo CH, Lazzús JA, Salfate I, Rojas P, Rivera M, and Palma-Chilla L
Subjects: Artificial Intelligence, Time Factors, Uncertainty, Algorithms, Computer Simulation, Forecasting methods, Neural Networks, Computer
Abstract: An artificial neural network (ANN) based on particle swarm optimization (PSO) was developed for the time series prediction. The hybrid ANN+PSO algorithm was applied on Mackey-Glass chaotic time series in the short-term x(t + 6). The performance prediction was evaluated and compared with other studies available in the literature. Also, we presented properties of the dynamical system via the study of chaotic behaviour obtained from the predicted time series. Next, the hybrid ANN+PSO algorithm was complemented with a Gaussian stochastic procedure (called stochastic hybrid ANN+PSO) in order to obtain a new estimator of the predictions, which also allowed us to compute the uncertainties of predictions for noisy Mackey-Glass chaotic time series. Thus, we studied the impact of noise for several cases with a white noise level (σ(N)) from 0.01 to 0.1.
Published: 2015
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23. Astronomy. One good measure.

Author: Schreiber MR
Published: 2013
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24. DISCOVERY OF TWO VERY WIDE BINARIES WITH ULTRACOOL COMPANIONS AND A NEW BROWN DWARF AT THE L/T TRANSITION.

Author: Mužić K, Radigan J, Jayawardhana R, Ivanov VD, Faherty JK, Kurtev RG, Núñez A, Boffin HMJ, Hainaut O, Cruz K, Jones D, Metchev S, Tyndall A, and Borissova J
Abstract: We present the discovery and spectroscopic follow-up of a nearby late-type L dwarf (2M0614+3950), and two extremely wide very-low-mass binary systems (2M0525-7425AB and 2M1348-1344AB), resulting from our search for common proper motion pairs containing ultracool components in the Two Micron All Sky Survey (2MASS) and the Wide-field Infrared Survey Explorer (WISE) catalogs. The near-infrared spectrum of 2M0614+3950 indicates a spectral type L9 ± 1 object residing at a distance of 26.0 ± 1.8 pc. The optical spectrum of 2M0525-7425A reveals an M3.0 ± 0.5 dwarf primary, accompanied by a secondary previously classified as L2. The system has an angular separation of ~ 44″, equivalent to ~ 2000 AU at distance of 46.0 ± 3.0 pc. Using optical and infrared spectra, respectively, we classify the components of 2M1348-1344AB as M4.5 ± 0.5 and T5.5 ± 1. The angular separation of ~ 68″ is equivalent to ~ 1400 AU at a distance of 20.7 ± 1.4 pc. 2M1348-1344AB is one of only six very wide (separation > 1000 AU) systems containing late T dwarfs known to date.
Published: 2012
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25. Do hummingbirds see in ultraviolet?

Author: Curé M and Palacios AG
Abstract: We present a numerical model to fit the electroretinogram (ERG), a gross evoked eye visual potential, that originate in the retina through photons absorption by photoreceptors and then involve the contribution form others retinal neurons. We use the ERG measured in a hummingbird, to evaluate the most likely retinal mechanism - cones visual pigments and oil-droplets - that participate in their high dimensional tetra or pentachromatic color hyperspace. The model - a nonlinear fit - appears to be a very useful tool to predict the underlying contribution visual mechanism for a variety of retinal preparation.
Published: 2009
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25 results on '"Departamento de Física y Astronomía"'

1. Microlensing of quasar ultraviolet iron emission

2. The Pristine Inner Galaxy Survey (PIGS) II: Uncovering the most metal-poor populations in the inner Milky Way

3. VLT/SPHERE astrometric confirmation and orbital analysis of the brown dwarf companion HR 2562 B

4. New constraints on the disk characteristics and companion candidates around T Chamaeleontis with VLT/SPHERE

5. INFRARED COLOR SELECTION OF MASSIVE GALAXIES AT z \textgreater 3

6. [C II] and ^(12)CO(1-0) Emission Maps in HLSJ091828.6+514223: A Strongly Lensed Interacting System at z=5.24

7. An extended Herschel drop-out source in the center of AS1063: a normal dusty galaxy at z = 6.1 or SZ substructures?

8. A bright z = 5.2 lensed submillimeter galaxy in the field of Abell 773. HLSJ091828.6+514223

9. Improving the identification of high-z Herschel sources with position priors and optical/NIR and FIR/mm photometric redshifts

10. Mid-infrared spectroscopy of lensed galaxies at 1 < z < 3: The nature of sources near the MIPS confusion limit

11. Spitzer and Hubble Space Telescope Constraints on the Physical Properties of the z~7 Galaxy Strongly Lensed by A2218

12. A magnetic massive star has experienced a stellar merger.

13. Response to Comment on "An excess of massive stars in the local 30 Doradus starburst".

14. Investigation of EBT3 radiochromic film's response to humidity.

15. An excess of massive stars in the local 30 Doradus starburst.

16. Swope Supernova Survey 2017a (SSS17a), the optical counterpart to a gravitational wave source.

17. Electromagnetic evidence that SSS17a is the result of a binary neutron star merger.

18. Light curves of the neutron star merger GW170817/SSS17a: Implications for r-process nucleosynthesis.

19. Imaging the water snow-line during a protostellar outburst.

20. Suppressing star formation in quiescent galaxies with supermassive black hole winds.

21. Two-parameter bifurcation study of the regularized long-wave equation.

22. Impact of Noise on a Dynamical System: Prediction and Uncertainties from a Swarm-Optimized Neural Network.

23. Astronomy. One good measure.

24. DISCOVERY OF TWO VERY WIDE BINARIES WITH ULTRACOOL COMPANIONS AND A NEW BROWN DWARF AT THE L/T TRANSITION.

25. Do hummingbirds see in ultraviolet?

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25 results on '"Departamento de Física y Astronomía"'

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