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5 results on '"Zins, Gerard"'

1. The beta Pictoris system: Setting constraints on the planet and the disk structures at mid-IR wavelengths with NEAR

Author

Skaf, Nour, Boccaletti, Anthony, Pantin, Eric, Thebault, Philippe, Kral, Quentin, Danielski, Camilla, Galicher, Raphael, Milli, Julien, Lagrange, Anne-Marie, Baruteau, Clement, Kenworthy, Matthew, Absil, Olivier, Langlois, Maud, Olofsson, Johan, Chauvin, Gael, Huelamo, Nuria, Delorme, Philippe, Charnay, Benjamin, Guyon, Olivier, Bonnefoy, Michael, Cantalloube, Faustine, Hoeijmakers, H. Jens, Käufl, Ulli, Kasper, Markus, Maire, Anne-Lise, Mâlin, Mathilde, Siebenmorgen, Ralf, Snellen, Ignas, and Zins, Gerard

Subjects
Earth and Planetary Astrophysics (astro-ph.EP), FOS: Physical sciences, Astrophysics - Earth and Planetary Astrophysics
Abstract

[abridged] We analyzed mid-infrared high-contrast coronagraphic images of the beta Pictoris system, taking advantage of the NEAR experiment using the VLT/VISIR instrument. The goal of our analysis is to investigate both the detection of the planet beta Pictoris b and of the disk features at mid-IR wavelengths. In addition, by combining several epochs of observation, we expect to constrain the position of the known clumps and improve our knowledge on the dynamics of the disk. To evaluate the planet b flux contribution, we extracted the photometry and compared it to the flux published in the literature. In addition, we used previous data from T-ReCS and VISIR, to study the evolution of the position of the southwest clump that was initially observed in the planetary disk back in 2003. While we did not detect the planet b, we were able to put constraints on the presence of circumplanetary material, ruling out the equivalent of a Saturn-like planetary ring around the planet. The disk presents several noticeable structures, including the known southwest clump. Using a 16-year baseline, sampled with five epochs of observations, we were able to examine the evolution of the clump: the clump orbits in a Keplerian motion with an sma of 56.1+-0.4 au. In addition to the known clump, the images clearly show the presence of a second clump on the northeast side of the disk and fainter and closer structures that are yet to be confirmed. We found correlations between the CO clumps detected with ALMA and the mid-IR images. If the circumplanetary material were located at the Roche radius, the maximum amount of dust determined from the flux upper limit around beta Pictoris b would correspond to the mass of an asteroid of 5 km in diameter. Finally, the Keplerian motion of the southwestern clump is possibly indicative of a yet-to-be-detected planet or signals the presence of a vortex., Comment: Accepted in Astronomy and Astrophysics

Published
2023
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2. NaCo — The Story of a Lifetime

Author

Schmidtobreick, Linda, Ageorges, Nancy, Amico, Paola, Brandner, Wolfgang, Cerda, Suzana, Cid, Claudia, Close, Laird, Garces, Eduardo, Gillet, Gordon, Girard, Julien H., Guajardo, Patricia, Hau, George, Hummel, Wolfgang, Jung, Yves, Kasper, Markus, Lidman, Christopher, Lundin, Lars Kristian, Mardones, Pedro, Mawet, Dimitri, O’Neal, Jared, Pompei, Emanuela, Schmutzer, Ricardo, Silva, Karleyne, Smoker, Jonathan, Soenke, Christian, Tacconi-Garman, Lowell E., Valenti, Elena, Valenzuela, Javier, Velasquez, Jose, and Zins, Gerard

Abstract

NaCo was switched off on 2 October 2019, almost 18 years after its first light. The last exposure was of the standard star HD590 as part of the close-out calibrations. To date, 699 papers have been published using NaCo data, including observations of the Galactic centre, direct images of exoplanets orbiting their stars, young stellar objects, brown dwarfs, massive stars, stellar clusters, Solar System objects, SN 1987A and several extragalactic sources. We present a short history of the life and achievements of NaCo from the viewpoint of the Instrument Operation Team, Instrument Scientists, and Instrument Engineers., Published in The Messenger vol. 179, pp. 7-11, March 2020.

Published
2020
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3. NEAR: First Results from the Search for Low-Mass Planets in α Cen

Author

Kasper, Markus, Arsenault, Robin, Käufl, Ulli, Jakob, Gerd, Leveratto, Serban, Zins, Gerard, Pantin, Eric, Duhoux, Philippe, Riquelme, Miguel, Kirchbauer, Jean-Paul, Kolb, Johann, Pathak, Prashant, Siebenmorgen, Ralf, Soenke, Christian, Fuenteseca, Eloy, Sterzik, Michael, Ageorges, Nancy, Gutruf, Sven, Kampf, Dirk, Reutlinger, Arnd, Absil, Olivier, Delacroix, Christian, Maire, Anne-Lise, Huby, Elsa, Guyon, Olivier, Klupar, Pete, Mawet, Dimitri, Ruane, Garreth, Karlsson, Mikael, Dohlen, Kjetil, Vigan, Arthur, N’Diaye, Mamadou, Quanz, Sascha, Carlotti, Alexis, Joseph Louis LAGRANGE (LAGRANGE), 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, and COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS]Physics [physics], 0303 health sciences, 03 medical and health sciences, [SDU]Sciences of the Universe [physics], 0103 physical sciences, Astrophysics::Instrumentation and Methods for Astrophysics, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics::Earth and Planetary Astrophysics, 010303 astronomy & astrophysics, 01 natural sciences, Astrophysics::Galaxy Astrophysics, 030304 developmental biology
Abstract

ESO, in collaboration with the Breakthrough Initiatives, has modified the VLT mid-infrared imager VISIR to greatly enhance its ability as a planet finder. It has conducted a 100-hour observing campaign to search for low-mass planets around both components of the binary a Centauri, part of the closest stellar system to the Earth. Using adaptive optics and high-performance coronagraphy, the instrument reached unprecedented contrast and sensitivity allowing it to see Neptune-sized planets in the habitable zone, if present. The experiment allowed us to characterise the current limitations of the instrument. We conclude that the detection of rocky planets similar to Earth in the habitable zone of the a Centauri System is already possible with 8-metre-class telescopes in the thermal infrared., Published in The Messenger vol. 178, pp. 5-9, December 2019.

Published
2019
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4. NEAR: Low-mass Planets in α Cen with VISIR

Author

Kasper, Markus, Arsenault, Robin, Käufl, Hans-Ulrich, Jakob, Gerd, Fuenteseca, Eloy, Riquelme, Miguel, Siebenmorgen, Ralf, Sterzik, Michael, Zins, Gerard, Ageorges, Nancy, Gutruf, Sven, Reutlinger, Arnd, Kampf, Dirk, Absil, Olivier, Carlomagno, Brunella, Guyon, Olivier, Klupar, Pete, Mawet, Dimitri, Ruane, Garreth, Karlsson, Mikael, Pantin, Eric, and Dohlen, Kjetil

Subjects
0301 basic medicine, 03 medical and health sciences, 030104 developmental biology, 0103 physical sciences, Astrophysics::Instrumentation and Methods for Astrophysics, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics::Earth and Planetary Astrophysics, 7. Clean energy, 010303 astronomy & astrophysics, 01 natural sciences, Astrophysics::Galaxy Astrophysics
Abstract

ESO, in collaboration with the Breakthrough Initiatives, is working to modify the Very Large Telescope mid-IR imager (VISIR) to greatly enhance its ability to search for potentially habitable planets around both components of the binary Alpha Centauri, part of the closest stellar system to the Earth. Much of the funding for the NEAR (New Earths in the Alpha Cen Region) project is provided by the Breakthrough Initiatives, and ESO mostly provides staff and observing time. The concept combines adaptive optics using the deformable secondary mirror at Unit Telescope 4, a new annular groove phase mask (AGPM) coronagraph optimised for the most sensitive spectral bandpass in the N-band, and a novel internal chopper system for noise filtering based on a concept for longer wavelengths invented by the microwave pioneer Robert Dicke. The NEAR experiment is relevant to the mid-infrared METIS instrument on the Extremely Large Telescope, as the knowledge gained and proof of concept will be transferable., Published in The Messenger vol. 169, pp. 16-20, September 2017.

Published
2017
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5. SPHERE on-sky performance compared with budget predictions

Author

Dohlen, Kjetil, Vigan, Arthur, Mouillet, David, Wildi, François, Sauvage, Jean-François, Fusco, Thierry, Beuzit, Jean-Luc, Puget, Pascal, Le Mignant, David, Roelfsema, Ronald, Pragt, Johan, Schmid, Hans Martin, Gratton, Raffaele, Mesa, Dino, Claudi, Riccardo, Langlois, Maud, Costille, Anne, Hugot, Emmanuel, O'Neil, Jared, Guerra, Juan Carlos, N'Diaye, Mamadou, Girard, Julien, Mawet, Dimitri, Zins, Gerard, Evans, Christopher, Simard, Luc, Takami, Hideki, Sauvage, François, Beuzit, Luc, 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), 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]), Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève = University of Geneva (UNIGE), DOTA, ONERA, Université Paris Saclay (COmUE) [Châtillon], ONERA-Université Paris Saclay (COmUE), NOVA-ASTRON, Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Space Telescope Science Institute (STSci), European Southern Observatory (ESO), California Institute of Technology (CALTECH), European Southern Observatory [Santiago] (ESO), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire Avancé de Spectroscopie pour les Intéractions la Réactivité et l'Environnement - UMR 8516 (LASIRE), Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Département de Radiologie [CHU de Rennes], Université de Rennes (UR), 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 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 de Genève (UNIGE), DOTA, ONERA, Université Paris Saclay [Châtillon], ONERA-Université Paris-Saclay, 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), Laboratoire de Spectrochimie Infrarouge et Raman - UMR 8516 (LASIR), Centre National de la Recherche Scientifique (CNRS)-Université de Lille, Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES), Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Centrale Lille Institut (CLIL), Evans, Christopher J., Simard, Luc, and Takami, Hideki

Subjects
Infrared, Computer science, Zernike polynomials, Polarimetry, FOS: Physical sciences, 01 natural sciences, Deformable mirror, law.invention, 010309 optics, symbols.namesake, Optics, Integral field spectrograph, law, Observatory, 0103 physical sciences, Instrumentation and Methods for Astrophysics (astro-ph.IM), 010303 astronomy & astrophysics, Coronagraph, Wavefront, business.industry, Near-infrared spectroscopy, Astrophysics::Instrumentation and Methods for Astrophysics, First light, symbols, Astrophysics - Instrumentation and Methods for Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], business
Abstract

The SPHERE (spectro-photometric exoplanet research) extreme-AO planet hunter saw first light at the VLT observatory on Mount Paranal in May 2014 after ten years of development. Great efforts were put into modelling its performance, particularly in terms of achievable contrast, and to budgeting instrumental features such as wave front errors and optical transmission to each of the instrument's three focal planes, the near infrared dual imaging camera IRDIS, the near infrared integral field spectrograph IFS and the visible polarimetric camera ZIMPOL. In this paper we aim at comparing predicted performance with measured performance. In addition to comparing on-sky contrast curves and calibrated transmission measurements, we also compare the PSD-based wave front error budget with in-situ wave front maps obtained thanks to a Zernike phase mask, ZELDA, implemented in the infrared coronagraph wheel. One of the most critical elements of the SPHERE system is its high-order deformable mirror, a prototype 40x40 actuator piezo stack design developed in parallel with the instrument itself. The development was a success, as witnessed by the instrument performance, in spite of some bad surprises discovered on the way. The devastating effects of operating without taking properly into account the loss of several actuators and the thermally and temporally induced variations in the DM shape will be analysed, and the actions taken to mitigate these defects through the introduction of specially designed Lyot stops and activation of one of the mirrors in the optical train will be described., 11 pages, 16 figures. Presented at the SPIE astronomy conference in Edinburgh 2016

Published
2016
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