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2. A family portrait of disk inner rims around Herbig Ae/Be stars

Author

J. Kluska, J.-P. Berger, F. Malbet, B. Lazareff, M. Benisty, J.-B. Le Bouquin, O. Absil, F. Baron, A. Delboulbé, G. Duvert, A. Isella, L. Jocou, A. Juhasz, S. Kraus, R. Lachaume, F. Ménard, R. Millan-Gabet, J. D. Monnier, T. Moulin, K. Perraut, S. Rochat, C. Pinte, F. Soulez, M. Tallon, W.-F. Thi, E. Thiébaut, W. Traub, G. Zins

Published
2020
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3. Disk and wind interaction in the young stellar object MWC 297 spatially resolved with AMBER/VLTI

Author

F. Malbet, M. Benisty, W.-J. de Wit, S. Kraus, A. Meilland, F. Millour, E. Tatulli, J.-P. Berger, O. Chesneau, K.-H. Hofmann, A. Isella, A. Natta, R. G. Petrov, T. Preibisch, P. Stee, L. Testi, G. Weigelt, P. Antonelli, U. Beckmann, Y. Bresson, A. Chelli, M. Dugué, G. Duvert, S. Gennari, L. Glück, P. Kern, S. Lagarde, E. Le Coarer, F. Lisi, K. Perraut, P. Puget, F. Rantakyrö, S. Robbe-Dubois, A. Roussel, G. Zins, M. Accardo, B. Acke, K. Agabi, E. Altariba, B. Arezki, E. Aristidi, C. Baffa, J. Behrend, T. Blöcker, S. Bonhomme, S. Busoni, F. Cassaing, J.-M. Clausse, J. Colin, C. Connot, A. Delboulbé, A. Domiciano de Souza, T. Driebe, P. Feautrier, D. Ferruzzi, T. Forveille, E. Fossat, R. Foy, D. Fraix-Burnet, A. Gallardo, E. Giani, C. Gil, A. Glentzlin, M. Heiden, M. Heininger, O. Hernandez Utrera, D. Kamm, M. Kiekebusch, D. Le Contel, J.-M. Le Contel, T. Lesourd, B. Lopez, M. Lopez, Y. Magnard, A. Marconi, G. Mars, G. Martinot-Lagarde, P. Mathias, P. Mège, J.-L. Monin, D. Mouillet, D. Mourard, E. Nussbaum, K. Ohnaka, J. Pacheco, C. Perrier, Y. Rabbia, S. Rebattu, F. Reynaud, A. Richichi, A. Robini, M. Sacchettini, D. Schertl, M. Schöller, W. Solscheid, A. Spang, P. Stefanini, M. Tallon, I. Tallon-Bosc, D. Tasso, F. Vakili, O. von der Lühe, J.-C. Valtier, M. Vannier, and N. Ventura

Subjects
Physics, 010308 nuclear & particles physics, Astrophysics::High Energy Astrophysical Phenomena, Young stellar object, Continuum (design consultancy), Visibility (geometry), Equator, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, 01 natural sciences, Spectral line, Wavelength, Space and Planetary Science, 0103 physical sciences, Thick disk, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Line (formation)
Abstract

The young stellar object MWC 297 has been observed with the VLT interferometer equipped with the AMBER instrument. MWC 297 has been spatially resolved in the continuum with a visibility of 0.50 as well as in the Br gamma emission line where the visibility decrease to a lower value of 0.33. This change in the visibility with the wavelength can be interpreted by the presence of an optically thick disk responsible for the visibility in the continuum and of a stellar wind traced by Br gamma and whose apparent size is 40% larger. We validate this interpretation by building a model of the stellar environment that combines a geometrically thin, optically thick accretion disk model consisting of gas and dust, and a latitude-dependent stellar wind outflowing above the disk surface. The continuum emission and visibilities obtained from this model are fully consistent with the interferometric AMBER data. They agree also with existing optical, near-infrared spectra and other broad-band near-infrared interferometric visibilities. A picture emerges in which MWC 297 is surrounded by an equatorial flat disk that is possibly still accreting and an outflowing wind which has a much higher velocity in the polar region than at the equator. [abridged]

Published
2007
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4. An asymmetry detected in the disk of κ Canis Majoris with AMBER/VLTI

Author

A. Meilland, F. Millour, P. Stee, A. Domiciano de Souza, R. G. Petrov, D. Mourard, S. Jankov, S. Robbe-Dubois, A. Spang, E. Aristidi, P. Antonelli, U. Beckmann, Y. Bresson, A. Chelli, M. Dugué, G. Duvert, S. Gennari, L. Glück, P. Kern, S. Lagarde, E. Le Coarer, F. Lisi, F. Malbet, K. Perraut, P. Puget, F. Rantakyrö, A. Roussel, E. Tatulli, G. Weigelt, G. Zins, M. Accardo, B. Acke, K. Agabi, E. Altariba, B. Arezki, C. Baffa, J. Behrend, T. Blöcker, S. Bonhomme, S. Busoni, F. Cassaing, J.-M. Clausse, J. Colin, C. Connot, A. Delboulbé, T. Driebe, P. Feautrier, D. Ferruzzi, T. Forveille, E. Fossat, R. Foy, D. Fraix-Burnet, A. Gallardo, E. Giani, C. Gil, A. Glentzlin, M. Heiden, M. Heininger, O. Hernandez Utrera, K.-H. Hofmann, D. Kamm, M. Kiekebusch, S. Kraus, D. Le Contel, J.-M. Le Contel, T. Lesourd, B. Lopez, M. Lopez, Y. Magnard, A. Marconi, G. Mars, G. Martinot-Lagarde, P. Mathias, P. Mège, J.-L. Monin, D. Mouillet, E. Nussbaum, K. Ohnaka, J. Pacheco, C. Perrier, Y. Rabbia, S. Rebattu, F. Reynaud, A. Richichi, A. Robini, M. Sacchettini, D. Schertl, M. Schöller, W. Solscheid, P. Stefanini, M. Tallon, I. Tallon-Bosc, D. Tasso, L. Testi, F. Vakili, O. von der Lühe, J.-C. Valtier, M. Vannier, and N. Ventura

Subjects
Physics, 010308 nuclear & particles physics, Be star, media_common.quotation_subject, Continuum (design consultancy), Astronomy and Astrophysics, Astrophysics, 01 natural sciences, Asymmetry, Stars, Polar wind, Space and Planetary Science, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Spectral energy distribution, Astrophysics::Earth and Planetary Astrophysics, Spectral resolution, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, media_common, Line (formation)
Abstract

Aims. We study the geometry and kinematics of the circumstellar environment of the Be star Kappa CMa in the Br gamma emission line and its nearby continuum. Methods. We use the VLTI/AMBER instrument operating in the K band which provides a spatial resolution of about 6 mas with a spectral resolution of 1500 to study the kinematics within the disk and to infer its rotation law. In order to obtain more kinematical constraints we also use an high spectral resolution Pa beta line profile obtain in December 2005 at the Observatorio do Pico do Dios, Brazil and we compile V/R line profile variations and spectral energy distribution data points from the literature. Results. Using differential visibilities and differential phases across the Br gamma line we detect an asymmetry in the disk. Moreover, we found that kappa CMa seems difficult to fit within the classical scenario for Be stars, illustrated recently by alpha Arae observations, i.e. a fast rotating B star close to its breakup velocity surrounded by a Keplerian circumstellar disk with an enhanced polar wind. Finally we discuss the possibility for kappa CMa to be a critical rotator with a Keplerian rotating disk and try to see if the detected asymmetry can be interpreted within the "one-armed" viscous disk framework.

Published
2006
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5. Chalcogenide glass planar MIR couplers for future chip based Bracewell interferometers

Author

F Malbet, M J Creech-Eakman, P G Tuthill, Kenchington Goldsmith, Harry-Dean, Cvetojevic, N., Ma, Pan, Tuthill, Peter G., Eggleton, Benjamin J., Lawrence, J. S., Debbarma, Sukhanta, Luther-Davies, Barry, Madden, Steve, Ireland, Michael, F Malbet, M J Creech-Eakman, P G Tuthill, Kenchington Goldsmith, Harry-Dean, Cvetojevic, N., Ma, Pan, Tuthill, Peter G., Eggleton, Benjamin J., Lawrence, J. S., Debbarma, Sukhanta, Luther-Davies, Barry, Madden, Steve, and Ireland, Michael

Abstract

Photonic integrated circuits are established as the technique of choice for a number of astronomical processing functions due to their compactness, high level of integration, low losses, and stability. Temperature control, mechanical vibration and acoustic noise become controllable for such a device enabling much more complex processing than can realistically be considered with bulk optics. To date the benefits have mainly been at wavelengths around 1550 nm but in the important Mid-Infrared region, standard photonic chips absorb light strongly. Chalcogenide glasses are well known for their transparency to beyond 10000 nm, and the first results from coupler devices intended for use in an interferometric nuller for exoplanetary observation in the Mid-Infrared L' band (3800-4200 nm) are presented here showing that suitable performance can be obtained both theoretically and experimentally for the first fabricated devices operating at 4000 nm.

Published
2016

6. FU Orionis Resolved by Infrared Long-Baseline Interferometry at a 2 AU Scale

Author

F. Malbet, J.-P. Berger, M. M. Colavita, C. D. Koresko, C. Beichman, A. F. Boden, S. R. Kulkarni, B. F. Lane, D. W. Mobley, X. P. Pan, M. Shao, G. T. Van Belle, and J. K. Wallace

Subjects
Physics, Photosphere, Infrared, Scattering, Young stellar object, Astrophysics (astro-ph), Resolution (electron density), FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Lambda, Interferometry, Palomar Testbed Interferometer, Space and Planetary Science
Abstract

We present the first infrared interferometric observations of a young stellar object with a spatial projected resolution better than 2 AU. The observations were obtained with the Palomar Testbed Interferometer. FU Ori exhibits a visibility of V^2 =0.72 +/- 0.07 for a 103 +/- 5 m projected baseline at lambda = 2.2 microns. The data are consistent on the spatial scale probed by PTI both with a binary system scenario (maximum magnitude difference of 2.7 +/- 0.5 mag and smallest separation of 0.35 +/- 0.05 AU) and a standard luminous accretion disk model (approx. accretion rate of 6e-5 Mo/yr) where the thermal emission dominates the stellar scattering, and inconsistent with a single stellar photosphere., 13 pages, 4 figures, accepted for publication in ApJL

Published
1998
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7. Very Close Environments of Young Stars

Author

F. Malbet

Subjects
Physics, Infrared, Astrophysics::High Energy Astrophysical Phenomena, Gamma ray, Magnetosphere, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Protoplanetary disk, Accretion (astrophysics), Wavelength, Stars, Planet, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract

Long-baseline interferometry at infrared wavelengths allows the innermost regions around young stars to be observed. These observations directly probe the location of the dust and gas in the disks. The characteristic sizes of these regions found are larger than previously thought. These results have motivated in part a new class of models of the inner disk structure, but the precise understanding of the origin of these low visibilities is still in debate. Mid-infrared observations probe disk emission over a larger range of scales revealing mineralogy gradients in the disk. Spectrally resolved observations allow the dust and gas to be studied separately showing that the Brackett gamma emission can find its origin either in a wind or in a magnetosphere and that there is probably no correlation between the location of the Brackett gamma emission and accretion. In a certain number of cases, the very high spatial resolution reveals very close companions and can determine their masses. Overall, these results provide essential information on the structure and the physical properties of close regions surrounding young stars especially where planet formation is suspected to occur.

Published
2013
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9. High Angular Resolution Observations of Protostellar Disks

Author

J.-L. Monin, J. Bouvier, and F. Malbet

Subjects
Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract

The existence of circumstellar disks around young stellar objects like T Tauri stars is now well accepted. Such disks would have solar system sizes and, at the distance of the nearest star forming cloud, an angular diameter of 0.01 to 1 arcsecond at most, requiring very high angular resolution to be detected. Due to the nature of the emission process in circumstellar disks and to chromatic properties of ground based observations, disk imaging is expected to be more efficient in the near infrared. Also, multi-aperture interferometry in this wavelength range (1 – 10 μm) is expected to bring considerable insight into the disks properties and evolution in revealing their inner physical structure.In this paper, we present synthetic images of circumstellar accretion disks. The images have been computed from a complete disk vertical structure model.

Published
1994
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10. An integrated optics beam combiner for the second generation VLTI instruments

Author

M. Benisty, J.-P. Berger, L. Jocou, P. Labeye, F. Malbet, K. Perraut, P. Kern, Laboratoire d'Astrophysique de Grenoble (LAOG), and Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Computer science, Aperture synthesis, FOS: Physical sciences, 01 natural sciences, law.invention, 010309 optics, Optics, Optical path, law, K band, 0103 physical sciences, Instrumentation and Methods for Astrophysics (astro-ph.IM), 010303 astronomy & astrophysics, Very Large Telescope, business.industry, Near-infrared spectroscopy, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy and Astrophysics, H band, Polarization (waves), Wavelength, Interferometry, Space and Planetary Science, Achromatic lens, business, Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

The very recent years have seen a promising start in scientific publications making use of images produced by near-infrared long-baseline interferometry. The technique has reached, at last, a technical maturity level that opens new avenues for numerous astrophysical topics requiring milli-arcsecond model-independent imaging. The Very Large Telescope Interferometer (VLTI) is on the path to be equipped with instruments capable to combine between four to six telescopes. In the framework of the VLTI second generation instruments Gravity and VSI, we propose a new beam combining concept using Integrated Optics (IO) technologies with a novel ABCD-like fringe encoding scheme. Our goal is to demonstrate that IO-based combination brings considerable advantages in terms of instrumental design and performance. We therefore aim at giving a full characterization of an IO beam combiner to establish its performances and check its compliance with the specifications of an imaging instrument. Laboratory measurements were made in the H band with a dedicated testbed. We studied the beam combiners through the analysis of throughput, instrumental visibilities, phases and closure phases in wide band as well as with spectral dispersion. Study of the polarization properties is also done. We obtain competitive throughput, high and stable instrumental contrasts, stable but non-zero closure phases which we attribute to internal well calibrable optical path differences. We validate a new static and achromatic phase shifting IO function close to the nominal 90deg value. All these observables show limited chromaticity over the H band range. Our results demonstrate that such ABCD-like beam combiners are particularly well suited to achieve aperture synthesis imaging. This opens the way to extend to all near infrared wavelengths and in particular, the K band., 13 pages, 11 figures, 13 tables; Accepted by A&A

Published
2009
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11. Milli-arcsecond Astrophysics with VSI, the VLTI Spectro-imager in the ELT Era

Author

F. Malbet, D. Buscher, G. Weigelt, P. Garcia, M. Gai, D. Lorenzetti, J. Surdej, J. Hron, R. Neuhäuser, P. Kern, L. Jocou, J.-P. Berger, O. Absil, U. Beckmann, L. Corcione, G. Duvert, M. Filho, P. Labeye, E. Le Coarer, G. Li Causi, J. Lima, K. Perraut, E. Tatulli, E. Thiébaut, J. Young, G. Zins, A. Amorim, B. Aringer, T. Beckert, M. Benisty, X. Bonfils, A. Chelli, O. Chesneau, A. Chiavassa, R. Corradi, M. de Becker, A. Delboulbé, G. Duchêne, T. Forveille, C. Haniff, E. Herwats, K.-H. Hofmann, J.-B. Le Bouquin, S. Ligori, D. Loreggia, A. Marconi, A. Moitinho, B. Nisini, P.-O. Petrucci, J. Rebordao, R. Speziali, L. Testi, F. Vitali, 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), Cavendish Laboratory, University of Cambridge [UK] (CAM), Max-Planck-Institut für Radioastronomie (MPIFR), Laboratoire de Modélisation Multi-échelles des Combustibles (LM2C), Service d'Etudes de Simulation du Comportement du combustibles (SESC), Département d'Etudes des Combustibles (DEC), CEA-Direction de l'Energie Nucléaire (CEA-DEN), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-CEA-Direction de l'Energie Nucléaire (CEA-DEN), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Département d'Etudes des Combustibles (DEC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), INAF - Osservatorio Astrofisico di Torino (OATo), Istituto Nazionale di Astrofisica (INAF), Osservatorio di Astrofisica di Roma (OAR), Institut d'Astrophysique et de Géophysique [Liège], Université de Liège, Institut für Astrophysik [Wien], Universität Wien, Astrophysical Institute and University Observatory [Jena] (AIU), Friedrich-Schiller-Universität Jena, Institut d'Electronique du Solide et des Systèmes (InESS), Centre National de la Recherche Scientifique (CNRS), Centre d'Études Préhistoire, Antiquité, Moyen-Age (CEPAM), Université Nice Sophia Antipolis (... - 2019) (UNS), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Centro de Astrofísica da Universidade do Porto (CAUP), Universidade do Porto [Porto], Laboratoire d'Electronique et des Technologies de l'Information (CEA-LETI), Université Grenoble Alpes (UGA)-Direction de Recherche Technologique (CEA) (DRT (CEA)), INAF - Osservatorio Astronomico di Roma (OAR), SIM/IDL Faculdade de Ciências da Universidade de Lisboa (FCUL), University of Lisboa, 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), Institut für Astronomie, Universität Wien (IFA), Laboratoire Gemini (LG), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Groupe de Recherche en Astronomie et Astrophysique du Languedoc (GRAAL), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Instituto de Astrofisica de Canarias (IAC), Département Recherches Subatomiques (DRS-IPHC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), INAF - Osservatorio Astrofisico di Arcetri (OAA), Instituto Nacional de Engenharia, Tecnologia e Inovacco (INETI), European Southern Observatory (ESO), Department of Computer Science and Engineering [Bologna] (DISI), Università di Bologna [Bologna] (UNIBO), A. Moorwood, VSI collaboration, CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Friedrich-Schiller-Universität = Friedrich Schiller University Jena [Jena, Germany], COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS), Universidade do Porto, Commissariat à l'énergie atomique et aux énergies alternatives - Laboratoire d'Electronique et de Technologie de l'Information (CEA-LETI), Direction de Recherche Technologique (CEA) (DRT (CEA)), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS), Instituto Nacional de Engenharia, Tecnologia e Inovacao (INETI), Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Université Nice Sophia Antipolis (1965 - 2019) (UNS), Universidade do Porto = University of Porto, École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), and COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-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)

Subjects
Physics, Active galactic nucleus, Mode (statistics), Astrophysics::Instrumentation and Methods for Astrophysics, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Domain (software engineering), [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Stars, Interferometry, Wavelength, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract

8 pages. To be published in the proceedings of the ESO workshop "Science with the VLT in the ELT Era", held in Garching (Germany) on 8-12 October 2007, A. Moorwood editor.; Nowadays, compact sources relatively warm like surfaces of nearby stars, circumstellar environments of stars from early stages to the most evolved ones and surroundings of active galactic nuclei can be investigated at milli-arcsecond scales only with the VLT in its interferometric mode. We propose a spectro-imager, named VSI (VLTI spectro-imager), which is capable to probe these sources both over spatial and spectral scales in the near-infrared domain. This instrument will provide information complementary to what is obtained at the same time with ALMA at different wavelengths and the extreme large telescopes.

Published
2009
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12. PEGASE, an infrared interferometer to study stellar environments and low mass companions around nearby stars

Author

M. Ollivier, O. Absil, F. Allard, J.-P. Berger, P. Bordé, F. Cassaing, B. Chazelas, A. Chelli, O. Chesneau, V. Coudé du Foresto, D. Defrère, P. Duchon, P. Gabor, J. Gay, E. Herwats, S. Jacquinod, P. Kern, P. Kervella, J.-M. Le Duigou, A. Léger, B. Lopez, F. Malbet, D. Mourard, D. Pelat, G. Perrin, Y. Rabbia, D. Rouan, J.-M. Reiss, G. Rousset, F. Selsis, P. Stee, J. Surdej, Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-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), Laboratoire d'Étude des Phénomènes de Transfert et de l'Instantanéité : Agro-industrie et Bâtiment (LEPTIAB), Université de La Rochelle (ULR), 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), ONERA - The French Aerospace Lab [Châtillon], ONERA-Université Paris Saclay (COmUE), Laboratoire Hippolyte Fizeau (FIZEAU), 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), Laboratoire Bordelais de Recherche en Informatique (LaBRI), Université de Bordeaux (UB)-Centre National de la Recherche Scientifique (CNRS)-École Nationale Supérieure d'Électronique, Informatique et Radiocommunications de Bordeaux (ENSEIRB), Laboratoire Gemini (LG), 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)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'étude des Mécanismes de la recombinaison (LMR), Centre National de la Recherche Scientifique (CNRS), Departement d'Astrophysique Extragalactique et de Cosmologie (DAEC), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), 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'astrodynamique, d'astrophysique et d'aéronomie de bordeaux (L3AB), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Observatoire aquitain des sciences de l'univers (OASU), 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), Institut d'Astrophysique et de Géophysique [Liège], Université de Liège, Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), La Rochelle Université (ULR), Université Nice Sophia Antipolis (1965 - 2019) (UNS), Université de Bordeaux (UB)-École Nationale Supérieure d'Électronique, Informatique et Radiocommunications de Bordeaux (ENSEIRB)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), and Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Cosmic Vision, Infrared, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, 7. Clean energy, 010309 optics, 0103 physical sciences, 010303 astronomy & astrophysics, Low mass objects, Astrophysics::Galaxy Astrophysics, Physics, Spacecraft, business.industry, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy, Astronomy and Astrophysics, Interferometry, Stars, Space interferometry, 13. Climate action, Space and Planetary Science, Physics::Space Physics, Darwin (spacecraft), Astrophysics::Earth and Planetary Astrophysics, Nulling interferometry, business, Low Mass, Circumstellar habitable zone
Abstract

International audience; PEGASE is a mission dedicated to the exploration of the environment (including habitable zone) of young and solar-type stars (particularly those in the DARWIN catalogue) and the observation of low mass companions around nearby stars. It is a space interferometer project composed of three free flying spacecraft, respectively featuring two 40 cm siderostats and a beam combiner working in the visible and near infrared. It has been proposed to ESA as an answer to the first “Cosmic Vision” call for proposals, as an M mission. The concept also enables full-scale demonstration of space nulling interferometry operation for DARWIN.

Published
2009
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14. Observing Young Stellar Objects with Very Large Telescope Interferometer

Author

F. Malbet

Subjects
Physics, Very Large Telescope, Astronomical optical interferometry, Young stellar object, Intensity interferometer, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy, X-ray telescope, Interferometry, Planet, Astronomical interferometer, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract

One of the techniques used to probe the formation of stars and planets, is optical long baseline interferometry. This technique offers milli-arcsecond spatial resolution. The Very Large Telescope Interferometer (VLTI) has been built to offer this new observational facility to any astronomer. In this review, I detail the specificity of high angular resolution observations in the field of stellar and planetary formation. I present a short introduction to interferometry, followed by an extensive presentation of the VLTI. Finally I give some advice to those who would like to use the instruments of the VLTI.

Published
2007
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15. Optical configuration and analysis of the AMBER/VLTI instrument

Author

S. Robbe-Dubois, S. Lagarde, R. G. Petrov, F. Lisi, U. Beckmann, P. Antonelli, Y. Bresson, G. Martinot-Lagarde, A. Roussel, P. Salinari, M. Vannier, A. Chelli, M. Dugué, G. Duvert, S. Gennari, L. Glück, P. Kern, E. Le Coarer, F. Malbet, F. Millour, K. Perraut, P. Puget, F. Rantakyrö, E. Tatulli, G. Weigelt, G. Zins, M. Accardo, B. Acke, K. Agabi, E. Altariba, B. Arezki, E. Aristidi, C. Baffa, J. Behrend, T. Blöcker, S. Bonhomme, S. Busoni, F. Cassaing, J.-M. Clausse, J. Colin, C. Connot, L. Delage, A. Delboulbé, A. Domiciano de Souza, T. Driebe, P. Feautrier, D. Ferruzzi, T. Forveille, E. Fossat, R. Foy, D. Fraix-Burnet, A. Gallardo, E. Giani, C. Gil, A. Glentzlin, M. Heiden, M. Heininger, O. Hernandez Utrera, K.-H. Hofmann, D. Kamm, M. Kiekebusch, S. Kraus, D. Le Contel, J.-M. Le Contel, T. Lesourd, B. Lopez, M. Lopez, Y. Magnard, A. Marconi, G. Mars, P. Mathias, P. Mège, J.-L. Monin, D. Mouillet, D. Mourard, E. Nussbaum, K. Ohnaka, J. Pacheco, C. Perrier, Y. Rabbia, S. Rebattu, F. Reynaud, A. Richichi, A. Robini, M. Sacchettini, D. Schertl, M. Schöller, W. Solscheid, A. Spang, P. Stee, P. Stefanini, M. Tallon, I. Tallon-Bosc, D. Tasso, L. Testi, F. Vakili, O. von der Lühe, J.-C. Valtier, N. Ventura, Laboratoire Universitaire d'Astrophysique de Nice (LUAN), 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)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Gemini (LG), 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)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS), INAF - Osservatorio Astrofisico di Arcetri (OAA), Istituto Nazionale di Astrofisica (INAF), Max-Planck-Institut für Radioastronomie (MPIFR), Division technique INSU/SDU (DTI), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), European Southern Observatory (ESO), Institute of Astronomy [Leuven], Catholic University of Leuven - Katholieke Universiteit Leuven (KU Leuven), Laboratoire Hippolyte Fizeau (FIZEAU), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Galilée (Galilée), Laboratoire de Cosmologie, Astrophysique Stellaire & Solaire, de Planétologie et de Mécanique des Fluides (CASSIOPEE), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), 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, and 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)

Subjects
FOS: Physical sciences, Astrophysics, 01 natural sciences, Stability (probability), 010309 optics, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Optics, numerical, interferometers, instrumentation: high angular resolution, 0103 physical sciences, Visibility, 010303 astronomy & astrophysics, Physics, Basis (linear algebra), Spatial filter, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], business.industry, Emphasis (telecommunications), Astrophysics (astro-ph), Astronomy and Astrophysics, Differential phase, Transmission (telecommunications), Space and Planetary Science, methods : analytical, business, Realization (systems), laboratory
Abstract

This paper describes the design goals and engineering efforts that led to the realization of AMBER (Astronomical Multi BEam combineR) and to the achievement of its present performance. On the basis of the general instrumental concept, AMBER was decomposed into modules whose functions and detailed characteristics are given. Emphasis is put on the spatial filtering system, a key element of the instrument. We established a budget for transmission and contrast degradation through the different modules, and made the detailed optical design. The latter confirmed the overall performance of the instrument and defined the exact implementation of the AMBER optics. The performance was assessed with laboratory measurements and commissionings at the VLTI, in terms of spectral coverage and resolution, instrumental contrast higher than 0.80, minimum magnitude of 11 in K, absolute visibility accuracy of 1%, and differential phase stability of 1E-3 rad over one minute., Comment: 14 pages

Published
2007
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16. Near-infrared interferometry of eta Carinae with spectral resolutions of 1 500 and 12 000 using AMBER/VLTI

Author

G. Weigelt, S. Kraus, T. Driebe, R. G. Petrov, K.-H. Hofmann, F. Millour, O. Chesneau, D. Schertl, F. Malbet, D. J. Hillier, T. Gull, K. Davidson, A. Domiciano de Souza, P. Antonelli, U. Beckmann, Y. Bresson, A. Chelli, M. Dugué, G. Duvert, S. Gennari, L. Glück, P. Kern, S. Lagarde, E. Le Coarer, F. Lisi, K. Perraut, P. Puget, F. Rantakyrö, S. Robbe-Dubois, A. Roussel, E. Tatulli, G. Zins, M. Accardo, B. Acke, K. Agabi, E. Altariba, B. Arezki, E. Aristidi, C. Baffa, J. Behrend, T. Blöcker, S. Bonhomme, S. Busoni, F. Cassaing, J.-M. Clausse, J. Colin, C. Connot, A. Delboulbé, P. Feautrier, D. Ferruzzi, T. Forveille, E. Fossat, R. Foy, D. Fraix-Burnet, A. Gallardo, E. Giani, C. Gil, A. Glentzlin, M. Heiden, M. Heininger, O. Hernandez Utrera, D. Kamm, M. Kiekebusch, D. Le Contel, J.-M. Le Contel, T. Lesourd, B. Lopez, M. Lopez, Y. Magnard, A. Marconi, G. Mars, G. Martinot-Lagarde, P. Mathias, P. Mège, J.-L. Monin, D. Mouillet, D. Mourard, E. Nussbaum, K. Ohnaka, J. Pacheco, C. Perrier, Y. Rabbia, S. Rebattu, F. Reynaud, A. Richichi, A. Robini, M. Sacchettini, M. Schöller, W. Solscheid, A. Spang, P. Stee, P. Stefanini, M. Tallon, I. Tallon-Bosc, D. Tasso, L. Testi, F. Vakili, O. von der Lühe, J.-C. Valtier, M. Vannier, N. Ventura, K. Weis, M. Wittkowski, Max-Planck-Institut für Radioastronomie (MPIFR), Laboratoire Universitaire d'Astrophysique de Nice (LUAN), Université Nice Sophia Antipolis (... - 2019) (UNS), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-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), Laboratoire Gemini (LG), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Département Fresnel (FRESNEL), Observatoire de la Côte d'Azur, Laboratoire de Cosmologie, Astrophysique Stellaire & Solaire, de Planétologie et de Mécanique des Fluides (CASSIOPEE), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), INAF - Osservatorio Astrofisico di Arcetri (OAA), Istituto Nazionale di Astrofisica (INAF), European Southern Observatory (ESO), ONERA - The French Aerospace Lab [Châtillon], ONERA, Observatoire de la Côte d'Azur (OCA), Centre National de la Recherche Scientifique (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), 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), Association EURATOM-CEA (CEA/DSM/DRFC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Division technique INSU/SDU (DTI), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Astrophysique de Toulouse-Tarbes (LATT), Centre National de la Recherche Scientifique (CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Astrophysique Relativiste Théories Expériences Métrologie Instrumentation Signaux (ARTEMIS), PHOTONIQUE, XLIM (XLIM), Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)-Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS), 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)-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)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS), 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), ONERA-Université Paris Saclay (COmUE), 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), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-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), 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), 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), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Astrophysics::High Energy Astrophysical Phenomena, Continuum (design consultancy), Astrophysics, 01 natural sciences, 7. Clean energy, circumstellar matter, emission-line Be, outflows, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Atmospheric radiative transfer codes, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Emission spectrum, Spectral resolution, 010303 astronomy & astrophysics, infrared: stars, Astrophysics::Galaxy Astrophysics, Physics, Very Large Telescope, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, Near-infrared spectroscopy, Gamma ray, Astronomy and Astrophysics, Position angle, stars: individual: ηCarinae, winds, 13. Climate action, Space and Planetary Science, techniques: interferometric, stars: mass-loss
Abstract

Aims. We present the first NIR spectro-interferometry of the LBV ? Carinae. The observations were performed with the AMBER instrument of the ESO Very Large Telescope Interferometer (VLTI) using baselines from 42 to 89 m. The aim of this work is to study the wavelength dependence of ? Car's optically thick wind region with a high spatial resolution of 5 mas (11 AU) and high spectral resolution. Methods: The observations were carried out with three 8.2 m Unit Telescopes in the K-band. The raw data are spectrally dispersed interferograms obtained with spectral resolutions of 1500 (MR-K mode) and 12 000 (HR-K mode). The MR-K observations were performed in the wavelength range around both the He I 2.059 ?m and the Br? 2.166 ?m emission lines, the HR-K observations only in the Br? line region. Results: The spectrally dispersed AMBER interferograms allow the investigation of the wavelength dependence of the visibility, differential phase, and closure phase of ? Car. In the K-band continuum, a diameter of 4.0±0.2 mas (Gaussian FWHM, fit range 28-89 m baseline length) was measured for ? Car's optically thick wind region. If we fit Hillier et al. (2001, ApJ, 553, 837) model visibilities to the observed AMBER visibilities, we obtain 50% encircled-energy diameters of 4.2, 6.5 and 9.6 mas in the 2.17 ?m continuum, the He I, and the Br? emission lines, respectively. In the continuum near the Br? line, an elongation along a position angle of 120°±15° was found, consistent with previous VINCI/VLTI measurements by van Boekel et al. (2003, A&A, 410, L37). We compare the measured visibilities with predictions of the radiative transfer model of Hillier et al. (2001), finding good agreement. Furthermore, we discuss the detectability of the hypothetical hot binary companion. For the interpretation of the non-zero differential and closure phases measured within the Br? line, we present a simple geometric model of an inclined, latitude-dependent wind zone. Our observations support theoretical models of anisotropic winds from fast-rotating, luminous hot stars with enhanced high-velocity mass loss near the polar regions. Based on observations collected at the European Southern Observatory, Paranal, Chile, within the AMBER guaranteed time programme 074.A-9025 and the VLTI science demonstration programme 074.A-9024.

Published
2007
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17. Direct constraint on the distance of Gamma2 Velorum from AMBER/VLTI observations

Author

F. Millour, R. G. Petrov, O. Chesneau, D. Bonneau, L. Dessart, C. Bechet, I. Tallon-Bosc, M. Tallon, E. Thiébaut, F. Vakili, F. Malbet, D. Mourard, P. Antonelli, U. Beckmann, Y. Bresson, A. Chelli, M. Dugué, G. Duvert, S. Gennari, L. Glück, P. Kern, S. Lagarde, E. Le Coarer, F. Lisi, K. Perraut, P. Puget, F. Rantakyrö, S. Robbe-Dubois, A. Roussel, E. Tatulli, G. Weigelt, G. Zins, M. Accardo, B. Acke, K. Agabi, E. Altariba, B. Arezki, E. Aristidi, C. Baffa, J. Behrend, T. Blöcker, S. Bonhomme, S. Busoni, F. Cassaing, J.-M. Clausse, J. Colin, C. Connot, A. Delboulbé, A. Domiciano de Souza, T. Driebe, P. Feautrier, D. Ferruzzi, T. Forveille, E. Fossat, R. Foy, D. Fraix-Burnet, A. Gallardo, E. Giani, C. Gil, A. Glentzlin, M. Heiden, M. Heininger, O. Hernandez Utrera, K.-H. Hofmann, D. Kamm, M. Kiekebusch, S. Kraus, D. Le Contel, J.-M. Le Contel, T. Lesourd, B. Lopez, M. Lopez, Y. Magnard, A. Marconi, G. Mars, G. Martinot-Lagarde, P. Mathias, P. Mège, J.-L. Monin, D. Mouillet, E. Nussbaum, K. Ohnaka, J. Pacheco, C. Perrier, Y. Rabbia, S. Rebattu, F. Reynaud, A. Richichi, A. Robini, M. Sacchettini, D. Schertl, M. Schöller, W. Solscheid, A. Spang, P. Stee, P. Stefanini, D. Tasso, L. Testi, O. von der Lühe, J.-C. Valtier, M. Vannier, N. Ventura, 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), Laboratoire Universitaire d'Astrophysique de Nice (LUAN), 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)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Cosmologie, Astrophysique Stellaire & Solaire, de Planétologie et de Mécanique des Fluides (CASSIOPEE), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Gemini (LG), 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)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Steward Observatory (STEWARD OBSERVATORY), University of Arizona, Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), INAF - Osservatorio Astrofisico di Arcetri (OAA), Istituto Nazionale di Astrofisica (INAF), Max-Planck-Institut für Radioastronomie (MPIFR), European Southern Observatory (ESO), PHOTONIQUE, XLIM (XLIM), Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)-Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Astrophysique de Toulouse-Tarbes (LATT), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Division technique INSU/SDU (DTI), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), 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)-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), Observatoire de la Côte d'Azur (OCA), ONERA - The French Aerospace Lab [Châtillon], ONERA-Université Paris Saclay (COmUE), AMBER, Université Nice Sophia Antipolis (... - 2019) (UNS), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Université Côte d'Azur (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)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon), Centre National de la Recherche Scientifique (CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, 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), Centre National de la Recherche Scientifique (CNRS), ONERA, 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), Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), and Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3)

Subjects
Physics, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Astrophysics (astro-ph), FOS: Physical sciences, Astronomy and Astrophysics, Observable, Ranging, Astrophysics, Spectral bands, Position angle, 01 natural sciences, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Space and Planetary Science, 0103 physical sciences, Binary system, 010303 astronomy & astrophysics
Abstract

International audience; In this work, we present the first AMBER observations, of the Wolf-Rayet and O (WR+O) star binary system y² Velorum. The AMBER instrument was used with the telescopes UT2, UT3, and UT4 on baselines ranging from 46m to 85m. It delivered spectrally dispersed visibilities, as well as differential and closure phases, with a resolution R = 1500 in the spectral band 1.95-2.17 micron. We interpret these data in the context of a binary system with unresolved components, neglecting in a first approximation the wind-wind collision zone flux contribution. We show that the AMBER observables result primarily from the contribution of the individual components of the WR+O binary system. We discuss several interpretations of the residuals, and speculate on the detection of an additional continuum component, originating from the free-free emission associated with the wind-wind collision zone (WWCZ), and contributing at most to the observed K-band flux at the 5% level. The expected absolute separation and position angle at the time of observations were 5.1±0.9mas and 66±15° respectively. However, we infer a separation of 3.62+0.11-0.30 mas and a position angle of 73+9-11°. Our analysis thus implies that the binary system lies at a distance of 368+38-13 pc, in agreement with recent spectrophotometric estimates, but significantly larger than the Hipparcos value of 258+41-31 pc.

Published
2007
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19. Constraining the wind launching region in Herbig Ae stars: AMBER/VLTI spectroscopy of HD104237

Author

E. Tatulli, A. Isella, A. Natta, L. Testi, A. Marconi, F. Malbet, P. Stee, R. G. Petrov, F. Millour, A. Chelli, G. Duvert, P. Antonelli, U. Beckmann, Y. Bresson, M. Dugué, S. Gennari, L. Glück, P. Kern, S. Lagarde, E. Le Coarer, F. Lisi, K. Perraut, P. Puget, F. Rantakyrö, S. Robbe-Dubois, A. Roussel, G. Weigelt, G. Zins, M. Accardo, B. Acke, K. Agabi, E. Altariba, B. Arezki, E. Aristidi, C. Baffa, J. Behrend, T. Blöcker, S. Bonhomme, S. Busoni, F. Cassaing, J.-M. Clausse, J. Colin, C. Connot, A. Delboulbé, A. Domiciano de Souza, T. Driebe, P. Feautrier, D. Ferruzzi, T. Forveille, E. Fossat, R. Foy, D. Fraix-Burnet, A. Gallardo, E. Giani, C. Gil, A. Glentzlin, M. Heiden, M. Heininger, O. Hernandez Utrera, K.-H. Hofmann, D. Kamm, M. Kiekebusch, S. Kraus, D. Le Contel, J.-M. Le Contel, T. Lesourd, B. Lopez, M. Lopez, Y. Magnard, G. Mars, G. Martinot-Lagarde, P. Mathias, P. Mège, J.-L. Monin, D. Mouillet, D. Mourard, E. Nussbaum, K. Ohnaka, J. Pacheco, C. Perrier, Y. Rabbia, S. Rebattu, F. Reynaud, A. Richichi, A. Robini, M. Sacchettini, D. Schertl, M. Schöller, W. Solscheid, A. Spang, P. Stefanini, M. Tallon, I. Tallon-Bosc, D. Tasso, F. Vakili, O. von der Lühe, J.-C. Valtier, M. Vannier, N. Ventura, Laboratoire Hippolyte Fizeau (FIZEAU), Université Nice Sophia Antipolis (... - 2019) (UNS), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Galilée (Galilée), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Cosmologie, Astrophysique Stellaire & Solaire, de Planétologie et de Mécanique des Fluides (CASSIOPEE), Laboratoire Gemini (LG), 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), and Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, 010308 nuclear & particles physics, Astrophysics::High Energy Astrophysical Phenomena, Near-infrared spectroscopy, Astronomical unit, Continuum (design consultancy), Astrophysics (astro-ph), FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Stars, [SDU]Sciences of the Universe [physics], Space and Planetary Science, 0103 physical sciences, Peak intensity, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Spectral resolution, Spectroscopy, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Line (formation)
Abstract

We investigate the origin of the $\mathrm{Br}\gamma$ emission of the Herbig Ae star HD104237 on Astronomical Unit (AU) scales. Using AMBER/VLTI at a spectral resolution R=1500 spatially resolve the emission in both the BrGamma line and the adjacent continuum. The visibility does not vary between the continuum and the BrGamma line, even though the line is strongly detected in the spectrum, with a peak intensity 35% above the continuum. This demonstrates that the line and continuum emission have similar size scales. We assume that the K-band continuum excess originates in a ``puffed-up'' inner rim of the circumstellar disk, and discuss the likely origin of BrGamma. We conclude that this emission most likely arises from a compact disk wind, launched from a region 0.2-0.5 AU from the star, with a spatial extent similar to that of the near infrared continuum emission region, i.e, very close to the inner rim location., Comment: 4 pages, 2 figures, accepted in A&A

Published
2006
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20. The Palomar Testbed Interferometer

Author

M. M. Colavita, J. K. Wallace, B. E. Hines, Y. Gursel, F. Malbet, D. L. Palmer, X. P. Pan, M. Shao, J. W. Yu, A. F. Boden, P. J. Dumont, J. Gubler, C. D. Koresko, S. R. Kulkarni, B. F. Lane, D. W. Mobley, and G. T. van Belle

Subjects
Physics, Instrument control, business.industry, Testbed, Detector, Astrophysics (astro-ph), Astrophysics::Instrumentation and Methods for Astrophysics, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Astrometry, Metrology, Interferometry, Optical path, Optics, Palomar Testbed Interferometer, Space and Planetary Science, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, business, Astrophysics::Galaxy Astrophysics
Abstract

The Palomar Testbed Interferometer (PTI) is a long-baseline infrared interferometer located at Palomar Observatory, California. It was built as a testbed for interferometric techniques applicable to the Keck Interferometer. First fringes were obtained in July 1995. PTI implements a dual-star architecture, tracking two stars simultaneously for phase referencing and narrow-angle astrometry. The three fixed 40-cm apertures can be combined pair-wise to provide baselines to 110 m. The interferometer actively tracks the white-light fringe using an array detector at 2.2 um and active delay lines with a range of +/- 38 m. Laser metrology of the delay lines allows for servo control, and laser metrology of the complete optical path enables narrow-angle astrometric measurements. The instrument is highly automated, using a multiprocessing computer system for instrument control and sequencing., ApJ in Press (Jan 99) Fig 1 available from http://huey.jpl.nasa.gov/~bode/ptiPicture.html, revised duging copy edit

Published
1998

21. Detecting Disks Around Young Stellar Objects With Infrared Interferometers

Author

F. Malbet

Subjects
Physics, Interferometric visibility, Infrared, Young stellar object, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy, Astrophysics::Cosmology and Extragalactic Astrophysics, Interferometry, Accretion disc, Young star, Astronomical interferometer, Astrophysics::Solar and Stellar Astrophysics, Spectral energy distribution, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract

We have simulated accretion disks around young stellar objects with the aim of computing interferometric visibility curves for present and soon-to-be infared interferometers. We demonstrate that such disks are detectable with an interferometric layout like the VISA configuration of the VLTI or with present infrared interferometers with improved sensitivity

Published
1997
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22. VLTI Observing Preparation Sequence

Author

F. Malbet

Subjects
Physics, Very Large Telescope, Astrophysics::Instrumentation and Methods for Astrophysics, General Engineering, Astronomy, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Optical telescope, law.invention, Primary mirror, Telescope, Data flow diagram, Interferometry, Space and Planetary Science, Observatory, law, Astronomical interferometer, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract

Optical interferometers are instruments that combine the light coming from separated optical telescopes in order to get information with the spatial resolution of the telescope array. One of the major interferometer is the Very Large Telescope Interferometer (VLTI) . To observe an astronomical target with the VLTI, like with any other interferometers, one needs to carefully prepare the observations because of the numerous parameters to be fixed. In addition, the VLTI is being developed in the framework of the data flow system created for the Very Large telescopes (VLT) at the European Southern Observatory (ESO) . I recall the philosophy of the ESO/VLT data flow system and its adaptation to the VLTI data and then I describe the various steps required to prepare a VLTI observation. Finally, I illustrate the various steps of this preparation with an example focused in the observations of the young binary system Z CMa.

Published
2003
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23. Exercise #3 Signal-to-noise calculations with the AMBER & MIDI instruments

Author

F. Malbet

Subjects
Physics, MIDI, business.industry, Visibility (geometry), General Engineering, Astronomy and Astrophysics, computer.file_format, Theoretical physics, Software, Space and Planetary Science, Order (business), Error bar, business, Algorithm, computer
Abstract

The objective of this exercise is to learn how to compute error bars on visibility estimations computed with the ASPRO software in order to investigate the feasibility of an observations with the VLTI.

Published
2003
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24. Exercise #5 Observing program preparation

Author

F. Malbet, Guy Perrin, 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), Pôle Astronomie du LESIA, 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)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris

Subjects
Physics, Work (electrical), Space and Planetary Science, General Engineering, Systems engineering, Astronomy and Astrophysics, Observable, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract

This exercise is aimed at building a complete observing program for the VLTI. It consists in defining the scientific rationale and immediate objectives, ensure that the target are observable, define the VLTI configuration, model the astrophyiscal source and estimate the expected signal-to-noise ratio. At the end one should be able to define the total time requested and the final configuration. This exercise is a simulation of the work required to eventually request time on the VLTI.

Published
2003
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25. First AMBER/VLTI Observations of Hot Massive Stars

Author

R. G. Petrov, F. Millour, O. Chesneau, G. Weigelt, D. Bonneau, Ph. Stee, S. Kraus, D. Mourard, A. Meilland, M. Vannier, F. Malbet, F. Lisi, P. Antonelli, P. Kern, U. Beckmann, S. Lagarde, K. Perraut, S. Gennari, E. Le Coarer, Th. Driebe, M. Accardo, S. Robbe-Dubois, K. Ohnaka, S. Busoni, A. Roussel, G. Zins, J. Behrend, D. Ferruzi, Y. Bresson, G. Duvert, E. Nussbaum, A. Marconi, Ph. Feautrier, M. Dugué, A. Chelli, E. Tatulli, M. Heininger, A. Delboulbe, S. Bonhomme, D. Schertl, L. Testi, Ph. Mathias, J. -L. Monin, L. Gluck, K. H. Hofmann, P. Salinari, P. Puget, J. M. Clausse, D. Fraix-Burnet, R. Foy, and A. Isella

Subjects
Physics, Astrophysics::High Energy Astrophysical Phenomena, Near-infrared spectroscopy, Astrophysics::Instrumentation and Methods for Astrophysics, Astrophysics, 01 natural sciences, 010309 optics, Interferometry, Stars, Wolf–Rayet star, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Spectral resolution, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics
Abstract

AMBER is the first near infrared focal instrument of the VLTI. It combines three telescopes and produces spectrally resolved interferometric measures. This paper discusses some preliminary results of the first scientific observations of AMBER with three Unit Telescopes at medium (1500) and high (12000) spectral resolution. We derive a first set of constraints on the structure of the circumstellar material around the Wolf Rayet Gamma2 Velorum and the LBV Eta Carinae.

26. Darwin--a mission to detect and search for life on extrasolar planets.

Author

Cockell CS, Léger A, Fridlund M, Herbst TM, Kaltenegger L, Absil O, Beichman C, Benz W, Blanc M, Brack A, Chelli A, Colangeli L, Cottin H, Coudé du Foresto F, Danchi WC, Defrère D, den Herder JW, Eiroa C, Greaves J, Henning T, Johnston KJ, Jones H, Labadie L, Lammer H, Launhardt R, Lawson P, Lay OP, LeDuigou JM, Liseau R, Malbet F, Martin SR, Mawet D, Mourard D, Moutou C, Mugnier LM, Ollivier M, Paresce F, Quirrenbach A, Rabbia YD, Raven JA, Rottgering HJ, Rouan D, Santos NC, Selsis F, Serabyn E, Shibai H, Tamura M, Thiébaut E, Westall F, and White GJ

Subjects
Astronomy, Bayes Theorem, Image Processing, Computer-Assisted, Spacecraft, Spectrophotometry, Infrared, Stars, Celestial, Exobiology methods, Extraterrestrial Environment, Origin of Life, Planets, Space Flight
Abstract

The discovery of extrasolar planets is one of the greatest achievements of modern astronomy. The detection of planets that vary widely in mass demonstrates that extrasolar planets of low mass exist. In this paper, we describe a mission, called Darwin, whose primary goal is the search for, and characterization of, terrestrial extrasolar planets and the search for life. Accomplishing the mission objectives will require collaborative science across disciplines, including astrophysics, planetary sciences, chemistry, and microbiology. Darwin is designed to detect rocky planets similar to Earth and perform spectroscopic analysis at mid-infrared wavelengths (6-20 mum), where an advantageous contrast ratio between star and planet occurs. The baseline mission is projected to last 5 years and consists of approximately 200 individual target stars. Among these, 25-50 planetary systems can be studied spectroscopically, which will include the search for gases such as CO(2), H(2)O, CH(4), and O(3). Many of the key technologies required for the construction of Darwin have already been demonstrated, and the remainder are estimated to be mature in the near future. Darwin is a mission that will ignite intense interest in both the research community and the wider public.

Published
2009
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27. The building blocks of planets within the 'terrestrial' region of protoplanetary disks.

Author

van Boekel R, Min M, Leinert Ch, Waters LB, Richichi A, Chesneau O, Dominik C, Jaffe W, Dutrey A, Graser U, Henning T, de Jong J, Köhler R, de Koter A, Lopez B, Malbet F, Morel S, Paresce F, Perrin G, Preibisch T, Przygodda F, Schöller M, and Wittkowski M

Abstract

Our Solar System was formed from a cloud of gas and dust. Most of the dust mass is contained in amorphous silicates, yet crystalline silicates are abundant throughout the Solar System, reflecting the thermal and chemical alteration of solids during planet formation. (Even primitive bodies such as comets contain crystalline silicates.) Little is known about the evolution of the dust that forms Earth-like planets. Here we report spatially resolved detections and compositional analyses of these building blocks in the innermost two astronomical units of three proto-planetary disks. We find the dust in these regions to be highly crystallized, more so than any other dust observed in young stars until now. In addition, the outer region of one star has equal amounts of pyroxene and olivine, whereas the inner regions are dominated by olivine. The spectral shape of the inner-disk spectra shows surprising similarity with Solar System comets. Radial-mixing models naturally explain this resemblance as well as the gradient in chemical composition. Our observations imply that silicates crystallize before any terrestrial planets are formed, consistent with the composition of meteorites in the Solar System.

Published
2004
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28. The central dusty torus in the active nucleus of NGC 1068.

Author

Jaffe W, Meisenheimer K, Röttgering HJ, Leinert Ch, Richichi A, Chesneau O, Fraix-Burnet D, Glazenborg-Kluttig A, Granato GL, Graser U, Heijligers B, Köhler R, Malbet F, Miley GK, Paresce F, Pel JW, Perrin G, Przygodda F, Schoeller M, Sol H, Waters LB, Weigelt G, Woillez J, and De Zeeuw PT

Abstract

Active galactic nuclei (AGNs) display many energetic phenomena--broad emission lines, X-rays, relativistic jets, radio lobes--originating from matter falling onto a supermassive black hole. It is widely accepted that orientation effects play a major role in explaining the observational appearance of AGNs. Seen from certain directions, circum-nuclear dust clouds would block our view of the central powerhouse. Indirect evidence suggests that the dust clouds form a parsec-sized torus-shaped distribution. This explanation, however, remains unproved, as even the largest telescopes have not been able to resolve the dust structures. Here we report interferometric mid-infrared observations that spatially resolve these structures in the galaxy NGC 1068. The observations reveal warm (320 K) dust in a structure 2.1 parsec thick and 3.4 parsec in diameter, surrounding a smaller hot structure. As such a configuration of dust clouds would collapse in a time much shorter than the active phase of the AGN, this observation requires a continual input of kinetic energy to the cloud system from a source coexistent with the AGN.

Published
2004
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29. Integrated Optics for Astronomical Interferometry. III. Optical Validation of a Planar Optics Two-Telescope Beam Combiner.

Author

Haguenauer P, Berger JP, Rousselet-Perraut K, Kern P, Malbet F, Schanen-Duport I, and Benech P

Abstract

The optical characterization of a fiber-connected planar optics beam combiner dedicated to astronomical interferometry for two telescopes is presented. The beam combiner, fully integrated on a single 5 mm x 40 mm glass chip, is tested as the central part of an astronomical instrument. The single-mode waveguides are made by silver-ion-exchange technology upon glass substrates and provide spatial filtering, which improves the visibility measurement accuracy by selecting only the fundamental mode of the beams at the telescope focal plane. A global optical throughput of 43% is measured, and the sources of losses are identified and examined in detail. Solutions for improving this throughput are proposed. High and stable contrasts are obtained with a 1.55-mum laser diode (?96%) and with a white-light source (~92%) in the astronomical H filter (1.43 mum; 1.77 mum). The need for accurate control of differential instrumental polarization is demonstrated. In this context the intrinsic polarization-maintaining property of the planar optics component is characterized. This validation of the important potential uses of integrated planar optics should be valuable for future design of optical telescope arrays.

Published
2000
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