45 results on '"Graeme Salter"'
Search Results
2. PRAGMATISM AS A TEACHING APPROACH FOR ENGAGING STUDENTS IN COMPUTING EDUCATION
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Shaleeza Sohail and Graeme Salter
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- 2022
3. OVERCOMING THE HORSELESS CARRIAGE SYNDROME: METHODS TO ENCOURAGE PEDAGOGICAL RE-ENGINEERING
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Graeme Salter
- Published
- 2022
4. The Importance of Using a Unified Model to Define Adaptive Learning Environments.
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Matthew Hathaway, Stephen Hansen, and Graeme Salter
- Published
- 2004
5. Investigating three Sirius-like systems with SPHERE
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H. M. Schmid, Arthur Vigan, T. O. B. Schmidt, Mickael Bonnefoy, M. Keppler, E. Sissa, Markus Kasper, Antonio Garufi, S. Petrus, David Mouillet, E. L. Rickman, Sebastian Daemgen, M. Cudel, Alice Zurlo, J. L. Beuzit, Janis Hagelberg, Raffaele Gratton, Roxanne Ligi, J. Melendez, Anne-Lise Maire, François Ménard, Tomas Stolker, D. Gasparri, F. Rigal, Daniel Rouan, C. Soenke, E. Cascone, Matthias Samland, Silvano Desidera, R. Galicher, Christian Ginski, Gael Chauvin, Valentina D'Orazi, M. R. Mayer, A. Potier, A-M. Lagrange, Graeme Salter, Francois Wildi, H. Le Coroller, Maud Langlois, T. A. Pacheco, Henning Avenhaus, C. Desgrange, Beth Biller, C. Lazzoni, Mariangela Bonavita, Wolfgang Brandner, Markus Janson, Markus Feldt, S. Mazevet, N. Engler, Julien Girard, C. Perrot, Dino Mesa, J. Lannier, C. Fontanive, S. Hunziker, T. Moulin, S. Peretti, Joany Andreina Manjarres Ramos, M. Lombart, Riccardo Claudi, Philippe Delorme, A. Boccaletti, University of Arizona, 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), INAF - Osservatorio Astronomico di Padova (OAPD), Istituto Nazionale di Astrofisica (INAF), Stockholm University, 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), Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève = University of Geneva (UNIGE), Max Planck Institute for Radio Astronomy, 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, European Southern Observatory (ESO), Universidad de Chile = University of Chile [Santiago] (UCHILE), University of Edinburgh, 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)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Observatoire de la Côte d'Azur (OCA), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Chaire IPAG 'Entreprise Inclusive' (IPAG Business School), IPAG Business School, Observatoire de Paris, Université Paris sciences et lettres (PSL), Department of Biochemistry and Molecular Biology, Mayo Clinic, École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Low Energy Astrophysics (API, FNWI), 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), and Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)
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Angular momentum ,530 Physics ,Sirius ,CD-56 7708 ,HD 114174 ,FOS: Physical sciences ,Individual ,Astrophysics ,01 natural sciences ,Nucleosynthesis ,0103 physical sciences ,Asymptotic giant branch ,Solar and Stellar Astrophysics ,Abundances ,General ,010303 astronomy & astrophysics ,Solar and Stellar Astrophysics (astro-ph.SR) ,Physics ,[SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph] ,010308 nuclear & particles physics ,520 Astronomy ,Binaries ,White dwarf ,Astronomy and Astrophysics ,HD 2133 ,Stars ,White Dwarfs ,Orbit ,Photometry (astronomy) ,Astrophysics - Solar and Stellar Astrophysics ,13. Climate action ,Space and Planetary Science ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] - Abstract
Sirius-like systems are wide binaries composed of a white dwarf (WD) and a companion of a spectral type earlier than M0. The WD progenitor evolves in isolation, but its wind during the AGB phase pollutes the companion surface and transfers some angular momentum. Within SHINE survey that uses SPHERE at the VLT, we acquired images of HD2133, HD114174, and CD-567708 and combined this data with high resolution spectra of the primaries, TESS, and literature data. We performed accurate abundance analyses for the MS. We found brighter J and K magnitudes for HD114174B than obtained previously and extended the photometry down to 0.95 micron. Our new data indicate a higher temperature and then shorter cooling age (5.57+/-0.02 Gyr) and larger mass (0.75+/-0.03 Mo) for this WD than previously assumed. This solved the discrepancy previously found with the age of the MS star. The two other WDs are less massive, indicating progenitors of ~1.3 Mo and 1.5-1.8 Mo for HD2133B and CD-56 7708B, respectively. We were able to derive constraints on the orbit for HD114174 and CD-56 7708. The composition of the MS stars agrees fairly well with expectations from pollution by the AGB progenitors of the WDs: HD2133A has a small enrichment of n-capture elements, which is as expected for pollution by an AGB star with a mass 3.0 Mo. On the other hand, none of these stars show the excesses of C that are expected to go along with those of n-capture elements. This might be related to the fact that these stars are at the edges of the mass range where we expect nucleosynthesis related to thermal pulses., Accepted on Astronomy and Astrophysics. 19 pages, 15 figures
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- 2021
6. The search for disks or planetary objects around directly imaged companions: A candidate around DH Tau B
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E. L. Rickman, Markus Janson, Anthony Boccaletti, C. Fontanive, Matthias Samland, C. Lazzoni, S. Peretti, Francois Wildi, Mickael Bonnefoy, M. Houllé, T. Schmidt, C. Perrot, André Müller, Graeme Salter, Miriam Keppler, Raphaël Galicher, E. Sissa, Janis Hagelberg, Anne-Lise Maire, Th. Henning, Silvano Desidera, Arthur Vigan, Alice Zurlo, Steve Ertel, Beth Biller, Ken Rice, J. Lannier, Maud Langlois, R. Asensio-Torres, Wolfgang Brandner, Gael Chauvin, Faustine Cantalloube, R. G. Gratton, Esther Buenzli, Jean-Luc Beuzit, M. Cudel, Anthony Cheetham, David Mouillet, M. Kasper, Philippe Delorme, Dino Mesa, Anne-Marie Lagrange, J. L. Baudino, Mariangela Bonavita, Michael Meyer, M. Feldt, Eckhart Spalding, H. LeCoroller, 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), 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)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), 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 = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)
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astro-ph.SR ,010504 meteorology & atmospheric sciences ,530 Physics ,Library science ,FOS: Physical sciences ,Astrophysics ,01 natural sciences ,0103 physical sciences ,Coordination network ,Astrophysics::Solar and Stellar Astrophysics ,European commission ,010303 astronomy & astrophysics ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,ComputingMilieux_MISCELLANEOUS ,Solar and Stellar Astrophysics (astro-ph.SR) ,0105 earth and related environmental sciences ,Physics ,[PHYS]Physics [physics] ,Earth and Planetary Astrophysics (astro-ph.EP) ,[SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph] ,520 Astronomy ,European research ,Astronomy and Astrophysics ,500 Science ,Methods observational ,Astrophysics - Solar and Stellar Astrophysics ,Space and Planetary Science ,astro-ph.EP ,Christian ministry ,Astrophysics::Earth and Planetary Astrophysics ,Astrophysics - Instrumentation and Methods for Astrophysics ,Astrophysics - Earth and Planetary Astrophysics ,astro-ph.IM - Abstract
In recent decades, thousands of substellar companions have been discovered with both indirect and direct methods of detection. In this paper, we focus our attention on substellar companions detected with the direct imaging technique, with the primary goal of investigating their close surroundings and looking for additional companions and satellites, as well as disks and rings. Any such discovery would shed light on many unresolved questions, particularly with regard to their possible formation mechanisms. To reveal bound features of directly imaged companions we need to suppress the contribution from the source itself. Therefore, we developed a method based on the negative fake companion (NEGFC) technique that first estimates the position in the field of view (FoV) and the flux of the imaged companion, then subtracts a rescaled model point spread function (PSF) from the imaged companion. Next it performs techniques, such as angular differential imaging (ADI), to further remove quasi-static patterns of the star. We applied the method to the sample of substellar objects observed with SPHERE during the SHINE GTO survey. Among the 27 planets and brown dwarfs we analyzed, we detected a possible point source close to DH Tau B. This candidate companion was detected in four different SPHERE observations, with an estimated mass of $\sim 1$ M\textsubscript{Jup}, and a mass ratio with respect to the brown dwarf of $1/10$. This binary system, if confirmed, would be the first of its kind, opening up interesting questions for the formation mechanism, evolution, and frequency of such pairs. In order to address the latter, the residuals and contrasts reached for 25 companions in the sample of substellar objects observed with SPHERE were derived. If the DH Tau Bb companion is real, the binary fraction obtained is $\sim 7\%$, which is in good agreement with the results obtained for field brown dwarfs., Comment: 19 pages, 17 figures
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- 2020
- Full Text
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7. Strategies for the Use of Synchronous Computer-Mediated Communication in Education.
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Graeme Salter
- Published
- 2002
- Full Text
- View/download PDF
8. Online Assessment with Large Classes: Issues, Methodologies and Case Studies.
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Paul Davies, Steve Hansen, Graeme Salter, and Keith Simpson
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- 1999
9. The Take-Up of Web Technology: Adoption & Diffusion into Mainstream Teaching.
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Steve Hansen, Graeme Salter, and Paul Davies
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- 1999
10. Increasing the Adoption of Online Teaching by Modelling Good Practice.
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Graeme Salter, Steve Hansen, and Paul Davies
- Published
- 1999
11. First resolved observations of a highly asymmetric debris disc around HD 160305 with VLT/SPHERE★★★
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Anne-Marie Lagrange, Graeme Salter, S. Daemgen, Alan Loh, L. Weber, Johan Olofsson, Cyril Petit, Dino Mesa, M. Llored, Clément Perrot, Anthony K. Cheetham, Arthur Vigan, Philippe Delorme, Elodie Choquet, J. Lannier, Eric Lagadec, P. Janin-Potiron, Beth Biller, Maud Langlois, A. Roux, Jean-Tristan Buey, S. Peretti, Raffaele Gratton, A. Pavlov, Markus Feldt, Mickael Bonnefoy, Wolfgang Brandner, Anne-Lise Maire, Jean-Charles Augereau, Sergio Messina, E. Sissa, François Ménard, Quentin Kral, Philippe Thebault, Silvano Desidera, Gael Chauvin, David Mouillet, Esther Buenzli, Anthony Boccaletti, 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), Pontificia Universidad Católica de Valparaíso (PUCV), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), 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), INAF - Osservatorio Astronomico di Padova (OAPD), Istituto Nazionale di Astrofisica (INAF), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, STAR Institute, Université de Liège, INAF - Osservatorio Astrofisico di Catania (OACT), Universidad de Valparaiso [Chile], Institute for Astronomy [Edinburgh] (IfA), University of Edinburgh, Institute for Particle Physics and Astrophysics [ETH Zürich] (IPA), 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), Unidad Mixta Internacional Franco-Chilena de Astromia, Universidad de Chile (CNRS/INSU), Geneva Observatory, Université de Genève = University of Geneva (UNIGE), Observatoire de la Côte d'Azur (OCA), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), 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), Instituto de Astronomia y ciencias Planetarias de Atacama (INCT), Universidad de Atacama, Observatoire Astronomique de l'Université de Genève (ObsGE), DOTA, ONERA, Université Paris Saclay (COmUE) [Châtillon], ONERA-Université Paris Saclay (COmUE), ANR-16-CE31-0013,PLANET-FORMING-DISKS,De meilleurs modèles pour de meilleures données(2016), University of Geneva [Switzerland], 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), Université de Genève (UNIGE), 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 Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-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), 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), DOTA, ONERA, Université Paris Saclay [Châtillon], ONERA-Université Paris-Saclay, Institut national des sciences de l'Univers (INSU - CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), 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)
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Planetesimal ,Brightness ,individual: HD160305 ,methods: observational ,techniques: high angular resolution ,planet-disk interactions ,techniques: image processing [scattering ,stars] ,media_common.quotation_subject ,[SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP] ,FOS: Physical sciences ,Context (language use) ,techniques: image processing ,Astrophysics ,01 natural sciences ,Asymmetry ,Planet ,0103 physical sciences ,Surface brightness ,010303 astronomy & astrophysics ,stars: individual: HD160305 ,Astrophysics::Galaxy Astrophysics ,media_common ,Physics ,Earth and Planetary Astrophysics (astro-ph.EP) ,010308 nuclear & particles physics ,Scattering ,scattering ,Astronomy and Astrophysics ,Planetary system ,13. Climate action ,Space and Planetary Science ,Astrophysics::Earth and Planetary Astrophysics ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,Astrophysics - Earth and Planetary Astrophysics - Abstract
Context. Direct imaging of debris discs gives important information about their nature, their global morphology, and allows us to identify specific structures possibly in connection with the presence of gravitational perturbers. It is the most straightforward technique to observe planetary systems as a whole. Aims. We present the first resolved images of the debris disc around the young F-type star HD 160305, detected in scattered light using the VLT/SPHERE instrument in the near infrared. Methods. We used a post-processing method based on angular differential imaging and synthetic images of debris discs produced with a disc modelling code (GRaTer) to constrain the main characteristics of the disc around HD 160305. All of the point sources in the field of the IRDIS camera were analysed with an astrometric tool to determine whether they are bound objects or background stars. Results. We detect a very inclined (~ 82{\deg}) ring-like debris disc located at a stellocentric distance of about 86au (deprojected width ~27 au). The disc displays a brightness asymmetry between the two sides of the major axis, as can be expected from scattering properties of dust grains. We derive an anisotropic scattering factor g>0.5. A second right-left asymmetry is also observed with respect to the minor axis. We measure a surface brightness ratio of 0.73 $\pm$ 0.18 between the bright and the faint sides. Because of the low signal-to-noise ratio (S/N) of the images we cannot easily discriminate between several possible explanations for this left-right asymmetry, such as perturbations by an unseen planet, the aftermath of the breakup of a massive planetesimal, or the pericenter glow effect due to an eccentric ring. Two epochs of observations allow us to reject the companionship hypothesis for the 15 point sources present in the field., Comment: 13 pages
- Published
- 2019
12. SAFARI – I. A SPHERE discovery of a super metal-rich M-dwarf companion to the star HD 86006
- Author
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M. I. Jones, Graeme Salter, Julien Girard, B. Pantoja, James S. Jenkins, Arthur Vigan, Universidad de Chile, European Southern Observatory [Santiago] (ESO), European Southern Observatory (ESO), 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), and Universidad de Chile = University of Chile [Santiago] (UCHILE)
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Physics ,Field (physics) ,[SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph] ,010308 nuclear & particles physics ,Star (game theory) ,FOS: Physical sciences ,Astronomy and Astrophysics ,stars: solar-type ,Astrophysics ,Type (model theory) ,Stellar classification ,instrumentation: adaptive optics ,01 natural sciences ,binaries: visual ,Spectral line ,Radial velocity ,Stars ,Orbit ,Astrophysics - Solar and Stellar Astrophysics ,Space and Planetary Science ,stars: low-mass ,0103 physical sciences ,techniques: radial velocities ,010303 astronomy & astrophysics ,Solar and Stellar Astrophysics (astro-ph.SR) - Abstract
We report the direct detection of a fully convective, early-to-mid M-dwarf companion orbiting the star HD 86006, using ESO-SPHERE during Science Verification as part of the SAFARI program. HARPS+CORALIE radial velocity measurements first indicated a possible companion. Such work highlights the synergies that are now possible between these two observing methods. We studied the companion by comparing our observed spectra with BT-Settl models and template spectra, measuring spectral indices to obtain a spectral type, and used a joint radial velocity and astrometric fit to simulate the companion's orbit. The companion was found to be 4.14 mag fainter than the primary in the H2 band, residing at a physical separation of $\sim$ 25 AU, with a $T_\mathrm{eff}$ and spectral type of 3321 $\pm$ 111 K and M 4.1 $\pm$ 1.1, respectively. We note that the age derived from BT-Settl models for such a star is too low by over two orders of magnitude, similar to other known field mid-M stars. We searched for the radial velocity companion to HD 90520 without any clear detection, however we reached a low contrast level of $\Delta$H2 = 10.3 mag (or $1.3 * 10^{-4}$) at 0.2$''$ and 12.6 mag (or $10^{-5}$) at 0.5$''$, allowing us to rule out any low-mass companions with masses of 0.07 and 0.05 M$_{\odot}$ at these separations. This discovery provides us with the exciting opportunity to better constrain the mass-luminosity relation for low-mass stars in the super metal-rich domain, expanding our understanding of the most-common types of stars and substellar objects., Comment: Accepted for publication in MNRAS
- Published
- 2018
13. Dynamical masses of M-dwarf binaries in young moving groups. I. The case of TWA 22 and GJ 2060
- Author
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Stephen Durkan, Thomas Henning, Derek Homeier, T. Schmidt, Markus Janson, Eric Stadler, Julien Girard, Jean-Philippe Berger, F. Allard, Sylvestre Lacour, Jean-Louis Monin, J.-B. Le Bouquin, Silvano Desidera, Raffaele Gratton, Dino Mesa, A. Pavlov, C. Bergfors, Joany Andreina Manjarres Ramos, Joshua E. Schlieder, Roxanne Ligi, Mickael Bonnefoy, L. Rodet, A. Bazzon, P. Delorme, Wolfgang Brandner, Sergio Messina, Matthias Samland, R. Rigal, A. Grandjean, A. Delboulbé, Stéphane Udry, Damien Ségransan, A. Boccaletti, Anne-Lise Maire, Markus Feldt, H. Beust, Janis Hagelberg, Gael Chauvin, Anne-Marie Lagrange, Maud Langlois, J.-L. Beuzit, Michael Meyer, D. Maurel, François Ménard, J. Lannier, Ronald Roelfsema, Arthur Vigan, Beth Biller, Graeme Salter, L. Weber, and S. Peretti
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Brown dwarf ,FOS: Physical sciences ,Context (language use) ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,visual [Binaries] ,01 natural sciences ,Spectral line ,010309 optics ,low-mass [Stars] ,Planet ,pre-main sequence [Stars] ,0103 physical sciences ,Astrophysics::Solar and Stellar Astrophysics ,Beta Pictoris ,010303 astronomy & astrophysics ,individual: TWA 22 [Stars] ,Astrophysics::Galaxy Astrophysics ,Solar and Stellar Astrophysics (astro-ph.SR) ,Earth and Planetary Astrophysics (astro-ph.EP) ,Orbital elements ,Physics ,Astronomy and Astrophysics ,Astrometry ,high angular resolution [Techniques] ,Stars ,Astrophysics - Solar and Stellar Astrophysics ,individual: GJ 2060 [Stars] ,Space and Planetary Science ,Astrophysics::Earth and Planetary Astrophysics ,Astrophysics - Earth and Planetary Astrophysics - Abstract
Evolutionary models are widely used to infer the mass of stars, brown dwarfs, and giant planets. Their predictions are thought to be less reliable at young ages ($, Comment: Accepted for publication in A&A. 26 pages, 22 figures, 12 tables
- Published
- 2018
14. Imaging radial velocity planets with SPHERE
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Anne-Marie Lagrange, Clément Perrot, Claire Moutou, Arthur Vigan, P. J. Potiron, Dino Mesa, Jose Ramos, C. Petit, Esther Buenzli, Mickael Bonnefoy, Matthias Meyer, Tanmay Bhowmik, Markus Feldt, Silvano Desidera, Maud Langlois, Anne-Lise Maire, Markus Janson, Graeme Salter, C. Lazzoni, T. Schmidt, Jean-Luc Beuzit, Alain Delboulbé, M. Cudel, Beth Biller, Mariangela Bonavita, Wolfgang Brandner, S. Peretti, Sylvain Rochat, Janis Hagelberg, Valentina D'Orazi, Anthony Boccaletti, Alice Zurlo, Baptiste Lavie, Sergio Messina, Raffaele Gratton, F. Rigal, Gael Chauvin, David Mouillet, J. Lannier, E. Sissa, Universidad Diego Portales [Santiago] (UDP), 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), Instituto de Astronomia y ciencias Planetarias de Atacama (INCT), Universidad de Atacama, INAF - Osservatorio Astronomico di Padova (OAPD), Istituto Nazionale di Astrofisica (INAF), INAF - Osservatorio Astrofisico di Catania (OACT), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), University of Edinburgh, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, Institute for Particle Physics and Astrophysics [ETH Zürich] (IPA), Department of Physics [ETH Zürich] (D-PHYS), 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), Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève (UNIGE), Stockholm University, 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), University of Michigan [Ann Arbor], University of Michigan System, Observatoire de la Côte d'Azur (OCA), Centre National de la Recherche Scientifique (CNRS), DOTA, ONERA, Université Paris Saclay [Palaiseau], ONERA-Université Paris-Saclay, Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), 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]), 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), 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 - 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)-Centre National de la Recherche Scientifique (CNRS), DOTA, ONERA, Université Paris Saclay (COmUE) [Palaiseau], ONERA-Université Paris Saclay (COmUE), 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 de Genève = University of Geneva (UNIGE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
FOS: Physical sciences ,spectrographs -methods: data analysis [Instrumentation] ,Astrophysics ,01 natural sciences ,GJ 676A ,010309 optics ,ETOILE ,[SPI]Engineering Sciences [physics] ,RADIAL VELOCITY ,individual: HD142 [Stars] ,Planet ,0103 physical sciences ,Astrophysics::Solar and Stellar Astrophysics ,ANALYSE DONNEES ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,010303 astronomy & astrophysics ,Solar and Stellar Astrophysics (astro-ph.SR) ,Earth and Planetary Astrophysics (astro-ph.EP) ,Physics ,[PHYS]Physics [physics] ,SPECTROGRAPHE ,radial velocities [Techniques] ,imaging spectroscopy [Techniques] ,IMAGING SPECTROSCOPY ,Astrophysics::Instrumentation and Methods for Astrophysics ,Astronomy and Astrophysics ,Planetary system ,Exoplanet ,Starlight ,Radial velocity ,Stars ,Orbit ,Planetary systems ,Astrophysics - Solar and Stellar Astrophysics ,Space and Planetary Science ,[SDU]Sciences of the Universe [physics] ,HD39091 ,HIP 70849 ,Astrophysics::Earth and Planetary Astrophysics ,Astrophysics - Instrumentation and Methods for Astrophysics ,SYSTEME PLANETAIRE ,Astrophysics - Earth and Planetary Astrophysics ,Data reduction - Abstract
We present observations with the planet finder SPHERE of a selected sample of the most promising radial velocity (RV) companions for high-contrast imaging. Using a Monte Carlo simulation to explore all the possible inclinations of the orbit of wide RV companions, we identified the systems with companions that could potentially be detected with SPHERE. We found the most favorable RV systems to observe are : HD\,142, GJ\,676, HD\,39091, HIP\,70849, and HD\,30177 and carried out observations of these systems during SPHERE Guaranteed Time Observing (GTO). To reduce the intensity of the starlight and reveal faint companions, we used Principle Component Analysis (PCA) algorithms alongside angular and spectral differential imaging. We injected synthetic planets with known flux to evaluate the self-subtraction caused by our data reduction and to determine the 5$\sigma$ contrast in the J band $vs$ separation for our reduced images. We estimated the upper limit on detectable companion mass around the selected stars from the contrast plot obtained from our data reduction. Although our observations enabled contrasts larger than 15 mag at a few tenths of arcsec from the host stars, we detected no planets. However, we were able to set upper mass limits around the stars using AMES-COND evolutionary models. We can exclude the presence of companions more massive than 25-28 \MJup around these stars, confirming the substellar nature of these RV companions., Comment: 14 pages, 11 figures, accepted by MNRAS
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- 2018
15. Testing giant planet formation in the transitional disk of SAO 206462 using deep VLT/SPHERE imaging
- Author
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Christian Thalmann, Gael Chauvin, Dino Mesa, M. Millward, J. Lannier, T. Buey, Alice Zurlo, C. Perrot, S. Messina, Arthur Vigan, Carsten Dominik, Anne-Lise Maire, Silvano Desidera, R. Galicher, Anne-Marie Lagrange, Adriana Pohl, Matthias Samland, Thayne Currie, Anthony Boccaletti, Enrico Giro, Mickael Bonnefoy, André Müller, E. Sissa, Norbert Hubin, Thierry Fusco, Markus Feldt, Michael Meyer, Maud Langlois, Tomas Stolker, Raffaele Gratton, Wolfgang Brandner, Jose Ramos, D. Le Mignant, Esther Buenzli, Stéphane Udry, Carol A. Grady, Christian Ginski, R. van Boekel, Graeme Salter, L. Weber, Beth Biller, Thomas Henning, S. Peretti, Eric Stadler, Sascha P. Quanz, Low Energy Astrophysics (API, FNWI), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), INAF - Osservatorio Astrofisico di Catania (OACT), Istituto Nazionale di Astrofisica (INAF), European Southern Observatory [Santiago] (ESO), European Southern Observatory (ESO), Institute for Astronomy [Edinburgh] (IfA), University of Edinburgh, National Astronomical Observatory of Japan (NAOJ), GSFC Exoplanets and Stellar Astrophysics Laboratory, NASA Goddard Space Flight Center (GSFC), 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), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), York Creek Observatory, Heidelberg University, International Max Planck Research School on Astrophysics (IMPRS), 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), 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), Department of Astronomy University of Michigan, University of Michigan [Ann Arbor], University of Michigan System-University of Michigan System, 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), Universidad Diego Portales [Santiago] (UDP), Universidad de Santiago de Chile [Santiago] (USACH), INAF - Osservatorio Astronomico di Padova (OAPD), ONERA - The French Aerospace Lab [Châtillon], ONERA-Université Paris Saclay (COmUE), Leiden Observatory [Leiden], Universiteit Leiden [Leiden], Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève (UNIGE), 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), 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), Universiteit Leiden, Université de Genève = University of Geneva (UNIGE), Exoplanets and Stellar Astrophysics Lab, 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), 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), 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), ONERA, Astronomical Institute Anton Pannekoek, University of Amsterdam, INAF-Osservatorio Astrofisico di Catania (INAF-OACt), Institute for Astronomy, The University of Edinburgh, Royal Observatory, Blackford Hill View, Edinburgh, EH9 3HJ, UK, National Astronomical Observatory of Japan, Subaru Telescope, Hilo, HI, 96720, USA, Exoplanets and Stellar Astrophysics Laboratory, NASA Goddard Space Flight Center, 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, York Creek Observatory, Georgetown, Tasmania, Australia, Department of Astronomy, University of Michigan, 1085 S. University Ave, Ann Arbor, MI, 48109-1107, USA, Institute for Astronomy, Department of Physics, ETH Zürich, Nucleo de Astronomia, Facultad de Ingenieria, Universidad Diego Portales, Av. Ejercito 441, Santiago, Chile, INAF-Osservatorio Astronomico di Padova, Leiden Observatory, and ISDC, Geneva Observatory, University of Geneva
- Subjects
IMAGE PROCESSING ,INDIVIDUAL ,FOS: Physical sciences ,Context (language use) ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,OPTIQUE ADAPTATIVE ,01 natural sciences ,Density wave theory ,Jupiter ,VLT ,DATA ANALYSIS ,SPHERE ,Planet ,TECHNIQUES ,0103 physical sciences ,010306 general physics ,010303 astronomy & astrophysics ,Spiral ,Astrophysics::Galaxy Astrophysics ,Earth and Planetary Astrophysics (astro-ph.EP) ,Physics ,SAO 206462 (HD 135344B) ,Spiral galaxy ,[SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph] ,Giant planet ,HIGH ANGULAR RESOLUTION ,Astronomy and Astrophysics ,SPECTROSCOPIC ,13. Climate action ,Space and Planetary Science ,METHODS ,Astrophysics::Earth and Planetary Astrophysics ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,Protoplanet ,STARS ,Astrophysics - Earth and Planetary Astrophysics ,PLANETARY DISKS - Abstract
Context. The SAO 206462 (HD 135344B) disk is one of the few known transitional disks showing asymmetric features in scattered light and thermal emission. Near-infrared scattered-light images revealed two bright outer spiral arms and an inner cavity depleted in dust. Giant protoplanets have been proposed to account for the disk morphology. Aims. We aim to search for giant planets responsible for the disk features and, in the case of non-detection, to constrain recent planet predictions using the data detection limits. Methods. We obtained new high-contrast and high-resolution total intensity images of the target spanning the Y to the K bands (0.95-2.3 mic) using the VLT/SPHERE near-infrared camera and integral field spectrometer. Results. The spiral arms and the outer cavity edge are revealed at high resolutions and sensitivities without the need for image post-processing techniques, which introduce photometric biases. We do not detect any close-in companions. For the derivation of the detection limits on putative giant planets embedded in the disk, we show that the knowledge of the disk aspect ratio and viscosity is critical for the estimation of the attenuation of a planet signal by the protoplanetary dust because of the gaps that these putative planets may open. Given assumptions on these parameters, the mass limits can vary from ~2-5 to ~4-7 Jupiter masses at separations beyond the disk spiral arms. The SPHERE detection limits are more stringent than those derived from archival NaCo/L' data and provide new constraints on a few recent predictions of massive planets (4-15 MJ) based on the spiral density wave theory. The SPHERE and ALMA data do not favor the hypotheses on massive giant planets in the outer disk (beyond 0.6). There could still be low-mass planets in the outer disk and/or planets inside the cavity., A&A, in press. 16 pages, 17 figures. Updated to match proofs
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- 2017
16. SPHERE/SHINE reveals concentric rings in the debris disk of HIP 73145
- Author
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Gael Chauvin, A-M. Lagrange, Dino Mesa, J. Lannier, C. Perrot, Graeme Salter, Johan Olofsson, S. Peretti, Th. Henning, Arthur Vigan, Ágnes Kóspál, E. Sissa, P. Ábrahám, Anne-Lise Maire, Anthony Boccaletti, Zahed Wahhaj, Mickael Bonnefoy, Julien Milli, Raffaele Gratton, Maud Langlois, Esther Buenzli, Silvano Desidera, Attila Moór, Markus Feldt, François Ménard, 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), Laboratoire d'Astrophysique de Marseille (LAM), 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)
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010504 meteorology & atmospheric sciences ,Field (physics) ,FOS: Physical sciences ,Context (language use) ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,Primary (astronomy) ,0103 physical sciences ,Astrophysics::Solar and Stellar Astrophysics ,010303 astronomy & astrophysics ,Solar and Stellar Astrophysics (astro-ph.SR) ,Astrophysics::Galaxy Astrophysics ,0105 earth and related environmental sciences ,Physics ,Earth and Planetary Astrophysics (astro-ph.EP) ,Debris disk ,[SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph] ,Astronomy and Astrophysics ,Debris ,Stars ,Wavelength ,Astrophysics - Solar and Stellar Astrophysics ,Space and Planetary Science ,Substructure ,Astrophysics::Earth and Planetary Astrophysics ,Astrophysics - Earth and Planetary Astrophysics - Abstract
The debris disk of HIP73145 has been detected in scattered light in the near-IR, and at far-IR wavelengths before, but no substructure has been seen so far. Detection of such substructures in combination with detailed modeling can hint at the presence of perturbing planetary bodies, or reveal other mechanisms acting to replenish gas and dust reservoirs and forming structures such as spirals or rings. We obtained multiwavelength images with SPHERE in the near-IR in the H2 and H3 bands with the IRDIS camera and a 0.95-1.35 micron spectral cube with the IFS. Data were acquired in pupil-tracking mode, thus allowing for angular differential imaging. The SPHERE standard suite of angular differential imaging algorithms was applied. ALMA Band 6 observations complement the SPHERE data. We detect a bright ring of scattered light plus more structures inside, at least one of them forming a secondary, concentric ring with the first. This is the first detection of this disk in total-intensity scattered light. A second object is detected in the field at high contrast but concluded to be a background star. Forward modeling yields information on the primary parameters of the disk and confirms that the detected substructures are not due to the data analysis approach, which sometimes leads to spurious structures. We detect a series of concentric rings in the disk around HIP73145. This is one of the rare cases where multiple components are necessary to fit the SED and are also detected in scattered light. The presence of such ring structures somewhat questions the nature of the object as a pure debris disk, but the gas and dust content would presumably offer sufficient explanations for such structures to form., Comment: 14 pages, 14 figures
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- 2017
17. Eccentricity in planetary systems and the role of binarity: Sample definition, initial results, and the system of HD 211847
- Author
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Graeme Salter, Dino Mesa, Philippe Thebault, C. Moutou, Arthur Vigan, Silvano Desidera, Alice Zurlo, 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, and 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)
- Subjects
Outer planets ,Binary number ,FOS: Physical sciences ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,Planet ,0103 physical sciences ,Astrophysics::Solar and Stellar Astrophysics ,010303 astronomy & astrophysics ,planetary systems ,Solar and Stellar Astrophysics (astro-ph.SR) ,Astrophysics::Galaxy Astrophysics ,Physics ,Earth and Planetary Astrophysics (astro-ph.EP) ,010308 nuclear & particles physics ,techniques: high angular resolution ,Astronomy and Astrophysics ,Planetary system ,binaries: visual ,Exoplanet ,Radial velocity ,Stars ,Astrophysics - Solar and Stellar Astrophysics ,Space and Planetary Science ,Astrophysics::Earth and Planetary Astrophysics ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,Astrophysics - Earth and Planetary Astrophysics - Abstract
We explore the multiplicity of exoplanet host stars with high-resolution images obtained with VLT/SPHERE. Two different samples of systems were observed: one containing low-eccentricity outer planets, and the other containing high-eccentricity outer planets. We find that 10 out of 34 stars in the high-eccentricity systems are members of a binary, while the proportion is 3 out of 27 for circular systems. Eccentric-exoplanet hosts are, therefore, significantly more likely to have a stellar companion than circular-exoplanet hosts. The median magnitude contrast over the 68 data sets is 11.26 and 9.25, in H and K, respectively, at 0.30 arcsec. The derived detection limits reveal that binaries with separations of less than 50au are rarer for exoplanet hosts than for field stars. Our results also imply that the majority of high-eccentricity planets are not embedded in multiple stellar systems (24 out of 34), since our detection limits exclude the presence of a stellar companion. We detect the low-mass stellar companions of HD 7449 and HD 211847, both members of our high-eccentricity sample. HD 7449B was already detected by Rodigas et al (2016) and our independent observation is in agreement with this earlier work. HD 211847's substellar companion, previously detected by the radial velocity method, is actually a low-mass star seen face-on. The role of stellar multiplicity in shaping planetary systems is confirmed by this work, although it does not appear as the only source of dynamical excitation., Comment: A&A accepted, Dec 2016
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- 2017
18. RESOLVING THE PLANET-HOSTING INNER REGIONS OF THE LkCa 15 DISK
- Author
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Gael Chauvin, Johan Olofsson, Alice Zurlo, Dino Mesa, Thomas Henning, Carsten Dominik, Anthony Boccaletti, Mickael Bonnefoy, J. Lannier, François Ménard, Antonio Garufi, Sebastian Daemgen, Markus Feldt, E. Sissa, Raffaele Gratton, Christian Thalmann, N. Engler, Markus Janson, Anne-Marie Lagrange, H. M. Schmid, H. Le Coroller, Myriam Benisty, Silvano Desidera, Gijs D. Mulders, Michael R. Meyer, Christophe Pinte, Graeme Salter, Maud Langlois, Sascha P. Quanz, R. Ligi, Arthur Vigan, 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), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), 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), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, 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), Observatoire de Haute-Provence (OHP), Institut Pythéas (OSU PYTHEAS), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut de Recherche pour le Développement (IRD), Joseph Louis LAGRANGE (LAGRANGE), Université Nice Sophia Antipolis (... - 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, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), GDFSuez, Laboratoire Franco-Chilien d'Astronomie (LFCA), 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, 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), 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 pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Centre National de la Recherche Scientifique (CNRS), Université Nice Sophia Antipolis (1965 - 2019) (UNS), 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), 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], 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), 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), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich), 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), 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), 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), 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), 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), Low Energy Astrophysics (API, FNWI), 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), and Centre National de la Recherche Scientifique (CNRS)-Universidad de Concepción [Chile]-Pontificia Universidad Católica de Chile (UC)-Universidad de Chile-Institut national des sciences de l'Univers (INSU - CNRS)
- Subjects
Earth and Planetary Astrophysics (astro-ph.EP) ,Physics ,Brightness ,Scattering ,Polarimetry ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,01 natural sciences ,010309 optics ,Stars ,Astrophysics - Solar and Stellar Astrophysics ,Space and Planetary Science ,Planet ,0103 physical sciences ,Substructure ,Surface brightness ,Astrophysics::Earth and Planetary Astrophysics ,Protoplanet ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,010303 astronomy & astrophysics ,Solar and Stellar Astrophysics (astro-ph.SR) ,Astrophysics::Galaxy Astrophysics ,Astrophysics - Earth and Planetary Astrophysics - Abstract
LkCa 15 hosts a pre-transitional disk as well as at least one accreting protoplanet orbiting in its gap. Previous disk observations have focused mainly on the outer disk, which is cleared inward of ~50 au. The planet candidates, on the other hand, reside at orbital radii around 15 au, where disk observations have been unreliable until recently. Here we present new J-band imaging polarimetry of LkCa 15 with SPHERE IRDIS, yielding the most accurate and detailed scattered-light images of the disk to date down to the planet-hosting inner regions. We find what appear to be persistent asymmetric structures in the scattering material at the location of the planet candidates, which could be responsible at least for parts of the signals measured with sparse-aperture masking. These images further allow us to trace the gap edge in scattered light at all position angles and search the inner and outer disks for morphological substructure. The outer disk appears smooth with slight azimuthal variations in polarized surface brightness, which may be due to shadowing from the inner disk or a two-peaked polarized phase function. We find that the near-side gap edge revealed by polarimetry matches the sharp crescent seen in previous ADI imaging very well. Finally, the ratio of polarized disk to stellar flux is more than six times larger in J-band than in the RI bands., 6 pages, 4 figures, 1 table; accepted for publication in ApJ Letters
- Published
- 2016
19. Azimuthal asymmetries in the debris disk around HD61005 A massive collision of planetesimals?
- Author
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Anne-Marie Lagrange, Markus Janson, C. Thalmann, Dino Mesa, Johan Olofsson, D. Rouan, Th. Henning, R. G. Gratton, Andreas Bazzon, Graeme Salter, J. L. Beuzit, Carsten Dominik, Claudio Caceres, Christophe Pinte, Henning Avenhaus, Matthias R. Schreiber, Sascha P. Quanz, Amelia Bayo, J. Lannier, M. Feldt, Simon Casassus, Maud Langlois, Julien Milli, Gael Chauvin, Esther Buenzli, Anthony Boccaletti, Anne-Lise Maire, Hector Canovas, Arthur Vigan, J. C. Augereau, Matthias Samland, Attila Moór, Silvano Desidera, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), 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), Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), 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), Laboratoire Franco-Chilien d'Astronomie (LFCA), 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, 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), Low Energy Astrophysics (API, FNWI), 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), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich), 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), 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), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), 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), and 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]
- Subjects
Physics ,Debris disk ,Planetesimal ,010308 nuclear & particles physics ,media_common.quotation_subject ,Astronomy and Astrophysics ,Context (language use) ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,01 natural sciences ,Debris ,13. Climate action ,Space and Planetary Science ,Planet ,0103 physical sciences ,Spectral energy distribution ,Terrestrial planet ,Astrophysics::Solar and Stellar Astrophysics ,Astrophysics::Earth and Planetary Astrophysics ,Eccentricity (behavior) ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,media_common - Abstract
Context. Debris disks offer valuable insights into the latest stages of circumstellar disk evolution, and can possibly help us to trace the outcomes of planetary formation processes. In the age range 10 to 100 Myr, most of the gas is expected to have been removed from the system, giant planets (if any) must have already been formed, and the formation of terrestrial planets may be on-going. Pluto-sized planetesimals, and their debris released in a collisional cascade, are under their mutual gravitational influence, which may result into non-axisymmetric structures in the debris disk. Aims: High angular resolution observations are required to investigate these effects and constrain the dynamical evolution of debris disks. Furthermore, multi-wavelength observations can provide information about the dust dynamics by probing different grain sizes. Methods: Here we present new VLT/SPHERE and ALMA observations of the debris disk around the 40 Myr-old solar-type star HD 61005. We resolve the disk at unprecedented resolution both in the near-infrared (in scattered and polarized light) and at millimeter wavelengths. We perform a detailed modeling of these observations, including the spectral energy distribution. Results: Thanks to the new observations, we propose a solution for both the radial and azimuthal distribution of the dust grains in the debris disk. We find that the disk has a moderate eccentricity (e ~ 0.1) and that the dust density is two times larger at the pericenter compared to the apocenter. Conclusions: With no giant planets detected in our observations, we investigate alternative explanations besides planet-disk interactions to interpret the inferred disk morphology. We postulate that the morphology of the disk could be the consequence of a massive collision between ~1000 km-sized bodies at ~61 au. If this interpretation holds, it would put stringent constraints on the formation of massive planetesimals at large distances from the star. Based on observations made with ESO Telescopes at the Paranal Observatory under programs ID 095.C-0298 and 095.C-0273. Based on Herschel observations, OBSIDs: 1342270977, 1342270978, 1342270979, 1342270989, and 1342255147. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.The reduced images as FITS files, and data of Fig. 1 are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/591/A108
- Published
- 2016
20. The SPHERE view of the planet-forming disk around HD 100546
- Author
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Thomas Henning, Francois Menard, Andreas Bazzon, Antonio Garufi, Henning Avenhaus, E. Sissa, Markus Kasper, Anthony K. Cheetham, Gijs D. Mulders, Markus Janson, Raffaele Gratton, Jean-Charles Augereau, Francois Wildi, Graeme Salter, Anne-Lise Maire, Dino Mesa, Anne-Marie Lagrange, Tomas Stolker, Esther Buenzli, Carsten Dominik, Wolfgang Brandner, Markus Feldt, Myriam Benisty, Silvano Desidera, Maud Langlois, Clément Perrot, Gael Chauvin, David Mouillet, Bruno Lopez, Sascha P. Quanz, Anthony Boccaletti, Christian Ginski, Arthur Vigan, Mickael Bonnefoy, Raphael Galicher, Christophe Pinte, J. Lannier, Alice Zurlo, S. Peretti, Michael Meyer, Hans Martin Schmid, M. Cudel, Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), 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, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), 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), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Joseph Louis LAGRANGE (LAGRANGE), Université Nice Sophia Antipolis (... - 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), Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, GDFSuez, Laboratoire Franco-Chilien d'Astronomie (LFCA), 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, 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), ESO, Physics Department [Garching], Technische Universität Munchen - Université Technique de Munich [Munich, Allemagne] (TUM)-Technische Universität Munchen - Université Technique de Munich [Munich, Allemagne] (TUM), aucun, IDELE, University of Geneva, Genève, Low Energy Astrophysics (API, FNWI), 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), Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-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), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich), 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), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), 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), 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), Technical University of Munich (TUM)-Technical University of Munich (TUM), 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), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université Nice Sophia Antipolis (1965 - 2019) (UNS), 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], and Institut de l'élevage (IDELE)
- Subjects
Physics ,Earth and Planetary Astrophysics (astro-ph.EP) ,Brightness ,Photon ,010504 meteorology & atmospheric sciences ,Be star ,Scattering ,Conjunction (astronomy) ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,01 natural sciences ,Astrophysics - Solar and Stellar Astrophysics ,Space and Planetary Science ,Planet ,0103 physical sciences ,Astrophysics::Earth and Planetary Astrophysics ,Adaptive optics ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,010303 astronomy & astrophysics ,Image resolution ,Solar and Stellar Astrophysics (astro-ph.SR) ,Astrophysics::Galaxy Astrophysics ,0105 earth and related environmental sciences ,Astrophysics - Earth and Planetary Astrophysics - Abstract
We image with unprecedented spatial resolution and sensitivity disk features that could be potential signs of planet-disk interaction. Two companion candidates have been claimed in the disk around the young Herbig Ae/Be star HD100546. Thus, this object serves as an excellent target for our investigation of the natal environment of giant planets. We exploit the power of extreme adaptive optics operating in conjunction with the new high-contrast imager SPHERE to image HD100546 in scattered light. We obtain the first polarized light observations of this source in the visible (with resolution as fine as 2 AU) and new H and K band total intensity images that we analyze with the Pynpoint package. The disk shows a complex azimuthal morphology, where multiple scattering of photons most likely plays an important role. High brightness contrasts and arm-like structures are ubiquitous in the disk. A double-wing structure (partly due to ADI processing) resembles a morphology newly observed in inclined disks. Given the cavity size in the visible (11 AU), the CO emission associated to the planet candidate 'c' might arise from within the circumstellar disk. We find an extended emission in the K band at the expected location of 'b'. The surrounding large-scale region is the brightest in scattered light. There is no sign of any disk gap associated to 'b'., Accepted by A&A. 13 pages, 5 figures
- Published
- 2016
21. Secondary eclipse observations for seven hot-Jupiters from the Anglo-Australian Telescope
- Author
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Graeme Salter, C. G. Tinney, Daniel Bayliss, Joseph E. Rodriguez, Lucyna Kedziora-Chudczer, Jeremy Bailey, George Zhou, University of Newcastle [Callaghan, Australia] (UoN), 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), Institut des Sciences Moléculaires de Marseille (ISM2), Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), University of Newcastle [Australia] (UoN), and Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Institut de Chimie du CNRS (INC)
- Subjects
Brightness ,010504 meteorology & atmospheric sciences ,Infrared ,FOS: Physical sciences ,Context (language use) ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,law.invention ,Telescope ,law ,Planet ,0103 physical sciences ,Hot Jupiter ,Astrophysics::Solar and Stellar Astrophysics ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,0105 earth and related environmental sciences ,Eclipse ,Earth and Planetary Astrophysics (astro-ph.EP) ,Physics ,Astronomy ,Astronomy and Astrophysics ,13. Climate action ,Space and Planetary Science ,[SDU]Sciences of the Universe [physics] ,Brightness temperature ,Astrophysics::Earth and Planetary Astrophysics ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,Astrophysics - Earth and Planetary Astrophysics - Abstract
We report detections and constraints for the near infrared Ks band secondary eclipses of seven hot-Jupiters using the IRIS2 infrared camera on the Anglo-Australian Telescope. Eclipses in the Ks band for WASP-18b and WASP-36b have been measured for the first time. We also present new measurements for the eclipses of WASP-4b, WASP-5b, and WASP-46b, as well as upper limits for the eclipse depths of WASP-2b and WASP-76b. In particular, two full eclipses of WASP-46b were observed, allowing us to demonstrate the repeatability of our observations via independent analyses on each eclipse. Significant numbers of eclipse depths for hot-Jupiters have now been measured in both Ks and the four Spitzer IRAC bandpasses. We discuss these measurements in the context of the broadband colours and brightness temperatures of the hot-Jupiter atmosphere distribution. Specifically, we re-examine the proposed temperature dichotomy between the most irradiated, and mildly irradiated planets. We find no evidence for multiple clusters in the brightness temperature - equilibrium temperature distributions in any of these bandpasses, suggesting a continuous distribution of heat re-emission and circulation characteristics for these planets., 22 pages, accepted for publication in MNRAS
- Published
- 2015
22. SWIFT observations of the Arp 147 ring galaxy system
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Graeme Salter, Timothy Goodsall, Roger L. Davies, Matthias Tecza, Fraser Clarke, Niranjan Thatte, Lisa Fogarty, Susan A. Kassin, and Ryan C. W. Houghton
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Physics ,education.field_of_study ,Stellar mass ,Star formation ,Metallicity ,Population ,Astronomy and Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Ring (chemistry) ,Galaxy ,Space and Planetary Science ,Bulge ,Ring galaxy ,education ,Astrophysics::Galaxy Astrophysics - Abstract
We present observations of Arp 147, a galaxy system comprising a collisionally-created ring galaxy and an early-type galaxy, using the Oxford SWIFT integral field spectrograph (IFS) at the 200-inch Hale telescope. We derive spatially resolved kinematics from the IFS data and use these to study the interaction between the two galaxies. We find the edge-to-edge expansion velocity of the ring is 225 +/- 8 km/s, implying an upper limit on the timescale for the collision of 50 Myrs. We also calculate that the angle of impact for the collision is between 33 degrees-54 degrees, where 0 degrees would imply a perpendicular collision. The ring galaxy is strongly star-forming with the star formation likely to have been triggered by the collision between the two galaxies. We measure some key physical parameters in an integrated and spatially resolved manner for the ring galaxy. Using observed B-I colours and the H-alpha equivalent widths, we conclude that two stellar components (a young and an old population) are required to simultaneously match both observed quantities. We constrain the age range, light and mass fractions of the young star formation in the ring, finding a modest age range, a light fraction of less than a third, and a negligible (
- Published
- 2011
23. Resolving faint structures in the debris disk around TWA 7
- Author
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Francois Menard, Maud Langlois, Markus Janson, R. G. van Holstein, R. G. Gratton, Philippe Feautrier, Claudio Caceres, Wolfgang Brandner, D. Mawet, Graeme Salter, Th. Henning, E. Sissa, Amelia Bayo, Dino Mesa, M. Feldt, A. Roux, A. Pavlov, C. A. Grady, Gael Chauvin, Silvano Desidera, C. Perrot, David Mouillet, J. Lannier, Ch. Ginski, Philippe Thébault, Johan Olofsson, Thibaut Moulin, A-L. Maire, D. Le Mignant, A-M. Lagrange, T. Schmidt, Matthias R. Schreiber, C. Lazzoni, R. Ligi, Julien Milli, N. Godoy, C. Thalmann, Stephen Durkan, P. Rabou, Janis Hagelberg, Christophe Pinte, Quentin Kral, Anthony Boccaletti, L. Abe, Esther Buenzli, N. Engler, Hector Canovas, Arthur Vigan, Gérard Rousset, J. C. Augereau, Joshua E. Schlieder, S. Peretti, Ruben Asensio-Torres, and Mickael Bonnefoy
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Physics ,Debris disk ,Spiral galaxy ,010504 meteorology & atmospheric sciences ,instrumentation: polarimeters ,Astronomy and Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Position angle ,circumstellar matter ,01 natural sciences ,Stars ,instrumentation: high angular resolution ,Space and Planetary Science ,Planet ,0103 physical sciences ,Astrophysics::Solar and Stellar Astrophysics ,Spectral energy distribution ,Astrophysics::Earth and Planetary Astrophysics ,Low Mass ,010303 astronomy & astrophysics ,Planetary mass ,Astrophysics::Galaxy Astrophysics ,0105 earth and related environmental sciences - Abstract
Context. Debris disks are the intrinsic by-products of the star and planet formation processes. Most likely due to instrumental limitations and their natural faintness, little is known about debris disks around low mass stars, especially when it comes to spatially resolved observations. Aims. We present new VLT/SPHERE IRDIS dual-polarization imaging (DPI) observations in which we detect the dust ring around the M2 spectral type star TWA 7. Combined with additional angular differential imaging observations we aim at a fine characterization of the debris disk and setting constraints on the presence of low-mass planets. Methods. We modeled the SPHERE DPI observations and constrain the location of the small dust grains, as well as the spectral energy distribution of the debris disk, using the results inferred from the observations, and performed simple N-body simulations. Results. We find that the dust density distribution peaks at ~0.72′′ (25 au), with a very shallow outer power-law slope, and that the disk has an inclination of ~13° with a position angle of ~91° east of north. We also report low signal-to-noise ratio detections of an outer belt at a distance of ~1.5′′ (~52 au) from the star, of a spiral arm in the southern side of the star, and of a possible dusty clump at 0.11′′. These findings seem to persist over timescales of at least a year. Using the intensity images, we do not detect any planets in the close vicinity of the star, but the sensitivity reaches Jovian planet mass upper limits. We find that the SED is best reproduced with an inner disk at ~0.2′′ (~7 au) and another belt at 0.72′′ (25 au). Conclusions. We report the detections of several unexpected features in the disk around TWA 7. A yet undetected 100M⊕ planet with a semi-major axis at 20−30 au could possibly explain the outer belt as well as the spiral arm. We conclude that stellar winds are unlikely to be responsible for the spiral arm.
- Published
- 2018
24. High-contrast imaging of Sirius A with VLT/SPHERE: looking for giant planets down to one astronomical unit
- Author
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C. Moutou, Graeme Salter, Cecile Gry, Dino Mesa, Arthur Vigan, D. Homeier, F. Allard, 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), Canada-France-Hawaii Telescope Corporation (CFHT), National Research Council of Canada (NRC)-Centre National de la Recherche Scientifique (CNRS)-University of Hawai'i [Honolulu] (UH), 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), and Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
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Physics ,Earth and Planetary Astrophysics (astro-ph.EP) ,Very Large Telescope ,Sirius ,Astronomical unit ,Astronomy ,White dwarf ,FOS: Physical sciences ,Astronomy and Astrophysics ,High contrast imaging ,Astrophysics ,Planetary system ,Exoplanet ,13. Climate action ,Space and Planetary Science ,Planet ,Astrophysics - Instrumentation and Methods for Astrophysics ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,Astrophysics - Earth and Planetary Astrophysics - Abstract
Sirius has always attracted a lot of scientific interest, especially after the discovery of a companion white dwarf at the end of the 19th century. Very early on, the existence of a potential third body was put forward to explain some of the observed properties of the system. We present new coronagraphic observations obtained with VLT/SPHERE that explore, for the very first time, the innermost regions of the system down to 0.2" (0.5 AU) from Sirius A. Our observations cover the near-infrared from 0.95 to 2.3 $\mu$m and they offer the best on-sky contrast ever reached at these angular separations. After detailing the steps of our SPHERE/IRDIFS data analysis, we present a robust method to derive detection limits for multi-spectral data from high-contrast imagers and spectrographs. In terms of raw performance, we report contrasts of 14.3 mag at 0.2", ~16.3 mag in the 0.4-1.0" range and down to 19 mag at 3.7". In physical units, our observations are sensitive to giant planets down to 11 $M_{Jup}$ at 0.5 AU, 6-7 $M_{Jup}$ in the 1-2 AU range and ~4 $M_{Jup}$ at 10 AU. Despite the exceptional sensitivity of our observations, we do not report the detection of additional companions around Sirius A. Using a Monte Carlo orbital analysis, we show that we can reject, with about 50% probability, the existence of an 8 $M_{Jup}$ planet orbiting at 1 AU. In addition to the results presented in the paper, we provide our SPHERE/IFS data reduction pipeline at http://people.lam.fr/vigan.arthur/ under the MIT license., Comment: 16 pages, 10 figures, accepted for publication in MNRAS
- Published
- 2015
25. The Pan-Pacific Planet Search III: Five companions orbiting giant stars
- Author
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Graeme Salter, Christoph Bergmann, R. P. Butler, C. G. Tinney, Lan Wang, Robert A. Wittenmyer, John Asher Johnson, 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), 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
010504 meteorology & atmospheric sciences ,media_common.quotation_subject ,Brown dwarf ,FOS: Physical sciences ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,Planet ,0103 physical sciences ,Astrophysics::Solar and Stellar Astrophysics ,Eccentricity (behavior) ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,0105 earth and related environmental sciences ,media_common ,Physics ,Earth and Planetary Astrophysics (astro-ph.EP) ,Giant planet ,Astronomy ,Astronomy and Astrophysics ,Planetary system ,Giant star ,Radial velocity ,Orbit ,13. Climate action ,Space and Planetary Science ,[SDU]Sciences of the Universe [physics] ,Astrophysics::Earth and Planetary Astrophysics ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,Astrophysics - Earth and Planetary Astrophysics - Abstract
We report a new giant planet orbiting the K giant HD 155233, as well as four stellar-mass companions from the Pan-Pacific Planet Search, a southern hemisphere radial velocity survey for planets orbiting nearby giants and subgiants. We also present updated velocities and a refined orbit for HD 47205b (7 CMa b), the first planet discovered by this survey. HD 155233b has a period of 885$\pm$63 days, eccentricity e=0.03$\pm$0.20, and m sin i=2.0$\pm$0.5 M_jup. The stellar-mass companions range in m sin i from 0.066 M_sun to 0.33 M_sun. Whilst HD 104358B falls slightly below the traditional 0.08 M_sun hydrogen-burning mass limit, and is hence a brown dwarf candidate, we estimate only a 50% a priori probability of a truly substellar mass., Comment: Accepted for publication in MNRAS
- Published
- 2015
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26. A narrow, edge-on disk resolved around HD 106906 with SPHERE
- Author
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Matthias Samland, Thomas Henning, Lyu Abe, S. Peretti, Anne-Lise Maire, Hervé Beust, H. Le Coroller, F. Madec, Clément Perrot, Raphael Galicher, Johan Olofsson, Gael Chauvin, Mickael Bonnefoy, Christian Thalmann, Cyril Petit, A-M. Lagrange, Maud Langlois, Markus Janson, Dino Mesa, Graeme Salter, E. Sissa, Julien Girard, J. L. Beuzit, L. Weber, Wolfgang Brandner, Raffaele Gratton, Matthew A. Kenworthy, Julien Milli, J. Lannier, Silvano Desidera, François Ménard, Markus Feldt, D. Perret, C. Soenke, Anthony Boccaletti, P. Rabou, David Mouillet, Esther Buenzli, Vanessa P. Bailey, Anthony Cheetham, Arthur Vigan, Zahed Wahhaj, Surace, Christian, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), 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), INAF - Osservatorio Astronomico di Padova (OAPD), Istituto Nazionale di Astrofisica (INAF), European Southern Observatory [Santiago] (ESO), European Southern Observatory (ESO), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, Steward Observatory, University of Arizona, 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), Centre scientifique et Technique Jean Feger (CSTJF), TOTAL FINA ELF, Sterrewacht Leiden, Universiteit Leiden [Leiden], Institute for Astronomy [Zürich], Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), Geneva Observatory, Université de Genève = University of Geneva (UNIGE), Department of Astronomy, Stockholm University, Observatoire de Haute-Provence (OHP), Institut Pythéas (OSU PYTHEAS), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Centre National de la Recherche Scientifique (CNRS), 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), De la Molécule aux Nanos-objets : Réactivité, Interactions et Spectroscopies (MONARIS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), ESO, Physics Department [Garching], Technische Universität Munchen - Université Technique de Munich [Munich, Allemagne] (TUM)-Technische Universität Munchen - Université Technique de Munich [Munich, Allemagne] (TUM), European Synchrotron Radiation Facility (ESRF), Centre de Recherche en Acquisition et Traitement de l'Image pour la Santé (CREATIS), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Université Jean Monnet - Saint-Étienne (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Institut de Planétologie et d'Astrophysique de Grenoble [2011-2019] (IPAG [2011-2019]), Observatoire des Sciences de l'Univers de Grenoble [1985-2015] (OSUG [1985-2015]), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology [2007-2019] (Grenoble INP [2007-2019])-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology [2007-2019] (Grenoble INP [2007-2019])-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), 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), Instituto de Fisica y Astronomia, ICM nucleus on protoplanetary disks, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Franco-Chilien d'Astronomie (LFCA), 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), Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève (UNIGE), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut de Recherche pour le Développement (IRD), 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)-Centre National de la Recherche Scientifique (CNRS), ONERA - The French Aerospace Lab [Châtillon], Université Paris Saclay (COmUE)-ONERA, Université Joseph Fourier - Grenoble 1 (UJF), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Laboratoire 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), 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), TOTAL-Scientific and Technical Center Jean Féger (CSTJF), University of Geneva [Switzerland], 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), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Technical University of Munich (TUM)-Technical University of Munich (TUM), Université Jean Monnet [Saint-Étienne] (UJM)-Hospices Civils de Lyon (HCL)-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)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble [1985-2015] (OSUG [1985-2015]), Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology [2007-2019] (Grenoble INP [2007-2019])-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-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)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology [2007-2019] (Grenoble INP [2007-2019])-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES), Centre National de la Recherche Scientifique (CNRS)-Universidad de Concepción [Chile]-Pontificia Universidad Católica de Chile (UC)-Universidad de Chile-Institut national des sciences de l'Univers (INSU - CNRS), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Universiteit Leiden, Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Jean Monnet - Saint-Étienne (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-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)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), 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), Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA), ONERA, and université J.Fourier
- Subjects
Brightness ,010504 meteorology & atmospheric sciences ,HD 106906 ,FOS: Physical sciences ,Astrophysics ,01 natural sciences ,[SDU] Sciences of the Universe [physics] ,Planet ,0103 physical sciences ,PLANETARY SYSTEMS ,Astrophysics::Solar and Stellar Astrophysics ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,Solar and Stellar Astrophysics (astro-ph.SR) ,0105 earth and related environmental sciences ,Physics ,Earth and Planetary Astrophysics (astro-ph.EP) ,Debris disk ,Spectrometer ,Plane (geometry) ,HIGH ANGULAR RESOLUTION ,Astronomy and Astrophysics ,Planetary system ,[PHYS.PHYS.PHYS-SPACE-PH]Physics [physics]/Physics [physics]/Space Physics [physics.space-ph] ,Orbit ,Astrophysics - Solar and Stellar Astrophysics ,Radiation pressure ,13. Climate action ,Space and Planetary Science ,[SDU]Sciences of the Universe [physics] ,[SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic ,Astrophysics::Earth and Planetary Astrophysics ,[PHYS.ASTR] Physics [physics]/Astrophysics [astro-ph] ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,Astrophysics - Earth and Planetary Astrophysics - Abstract
HD~106906AB is so far the only young binary system around which a planet has been imaged and a debris disk evidenced thanks to a strong IR excess. As such, it represents a unique opportunity to study the dynamics of young planetary systems. We aim at further investigating the close (tens of au scales) environment of the HD~106906AB system. We used the extreme AO fed, high contrast imager SPHERE recently installed on the VLT to observe HD~106906. Both the IRDIS imager and the Integral Field Spectrometer were used. We discovered a very inclined, ring-like disk at a distance of 65~au from the star. The disk shows a strong brightness asymmetry with respect to its semi-major axis. It shows a smooth outer edge, compatible with ejection of small grains by the stellar radiation pressure. We show furthermore that the planet's projected position is significantly above the disk's PA. Given the determined disk inclination, it is not excluded though that the planet could still orbit within the disk plane if at a large separation (2000--3000 au). We identified several additional point sources in the SPHERE/IRDIS field-of-view, that appear to be background objects. We compare this system with other debris disks sharing similarities, and we briefly discuss the present results in the framework of dynamical evolution., Comment: 7 pages, 6 figures, accepted by Astronomy & Astrophysics
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- 2015
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27. Comparing online and traditional teaching – a different approach
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Graeme Salter
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Computer based learning ,Knowledge management ,Error-driven learning ,Computer Networks and Communications ,Computer science ,business.industry ,Teaching method ,Educational technology ,Library and Information Sciences ,Synchronous learning ,Human–computer interaction ,Active learning ,Online teaching ,Learning methods ,business - Abstract
Rather than attempt to measure the effectiveness of online teaching by comparison with some non‐existent traditional method, this paper attempts to determine the conditions that promote learning and examine if these can be provided in an online environment. In this case, learning is viewed as a path to wisdom rather than simply having knowledge or the ability to apply knowledge. After examining the role of technology related to conditions for learning, the paper suggests that technology has the potential to enhance and transform teaching, but it can also be used inappropriately or in ways that actually interfere with learning. The real question is not whether effective learning can occur online, but rather how this can be most appropriately achieved?
- Published
- 2003
28. Direct Detection of Nearby Habitable Zone Planets Using Slicer Based Integral Field Spectrographs and EPICS on the E-ELT
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Markus Kasper, Graeme Salter, Fraser Clarke, Matthias Tecza, and Niranjan Thatte
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Physics ,business.industry ,Astronomy and Astrophysics ,Speckle noise ,Exoplanet ,Speckle pattern ,Integral field spectrograph ,Optics ,Space and Planetary Science ,Planet ,Adaptive optics ,Extremely large telescope ,business ,Circumstellar habitable zone - Abstract
Early design studies for the future Exo-Planet Imaging Camera and Specrotgraph (EPICS) on the European Extremely Large Telescope (E-ELT) show the ability to probe the region of super-Earths in the habitable zone of stars within 5pc (including Gilese 581d). However, these planets will be lost to us if the correct choice of integral field spectrograph (IFS) technology is not selected for such an instrument the ability to fit and remove the speckle noise that remains is crucial to reaching these contrasts.We conclusively demonstrate, though the use of an experimental setup producing an artificial speckle, that slicer based IFSs and post-processing using spectral deconvolution can achieve speckle rejection factors exceeding 103. Contrary to popular belief, we do not find any evidence that this choice of IFS technology limits the achievable contrast. Coupled with extreme adaptive optics and high performance coronographs, a slicer based integral field spectrograph could achieve contrasts exceeding 109, enabling these super-Earths to be detected in the habitable zone of nearby stars, making it an attractive option for the next generation of instruments being designed for the direct detection of extra solar planets.
- Published
- 2012
29. Ks band secondary eclipses of WASP-19b and WASP-43b with the Anglo-Australian Telescope
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C. G. Tinney, Daniel Bayliss, Jeremy Bailey, Lucyna Kedziora-Chudczer, Graeme Salter, and G. Zhou
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Earth and Planetary Astrophysics (astro-ph.EP) ,Physics ,Arc (geometry) ,Telescope ,Space and Planetary Science ,law ,FOS: Physical sciences ,Astronomy ,Astronomy and Astrophysics ,Astrophysics ,law.invention ,Astrophysics - Earth and Planetary Astrophysics - Abstract
We report new Ks band secondary eclipse observations for the hot-Jupiters WASP-19b and WASP-43b. Using the IRIS2 infrared camera on the Anglo-Australian Telescope (AAT), we measured significant secondary eclipses for both planets, with depths of 0.287 -0.020/+0.020% and 0.181 -0.027/+0.027% for WASP-19b and WASP-43b respectively. We compare the observations to atmosphere models from the VSTAR line-by-line radiative transfer code, and examine the effect of C/O abundance, top layer haze, and metallicities on the observed spectra. We performed a series of signal injection and recovery exercises on the observed light curves to explore the detection thresholds of the AAT+IRIS2 facility. We find that the optimal photometric precision is achieved for targets brighter than Kmag = 9, for which eclipses as shallow as 0.05% are detectable at >5 sigma significance., Accepted for publication in MNRAS, 13 pages, 10 figures
- Published
- 2014
30. GJ 832c: A Super-Earth in the Habitable Zone
- Author
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C. G. Tinney, Graeme Salter, Matías R. Díaz, Mikko Tuomi, R. P. Butler, Jeffrey D. Crane, S. A. Schectman, Guillem Anglada-Escudé, Simon J. O'Toole, Robert A. Wittenmyer, Pamela Arriagada, Jonathan P. Marshall, Dante Minniti, James S. Jenkins, Hugh R. A. Jones, Duncan J. Wright, Jeremy Bailey, B. D. Carter, Ian B. Thompson, and Jonathan Horner
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Physics ,Earth and Planetary Astrophysics (astro-ph.EP) ,Solar System ,Super-Earth ,Giant planet ,FOS: Physical sciences ,Astronomy and Astrophysics ,Planetary system ,Astrobiology ,Atmosphere ,Jupiter ,Space and Planetary Science ,Planet ,Astrophysics::Earth and Planetary Astrophysics ,Circumstellar habitable zone ,Astrophysics - Earth and Planetary Astrophysics - Abstract
We report the detection of GJ 832c, a super-Earth orbiting near the inner edge of the habitable zone of GJ 832, an M dwarf previously known to host a Jupiter analog in a nearly-circular 9.4-year orbit. The combination of precise radial-velocity measurements from three telescopes reveals the presence of a planet with a period of 35.68+/-0.03 days and minimum mass (m sin i) of 5.4+/-1.0 Earth masses. GJ 832c moves on a low-eccentricity orbit (e=0.18+/-0.13) towards the inner edge of the habitable zone. However, given the large mass of the planet, it seems likely that it would possess a massive atmosphere, which may well render the planet inhospitable. Indeed, it is perhaps more likely that GJ 832c is a "super-Venus," featuring significant greenhouse forcing. With an outer giant planet and an interior, potentially rocky planet, the GJ 832 planetary system can be thought of as a miniature version of our own Solar system., Comment: Accepted for publication in ApJ
- Published
- 2014
31. The Anglo-Australian Planet Search. XXIII. Two New Jupiter Analogs
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R. P. Butler, Brad D. Carter, Mikko Tuomi, Jeremy Bailey, Graeme Salter, Simon J. O'Toole, Duncan J. Wright, Hugh R. A. Jones, F. Elliott Koch, C. G. Tinney, Robert A. Wittenmyer, and Jonathan Horner
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Physics ,Earth and Planetary Astrophysics (astro-ph.EP) ,Solar System ,education.field_of_study ,Population ,Astronomy ,Minimum mass ,FOS: Physical sciences ,Astronomy and Astrophysics ,Planetary system ,Orbital period ,Jupiter ,Space and Planetary Science ,Planet ,education ,Astrophysics - Earth and Planetary Astrophysics - Abstract
We report the discovery of two long-period giant planets from the Anglo-Australian Planet Search. HD 154857c is in a multiple-planet system, while HD 114613b appears to be solitary. HD 114613b has an orbital period P=10.5 years, and a minimum mass m sin i of 0.48 Jupiter masses; HD 154857c has P=9.5 years and m sin i=2.6 Jupiter masses. These new data confirm the planetary nature of the previously unconstrained long-period object in the HD 154857 system. We have performed detailed dynamical stability simulations which show that the HD 154857 two-planet system is stable on timescales of at least 100 million years. These results highlight the continued importance of "legacy" surveys with long observational baselines; these ongoing campaigns are critical for determining the population of Jupiter analogs, and hence of those planetary systems with architectures most like our own Solar system., Comment: Accepted for publication in ApJ
- Published
- 2014
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32. A Detailed Analysis of the HD 73526 2:1 Resonant Planetary System
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Xianyu Tan, Simon J. O'Toole, Pamela Arriagada, Duncan J. Wright, Dante Minniti, Jeremy Bailey, Brad D. Carter, Jeffrey D. Crane, Robert A. Wittenmyer, Marco Aurelio Diaz, Ian B. Thompson, Hugh R. A. Jones, R. P. Butler, Jonathan Horner, S. A. Schectman, Man Hoi Lee, C. G. Tinney, and Graeme Salter
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Physics ,Earth and Planetary Astrophysics (astro-ph.EP) ,Amplitude ,Space and Planetary Science ,Planet ,Resonance ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Astrophysics::Earth and Planetary Astrophysics ,Planetary system ,Stability (probability) ,Astrophysics - Earth and Planetary Astrophysics - Abstract
We present six years of new radial-velocity data from the Anglo-Australian and Magellan Telescopes on the HD 73526 2:1 resonant planetary system. We investigate both Keplerian and dynamical (interacting) fits to these data, yielding four possible configurations for the system. The new data now show that both resonance angles are librating, with amplitudes of 40 degrees and 60 degrees, respectively. We then perform long-term dynamical stability tests to differentiate these solutions, which only differ significantly in the masses of the planets. We show that while there is no clearly preferred system inclination, the dynamical fit with i=90 degrees provides the best combination of goodness-of-fit and long-term dynamical stability., Accepted for publication in ApJ
- Published
- 2013
33. Forever alone? Testing single eccentric planetary systems for multiple companions
- Author
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C. G. Tinney, Graeme Salter, Duncan J. Wright, B. D. Carter, Robert A. Wittenmyer, Ji-Lin Zhou, Jonathan Horner, Jeremy Bailey, R. P. Butler, Songhu Wang, Simon J. O'Toole, and Hugh R. A. Jones
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Earth and Planetary Astrophysics (astro-ph.EP) ,Computer science ,media_common.quotation_subject ,Astronomy ,FOS: Physical sciences ,Astronomy and Astrophysics ,Orbital eccentricity ,Planetary system ,Stability (probability) ,Exoplanet ,Space and Planetary Science ,Planet ,Astrophysics::Earth and Planetary Astrophysics ,Eccentricity (behavior) ,media_common ,Astrophysics - Earth and Planetary Astrophysics - Abstract
Determining the orbital eccentricity of an extrasolar planet is critically important for understanding the system's dynamical environment and history. However, eccentricity is often poorly determined or entirely mischaracterized due to poor observational sampling, low signal-to-noise, and/or degeneracies with other planetary signals. Some systems previously thought to contain a single, moderate-eccentricity planet have been shown, after further monitoring, to host two planets on nearly-circular orbits. We investigate published apparent single-planet systems to see if the available data can be better fit by two lower-eccentricity planets. We identify nine promising candidate systems and perform detailed dynamical tests to confirm the stability of the potential new multiple-planet systems. Finally, we compare the expected orbits of the single- and double-planet scenarios to better inform future observations of these interesting systems., Accepted for publication in ApJS
- Published
- 2013
34. Fast and Slow Rotators in the Densest Environments: a SWIFT IFS study of the Coma Cluster
- Author
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Fraser Clarke, Graeme Salter, Francesco D'Eugenio, Nicholas Scott, M. Tecza, Ryan C. W. Houghton, L. M. R. Fogarty, N. Thatte, Roger L. Davies, and Timothy Goodsall
- Subjects
Physics ,education.field_of_study ,Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,010308 nuclear & particles physics ,Population ,Astronomy ,FOS: Physical sciences ,Astronomy and Astrophysics ,Coma (optics) ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,Virgo Cluster ,Galaxy ,Luminosity ,Space and Planetary Science ,0103 physical sciences ,Coma Cluster ,Mass segregation ,education ,010303 astronomy & astrophysics ,Galaxy cluster ,Astrophysics::Galaxy Astrophysics ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
We present integral-field spectroscopy of 27 galaxies in the Coma cluster observed with the Oxford SWIFT spectrograph, exploring the kinematic morphology-density relationship in a cluster environment richer and denser than any in the ATLAS3D survey. Our new data enables comparison of the kinematic morphology relation in three very different clusters (Virgo, Coma and Abell 1689) as well as to the field/group environment. The Coma sample was selected to match the parent luminosity and ellipticity distributions of the early-type population within a radius 15' (0.43 Mpc) of the cluster centre, and is limited to r' = 16 mag (equivalent to M_K = -21.5 mag), sampling one third of that population. From analysis of the lambda-ellipticity diagram, we find 15+-6% of early-type galaxies are slow rotators; this is identical to the fraction found in the field and the average fraction in the Virgo cluster, based on the ATLAS3D data. It is also identical to the average fraction found recently in Abell 1689 by D'Eugenio et al.. Thus it appears that the average slow rotator fraction of early type galaxies remains remarkably constant across many different environments, spanning five orders of magnitude in galaxy number density. However, within each cluster the slow rotators are generally found in regions of higher projected density, possibly as a result of mass segregation by dynamical friction. These results provide firm constraints on the mechanisms that produce early-type galaxies: they must maintain a fixed ratio between the number of fast rotators and slow rotators while also allowing the total early-type fraction to increase in clusters relative to the field. A complete survey of Coma, sampling hundreds rather than tens of galaxies, could probe a more representative volume of Coma and provide significantly stronger constraints, particularly on how the slow rotator fraction varies at larger radii., Comment: Accepted for publication in MNRAS
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- 2013
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35. Discovery of concentric broken rings at sub-arcsec separations in the HD 141569A gas-rich, debris disk with VLT/SPHERE
- Author
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Mickael Bonnefoy, A-L. Maire, Dino Mesa, J. Lannier, Wolfgang Brandner, Esther Buenzli, Antonio Garufi, Arnaud Sevin, David Mouillet, C. Perrot, Anthony Boccaletti, M. Carle, Valentin Christiaens, Pierre Baudoz, Johan Olofsson, J. L. Beuzit, O. Moeller-Nilsson, Raffaele Gratton, J. Péricaud, Arthur Vigan, Myriam Benisty, R. Galicher, Eric Pantin, Gael Chauvin, Julien Milli, Johan Mazoyer, Gérard Rousset, Sascha P. Quanz, Norbert Hubin, A-M. Lagrange, Anne Dutrey, Thierry Fusco, S. Peretti, Markus Feldt, E. Sissa, Enrico Giro, Jean-Charles Augereau, Julien Girard, Simon Casassus, J. de Boer, Silvano Desidera, E. Di Folco, P. Blanchard, François Ménard, Maud Langlois, D. Maurel, Graeme Salter, L. Weber, 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), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, 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), AMOR 2016, Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut de Mathématiques de Marseille (I2M), Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), ONERA - The French Aerospace Lab [Châtillon], ONERA-Université Paris Saclay (COmUE), European Synchrotron Radiation Facility (ESRF), 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), 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), Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Aix Marseille Université (AMU), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich), Unité de Catalyse et de Chimie du Solide - Site Artois (UCCS Artois), Université d'Artois (UA)-Université de Lille, Sciences et Technologies-Ecole Centrale de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Centre National de la Recherche Scientifique (CNRS), ONERA, 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), GBR, Unité de Catalyse et Chimie du Solide - Equipes du Site Artois (UCCS Artois), Unité de Catalyse et Chimie du Solide - UMR 8181 (UCCS), and Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Ecole Centrale de Lille-Université d'Artois (UA)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Ecole Centrale de Lille-Université d'Artois (UA)
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Brightness ,010504 meteorology & atmospheric sciences ,[SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO] ,media_common.quotation_subject ,Population ,Phase (waves) ,FOS: Physical sciences ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,01 natural sciences ,Asymmetry ,Planet ,0103 physical sciences ,Astrophysics::Solar and Stellar Astrophysics ,education ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,0105 earth and related environmental sciences ,media_common ,Earth and Planetary Astrophysics (astro-ph.EP) ,Physics ,Debris disk ,education.field_of_study ,Spiral galaxy ,Astronomy and Astrophysics ,13. Climate action ,Space and Planetary Science ,Astrophysics::Earth and Planetary Astrophysics ,Jupiter mass ,Astrophysics - Earth and Planetary Astrophysics - Abstract
Transition disks correspond to a short stage between the young protoplanetary phase and older debris phase. Along this evolutionary sequence, the gas component disappears leaving room for a dust-dominated environment where already-formed planets signpost their gravitational perturbations. We endeavor to study the very inner region of the well-known and complex debris, but still gas-rich disk, around HD 141569A using the exquisite high-contrast capability of SPHERE at the VLT. Recent near-infrared (IR) images suggest a relatively depleted cavity within ~200 au, while former mid-IR data indicate the presence of dust at separations shorter than ~100 au. We obtained multi-wavelength images in the near-IR in J, H2, H3 and Ks bands with the IRDIS camera and a 0.95-1.35 micrometers spectral data cube with the IFS. Data were acquired in pupil-tracking mode, thus allowing for angular differential imaging. We discovered several new structures inside 1", of which the most prominent is a bright ring with sharp edges (semi-major axis: 0.4") featuring a strong north-south brightness asymmetry. Other faint structures are also detected from 0.4" to 1" in the form of concentric ringlets and at least one spiral arm. Finally, the VISIR data at 8.6 micrometers suggests the presence of an additional dust population closer in. Besides, we do not detect companions more massive than 1-3 mass of Jupiter. The performance of SPHERE allows us to resolve the extended dust component, which was previously detected at thermal and visible wavelengths, into very complex patterns with strong asymmetries ; the nature of these asymmetries remains to be understood. Scenarios involving shepherding by planets or dust-gas interactions will have to be tested against these observations., Accepted by A&A. 10 pages, 8 figures
- Published
- 2016
36. Further Defining Spectral Type 'Y' and Exploring the Low-mass End of the Field Brown Dwarf Mass Function
- Author
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Roger L. Griffith, J. Davy Kirkpatrick, Christopher R. Gelino, C. G. Tinney, Peter R. Eisenhardt, Edward L. Wright, Ian S. McLean, Kenneth A. Marsh, Gregory N. Mace, Amy Mainzer, Michael F. Skrutskie, Stephen G. Parker, Graeme Salter, Michael C. Cushing, and Adam J. Burgasser
- Subjects
Physics ,Brown dwarf ,FOS: Physical sciences ,Astronomy and Astrophysics ,Context (language use) ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Stellar classification ,Table (information) ,Power law ,Stars ,Astrophysics - Solar and Stellar Astrophysics ,Space and Planetary Science ,Astrophysics::Solar and Stellar Astrophysics ,Astrophysics::Earth and Planetary Astrophysics ,Parallax ,Low Mass ,Solar and Stellar Astrophysics (astro-ph.SR) ,Astrophysics::Galaxy Astrophysics - Abstract
We present the discovery of another seven Y dwarfs from the Wide-field Infrared Survey Explorer (WISE). Using these objects, as well as the first six WISE Y dwarf discoveries from Cushing et al., we further explore the transition between spectral types T and Y. We find that the T/Y boundary roughly coincides with the spot where the J-H colors of brown dwarfs, as predicted by models, turn back to the red. Moreover, we use preliminary trigonometric parallax measurements to show that the T/Y boundary may also correspond to the point at which the absolute H (1.6 um) and W2 (4.6 um) magnitudes plummet. We use these discoveries and their preliminary distances to place them in the larger context of the Solar Neighborhood. We present a table that updates the entire stellar and substellar constituency within 8 parsecs of the Sun, and we show that the current census has hydrogen-burning stars outnumbering brown dwarfs by roughly a factor of six. This factor will decrease with time as more brown dwarfs are identified within this volume, but unless there is a vast reservoir of cold brown dwarfs invisible to WISE, the final space density of brown dwarfs is still expected to fall well below that of stars. We also use these new Y dwarf discoveries, along with newly discovered T dwarfs from WISE, to investigate the field substellar mass function. We find that the overall space density of late-T and early-Y dwarfs matches that from simulations describing the mass function as a power law with slope -0.5 < alpha < 0.0; however, a power-law may provide a poor fit to the observed object counts as a function of spectral type because there are tantalizing hints that the number of brown dwarfs continues to rise from late-T to early-Y. More detailed monitoring and characterization of these Y dwarfs, along with dedicated searches aimed at identifying more examples, are certainly required., 91 pages, 15 figures, accepted for publication in The Astrophysical Journal
- Published
- 2012
37. Signals embedded in the radial velocity noise. Periodic variations in the tau Ceti velocities
- Author
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Duncan J. Wright, Jonathan Horner, James S. Jenkins, Graeme Salter, R. Paul Butler, C. G. Tinney, Robert A. Wittenmyer, D. J. Pinfield, Brad D. Carter, Mikko Tuomi, Simon J. O'Toole, John R. Barnes, Steve Vogt, Hugh R. A. Jones, and Jeremy Bailey
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Physics ,Earth and Planetary Astrophysics (astro-ph.EP) ,010504 meteorology & atmospheric sciences ,Statistical noise ,Starspot ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,01 natural sciences ,Asteroseismology ,Exoplanet ,Radial velocity ,Noise ,13. Climate action ,Space and Planetary Science ,Stellar physics ,0103 physical sciences ,Astrophysics::Solar and Stellar Astrophysics ,Astrophysics::Earth and Planetary Astrophysics ,010303 astronomy & astrophysics ,Astrophysics - Earth and Planetary Astrophysics ,0105 earth and related environmental sciences ,Jitter - Abstract
The abilities of radial velocity exoplanet surveys to detect the lowest-mass extra-solar planets are currently limited by a combination of instrument precision, lack of data, and "jitter". Jitter is a general term for any unknown features in the noise, and reflects a lack of detailed knowledge of stellar physics (asteroseismology, starspots, magnetic cycles, granulation, and other stellar surface phenomena), as well as the possible underestimation of instrument noise. We study an extensive set of radial velocities for the star HD 10700 ($\tau$ Ceti) to determine the properties of the jitter arising from stellar surface inhomogeneities, activity, and telescope-instrument systems, and perform a comprehensive search for planetary signals in the radial velocities. We perform Bayesian comparisons of statistical models describing the radial velocity data to quantify the number of significant signals and the magnitude and properties of the excess noise in the data. We reach our goal by adding artificial signals to the "flat" radial velocity data of HD 10700 and by seeing which one of our statistical noise models receives the greatest posterior probabilities while still being able to extract the artificial signals correctly from the data. We utilise various noise components to assess properties of the noise in the data and analyse the HARPS, AAPS, and HIRES data for HD 10700 to quantify these properties and search for previously unknown low-amplitude Keplerian signals. ..., Comment: 21 pages, 18 figures, accepted for publication in the Astronomy and Astrophysics
- Published
- 2012
- Full Text
- View/download PDF
38. WISE J163940.83-684738.6: A Y Dwarf identified by Methane Imaging
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Graeme Salter, Michael C. Cushing, Edward L. Wright, C. G. Tinney, Christopher R. Gelino, Jacqueline K. Faherty, J. Davy Kirkpatrick, and Roger L. Griffith
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Physics ,Proper motion ,Photometric system ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Astrometry ,Methane ,law.invention ,Telescope ,Photometry (optics) ,chemistry.chemical_compound ,Astrophysics - Solar and Stellar Astrophysics ,chemistry ,Space and Planetary Science ,law ,Spectroscopy ,Spectrograph ,Solar and Stellar Astrophysics (astro-ph.SR) - Abstract
We have used methane imaging techniques to identify the near-infrared counterpart of the bright WISE source WISEJ163940.83-684738.6. The large proper motion of this source (around 3.0arcsec/yr) has moved it, since its original WISE identification, very close to a much brighter background star -- it currently lies within 1.5" of the J=14.90+-0.04 star 2MASS16394085-6847446. Observations in good seeing conditions using methane sensitive filters in the near-infrared J-band with the FourStar instrument on the Magellan 6.5m Baade telescope, however, have enabled us to detect a near-infrared counterpart. We have defined a photometric system for use with the FourStar J2 and J3 filters, and this photometry indicates strong methane absorption, which unequivocally identifies it as the source of the WISE flux. Using these imaging observations we were then able to steer this object down the slit of the FIRE spectrograph on a night of 0.6" seeing, and so obtain near-infrared spectroscopy confirming a Y0-Y0.5 spectral type. This is in line with the object's near-infrared-to-WISE J3--W2 colour. Preliminary astrometry using both WISE and FourStar data indicates a distance of 5.0+-0.5pc and a substantial tangential velocity of 73+-8km/s. WISEJ163940.83-684738.6 is the brightest confirmed Y dwarf in the WISE W2 passband and its distance measurement places it amongst the lowest luminosity sources detected to date., Comment: Accepted for publication in The Astrophysical Journal, 20 September 2012
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- 2012
- Full Text
- View/download PDF
39. Encouraging Participation in Voluntary, Online Staff Development
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Graeme Salter
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Turnover ,business.industry ,Professional development ,Business ,Web engineering ,Public relations ,Marketing - Abstract
In order to determine what factors might lead to increased participation and effectiveness in voluntary online staff development, a case study was conducted. The results revealed a problem known as “churn.” That is, the majority of users went to the site only once or twice and then only for a short amount of time. The major barrier cited by staff was lack of time. This article examines approaches to overcomes involved for both users and developers of online learning activities.
- Published
- 2005
40. Factors Affecting the Adoption of Educational Technology
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Graeme Salter
- Subjects
Technological determinism ,Early adopter ,Engineering ,Knowledge management ,business.industry ,Educational technology ,business - Abstract
There are many in education who appear to think that it is sufficient to purchase and install technology for it to be successfully used (Boddy, 1997). Another common belief is that teachers will “automatically seek to learn about new technology and instructional methods” (Dooley, 1999, p. 38). However, while the investment in technology is there, surveys have consistently found that very few teachers integrate technology into either the K-12 (Newhouse, 1999) or the university classroom (Spotts, 1999). One research study found that even when the technology is readily available and staff accept the functionality of it, they “might not anticipate their personal use of it” (Mitra, Hazen, LaFrance, & Rogan, 1999).
- Published
- 2005
41. E-Learning and M-Learning Problems
- Author
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Graeme Salter
- Subjects
Multimedia ,Computer science ,M-learning ,E-learning (theory) ,Educational technology ,computer.software_genre ,computer - Abstract
The use of online teaching in education is expanding at a rapid rate. Some may be tempted to view technology as an educational panacea (Herrington & Herrington, 1998). However, the existence of any technology does not guarantee that good educational material will be provided or that effective learning will happen (Boddy, 1997). Online teaching has the “potential to be just as inflexible and inappropriate as any other form of poor instruction” (Bennett, Priest & Macpherson, 1999, p. 208). Problems associated with online learning are often overlooked or not fully investigated (Hara & Kling, 1999). It is important not to be blinded by technology. We need to recognize and study these problems to obtain a broader picture of the impact of technology in teaching. This author is an early and enthusiastic adopter of technology in teaching. However, he has learned through experience and research that it is important to identify problems, both real and perceived, in order to develop strategies to overcome them. For example, innovators are prepared to be relatively understanding of technical problems, but the bulk of users are not likely to be as forgiving (Freeman, 1997).
- Published
- 2005
42. Direct Imaging Of Long Period Radial Velocity Targets With NICI
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Graeme Salter, Hugh R. A. Jones, James S. Jenkins, Simon J. O'Toole, Robert A. Wittenmyer, and C. G. Tinney
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Physics ,Near-infrared spectroscopy ,Brown dwarf ,Astronomy ,Minimum mass ,Astronomy and Astrophysics ,Astrophysics ,Planetary system ,Radial velocity ,Space and Planetary Science ,Planet ,Astrophysics::Solar and Stellar Astrophysics ,Orbiting body ,Astrophysics::Earth and Planetary Astrophysics ,Low Mass - Abstract
We are finally entering an era where radial velocity and direct imaging parameter spaces are starting to overlap. Radial velocity measurements provide us with a minimum mass for an orbiting companion (the mass as a function of the inclination of the system). By following up these long period radial velocity detections with direct imaging we can determine whether a trend seen is due to an orbiting planet at low inclination or an orbiting brown dwarf at high inclination. In the event of a non-detection we are still able to put a limit on the maximum mass of the orbiting body. The Anglo-Australian Planet Search is one of the longest baseline radial velocity planet searches in existence, amongst its targets are many that show long period trends in the data. Here we present our direct imaging survey of these objects with our results to date. ADI Observations have been made using NICI (Near Infrared Coronagraphic Imager) on Gemini South and analysed using an in house, LOCI-like, post processing. Copyright © 2013, International Astronomical Union.
- Published
- 2013
43. THE ANGLO-AUSTRALIAN PLANET SEARCH. XXII. TWO NEW MULTI-PLANET SYSTEMS
- Author
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Jonathan Horner, Brad D. Carter, Mikko Tuomi, Robert A. Wittenmyer, Graeme Salter, James S. Jenkins, C. G. Tinney, Simon J. O'Toole, R. P. Butler, Steven S. Vogt, Zhenyu Zhang, Eugenio J. Rivera, Jeremy Bailey, and Hugh R. A. Jones
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Earth and Planetary Astrophysics (astro-ph.EP) ,Physics ,media_common.quotation_subject ,FOS: Physical sciences ,Astronomy ,Minimum mass ,Astronomy and Astrophysics ,Jupiter ,Orbit ,Stars ,Space and Planetary Science ,Planet ,Long period ,Astrophysics::Earth and Planetary Astrophysics ,Eccentricity (behavior) ,Astrophysics - Earth and Planetary Astrophysics ,media_common - Abstract
We report the detection of two new planets from the Anglo-Australian Planet Search. These planets orbit two stars each previously known to host one planet. The new planet orbiting HD 142 has a period of 6005\pm427 days, and a minimum mass of 5.3M_Jup. HD142c is thus a new Jupiter analog: a gas-giant planet with a long period and low eccentricity (e = 0.21 \pm 0.07). The second planet in the HD 159868 system has a period of 352.3\pm1.3 days, and m sin i=0.73\pm0.05 M_Jup. In both of these systems, including the additional planets in the fitting process significantly reduced the eccentricity of the original planet. These systems are thus examples of how multiple-planet systems can masquerade as moderately eccentric single-planet systems., 31 pages, 8 figures, accepted for publication in ApJ
- Published
- 2012
44. Automatic changes in a serial learning task
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Graeme Salter and RobertJ. Barry
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Serial learning ,Neuropsychology and Physiological Psychology ,Computer science ,Physiology (medical) ,General Neuroscience ,Speech recognition ,Task (project management) - Published
- 1991
45. Dynamical models to explain observations with SPHERE in planetary systems with double debris belts
- Author
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N. Pawellek, R. Ligi, Raphaël Galicher, C. Lazzoni, Luigi Lessio, T. Kopytova, Michael Meyer, Francois Wildi, M. Feldt, Anne-Marie Lagrange, Daniela Fantinel, Ch. Ginski, Anthony Cheetham, Bernardo Salasnich, T. Schmidt, Maud Langlois, V. De Caprio, Wolfgang Brandner, S. Incorvaia, Graeme Salter, G. Farisato, Mickael Bonnefoy, M. Cudel, Salvo Scuderi, Francesco Marzari, Alice Zurlo, J. L. Beuzit, E. Sissa, Markus Janson, Pietro Bruno, Andreas Bazzon, Philippe Delorme, Dino Mesa, Anne-Lise Maire, M. Samland, C. Perrot, Stéphane Udry, R. G. Gratton, F. Cantalloube, Riccardo Claudi, Daniel Rouan, Sebastian Daemgen, Henning Avenhaus, Beth Biller, Jacopo Antichi, S. Peretti, Enrico Cascone, E. Sezestre, Johan Olofsson, Th. Henning, H. LeCoroller, J. Milli, Enrico Giro, Jean-Loup Baudino, Massimo Turatto, Andrea Baruffolo, Julien Girard, M. Kasper, Esther Buenzli, Janis Hagelberg, Gael Chauvin, Quentin Kral, David Mouillet, Arthur Vigan, Mariangela Bonavita, Francois Menard, Anthony Boccaletti, Silvano Desidera, INAF - Osservatorio Astronomico di Padova (OAPD), Istituto Nazionale di Astrofisica (INAF), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-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), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), INAF - Osservatorio Astrofisico di Arcetri (OAA), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, INAF - Osservatorio Astronomico di Capodimonte (OAC), Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève (UNIGE), Institute of Astronomy [ETH Zürich], Department of Physics [ETH Zürich] (D-PHYS), 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), Leiden Observatory [Leiden], Universiteit Leiden [Leiden], Stockholm University, European Southern Observatory (ESO), Geneva Observatory, University of Geneva [Switzerland], 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), 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 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]), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)- Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Université de Genève = University of Geneva (UNIGE), Universiteit Leiden, ANR-16-CE31-0013,PLANET-FORMING-DISKS,De meilleurs modèles pour de meilleures données(2016), Pawellek, Nicole [0000-0002-9385-9820], and Apollo - University of Cambridge Repository
- Subjects
GENERAL [KUIPER BELT] ,IMAGE PROCESSING ,GENERALS [KUIPER BELT] ,FOS: Physical sciences ,DEBRIS ,Orbital eccentricity ,techniques: image processing ,Astrophysics ,IMAGE PROCESSING [TECHNIQUES] ,01 natural sciences ,methods: analytical ,Planet ,instrumentation: high angular resolution ,0103 physical sciences ,ANALYTICAL [METHODS] ,Circular orbit ,010303 astronomy & astrophysics ,Physics ,Earth and Planetary Astrophysics (astro-ph.EP) ,PLANET-DISK INTERACTIONS ,Debris disk ,planet-disk interactions ,010308 nuclear & particles physics ,Astronomy and Astrophysics ,Mass ratio ,Planetary system ,Exoplanet ,SPHERES ,13. Climate action ,Space and Planetary Science ,OBSERVATIONAL [METHODS] ,HIGH ANGULAR RESOLUTION [INSTRUMENTATION] ,Kuiper belt: general ,Astrophysics::Earth and Planetary Astrophysics ,ORBITS ,methods: observational ,Low Mass ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,Astrophysics - Earth and Planetary Astrophysics ,PLANETS - Abstract
A large number of systems harboring a debris disk show evidence for a double belt architecture. One hypothesis for explaining the gap between the belts is the presence of one or more planets dynamically carving it. This work aims to investigate this scenario in systems harboring two components debris disks. All the targets in the sample were observed with the SPHERE instrument which performs high-contrast direct imaging. Positions of the inner and outer belts were estimated by SED fitting of the infrared excesses or, when available, from resolved images of the disk. Very few planets have been observed so far in debris disks gaps and we intended to test if such non-detections depend on the observational limits of the present instruments. This aim is achieved by deriving theoretical predictions of masses, eccentricities and semi-major axes of planets able to open the observed gaps and comparing such parameters with detection limits obtained with SPHERE. The relation between the gap and the planet is due to the chaotic zone around the orbit of the planet. The radial extent of this zone depends on the mass ratio between the planet and the star, on the semi-major axis and on the eccentricity of the planet and it can be estimated analytically. We apply the formalism to the case of one planet on a circular or eccentric orbit. We then consider multi-planetary systems: 2 and 3 equal-mass planets on circular orbits and 2 equal-mass planets on eccentric orbits in a packed configuration. We then compare each couple of values (M,a), derived from the dynamical analysis of single and multiple planetary models, with the detection limits obtained with SPHERE. Our results show that the apparent lack of planets in gaps between double belts could be explained by the presence of a system of two or more planets possibly of low mass and on an eccentric orbits whose sizes are below the present detection limits., Comment: 23 pages, 13 figures
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