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1. Progress of the CHARA/SPICA project

Author

Pannetier, C., Mourard, D., Berio, P., Cassaing, F., Allouche, F., Anugu, N., Bailet, C., Brummelaar, T. ten, Dejonghe, J., Gies, D., Jocou, L., Kraus, S., Lacour, S., Lagarde, S., Bouquin, J. B. Le, Lecron, D., Monnier, J., Nardetto, N., Patru, F., Perraut, K., Petrov, R., Rousseau, S., Stee, P., Sturmann, J., and Sturmann, L.

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

CHARA/SPICA (Stellar Parameters and Images with a Cophased Array) is currently being developed at Observatoire de la C\^ote d'Azur. It will be installed at the visible focus of the CHARA Array by the end of 2021. It has been designed to perform a large survey of fundamental stellar parameters with, in the possible cases, a detailed imaging of the surface or environment of stars. To reach the required precision and sensitivity, CHARA/SPICA combines a low spectral resolution mode R = 140 in the visible and single-mode fibers fed by the AO stages of CHARA. This setup generates additional needs before the interferometric combination: the compensation of atmospheric refraction and longitudinal dispersion, and the fringe stabilization. In this paper, we present the main features of the 6-telescopes fibered visible beam combiner (SPICA-VIS) together with the first laboratory and on-sky results of the fringe tracker (SPICA-FT). We describe also the new fringe-tracker simulator developed in parallel to SPICA-FT.

Published
2021
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2. The GRAVITY fringe tracker

Author

Lacour, S., Dembet, R., Abuter, R., Fedou, P., Perrin, G., Choquet, E., Pfuhl, O., Eisenhauer, F., Woillez, J., Cassaing, F., Wieprecht, E., Ott, T., Wiezorrek, E., Wolff, B., Ramirez, A., Haubois, X., Perraut, K., Straubmeier, C., Brandner, W., and Amorim, A.

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

The GRAVITY instrument has been commissioned on the VLTI during 2016 and is now available to the astronomical community. It is the first optical interferometer capable of observing sources as faint as magnitude 19 in K-band. This is possible thanks to the fringe tracker which compensates the differential piston based on measurements of a brighter off-axis astronomical reference source. The goal of this paper is to consign the main developments made in the context of the GRAVITY fringe tracker. This could serve as basis for future fringe tracking systems. The paper therefore covers all aspects of the fringe tracker, from hardware, to control software and on-sky observations. Special emphasis is placed on the interaction between the group delay controller and the phase delay controller. The group delay control loop is a simple but robust integrator. The phase delay controller is a state-space control loop based on an auto-regressive representation of the atmospheric and vibrational perturbations. A Kalman filter provides optimal determination of the state of the system. The fringe tracker shows good tracking performance on sources with coherent K magnitudes of 11 on the UTs and 9.5 on the ATs. It can track fringes with an SNR level of 1.5 per DIT, limited by photon and background noises. On the ATs, during good seeing conditions, the optical path delay residuals can be as low as 75 nm root mean square. On the UTs, the performance is limited to around 250 nm because of structural vibrations., Comment: Published in A&A. 18 pages

Published
2019
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3. GRAVITY chromatic imaging of Eta Car's core

Author

GRAVITY Collaboration, Sanchez-Bermudez, J., Weigelt, G., Bestenlehner, J. M., Kervella, P., Brandner, W., Henning, Th., Müller, A., Perrin, G., Pott, J. -U., Schöller, M., van Boekel, R., Abuter, R., Accardo, M., Amorim, A., Anugu, N., Ávila, G., Benisty, M., Berger, J. P., Blind, N., Bonnet, H., Bourget, P., Brast, R., Buron, A., Cantalloube, F., Garatti, A. Caratti o, Cassaing, F., Chapron, F., Choquet, E., Clénet, Y., Collin, C., Foresto, V. Coudé du, de Wit, W., de Zeeuw, T., Deen, C., Delplancke-Ströbele, F., Dembet, R., Derie, F., Dexter, J., Duvert, G., Ebert, M., Eckart, A., Eisenhauer, F., Esselborn, M., Fédou, P., Garcia, P. J. V., Dabo, C. E. Garcia, Lopez, R. Garcia, Gao, F., Gendron, E., Genzel, R., Gillessen, S., Haubois, X., Haug, M., Haussmann, F., Hippler, S., Horrobin, M., Huber, A., Hubert, Z., Hubin, N., Hummel, C. A., Jakob, G., Jochum, L., Jocou, L., Karl, M., Kaufer, A., Kellner, S., Kendrew, S., Kern, L., Kiekebusch, M., Klein, R., Kolb, J., Kulas, M., Lacour, S., Lapeyrère, V., Lazareff, B., Bouquin, J. -B. Le, Léna, P., Lenzen, R., Levêque, S., Lippa, M., Magnard, Y., Mehrgan, L., Mellein, M., Mérand, A., Moreno-Ventas, J., Moulin, T., Müller, E., Müller, F., Neumann, U., Oberti, S., Ott, T., Pallanca, L., Panduro, J., Pasquini, L., Paumard, T., Percheron, I., Perraut, K., Petrucci, P. -O., Pflüger, A., Pfuhl, O., Duc, T. P., Plewa, P. M., Popovic, D., Rabien, S., Ramirez, A., Ramos, J., Rau, C., Riquelme, M., Rodríguez-Coira, G., Rohloff, R. -R., Rosales, A., Rousset, G., Scheithauer, S., Schuhler, N., Spyromilio, J., Straub, O., Straubmeier, C., Sturm, E., Suarez, M., Tristram, K. R. W., Ventura, N., Vincent, F., Waisberg, I., Wank, I., Widmann, F., Wieprecht, E., Wiest, M., Wiezorrek, E., Wittkowski, M., Woillez, J., Wolff, B., Yazici, S., Ziegler, D., and Zins, G.

Subjects
Astrophysics - Solar and Stellar Astrophysics
Abstract

Eta Car is one of the most intriguing luminous blue variables in the Galaxy. Observations and models at different wavelengths suggest a central binary with a 5.54 yr period residing in its core. 2D and 3D radiative transfer and hydrodynamic simulations predict a primary with a dense and slow stellar wind that interacts with the faster and lower density wind of the secondary. The wind-wind collision scenario suggests that the secondary's wind penetrates the primary's wind creating a low-density cavity in it, with dense walls where the two winds interact. We aim to trace the inner ~5-50 au structure of Eta Car's wind-wind interaction, as seen through BrG and, for the first time, through the He I 2s-2p line. We have used spectro-interferometric observations with GRAVITY at the VLTI. Our modeling of the continuum allows us to estimate its FWHM angular size close to 2 mas and an elongation ratio of 1.06 +/- 0.05 over a PA = 130 +/- 20 deg. Our CMFGEN modeling helped us to confirm that the role of the secondary should be taken into account to properly reproduce the observed BrG and He I lines. Chromatic images across BrG reveal a southeast arc-like feature, possibly associated to the hot post-shocked winds flowing along the cavity wall. The images of He I 2s-2p served to constrain the 20 mas structure of the line-emitting region. The observed morphology of He I suggests that the secondary is responsible for the ionized material that produces the line profile. Both the BrG and the He I 2s-2p maps are consistent with previous hydrodynamical models of the colliding wind scenario. Future dedicated simulations together with an extensive interferometric campaign are necessary to refine our constraints on the wind and stellar parameters of the binary, which finally will help us predict the evolutionary path of Eta Car., Comment: 32 pages, 27 figures (14 in the main body, 13 in the appendices), accepted for publication in AA

Published
2018
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4. Large amplitude tip/tilt estimation by geometric diversity for multiple-aperture telescopes

Author

Vievard, S., Cassaing, F., and Mugnier, L. M.

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

A novel method nicknamed ELASTIC is proposed for the alignment of multiple-aperture telescopes, in particular segmented telescopes. It only needs the acquisition of two diversity images of an unresolved source, and is based on the computation of a modified, frequency-shifted, cross-spectrum. It provides a polychromatic large range tip/tilt estimation with the existing hardware and an inexpensive noniterative unsupervised algorithm. Its performance is studied and optimized by means of simulations. They show that with 5000 photo-electrons/sub-aperture/frame and 1024x1024 pixel images, residues are within the capture range of interferometric phasing algorithms such as phase diversity. The closed-loop alignment of a 6 sub-aperture mirror provides an experimental demonstration of the effectiveness of the method. Author accepted version. Final version is Copyright 2017 Optical Society of America. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modifications of the content of this paper are prohibited., Comment: Final version: https://www.osapublishing.org/josaa/abstract.cfm?uri=josaa-34-8-1272

Published
2017
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5. First Light for GRAVITY: Phase Referencing Optical Interferometry for the Very Large Telescope Interferometer

Author

GRAVITY Collaboration, Abuter, R., Accardo, M., Amorim, A., Anugu, N., Ávila, G., Azouaoui, N., Benisty, M., Berger, J. P., Blind, N., Bonnet, H., Bourget, P., Brandner, W., Brast, R., Buron, A., Burtscher, L., Cassaing, F., Chapron, F., Choquet, É., Clénet, Y., Collin, C., Foresto, V. Coudé du, de Wit, W., de Zeeuw, P. T., Deen, C., Delplancke-Ströbele, F., Dembet, R., Derie, F., Dexter, J., Duvert, G., Ebert, M., Eckart, A., Eisenhauer, F., Esselborn, M., Fédou, P., Finger, G., Garcia, P., Dabo, C. E. Garcia, Lopez, R. Garcia, Gendron, E., Genzel, R., Gillessen, S., Gonte, F., Gordo, P., Grould, M., Grözinger, U., Guieu, S., Haguenauer, P., Hans, O., Haubois, X., Haug, M., Haussmann, F., Henning, Th., Hippler, S., Horrobin, M., Huber, A., Hubert, Z., Hubin, N., Hummel, C. A., Jakob, G., Janssen, A., Jochum, L., Jocou, L., Kaufer, A., Kellner, S., Kern, L., Kervella, P., Kiekebusch, M., Klein, R., Kok, Y., Kolb, J., Kulas, M., Lacour, S., Lapeyrère, V., Lazareff, B., Bouquin, J. -B. Le, Lèna, P., Lenzen, R., Lévêque, S., Lippa, M., Magnard, Y., Mehrgan, L., Mellein, M., Mérand, A., Moreno-Ventas, J., Moulin, T., Müller, E., Müller, F., Neumann, U., Oberti, S., Ott, T., Pallanca, L., Panduro, J., Pasquini, L., Paumard, T., Percheron, I., Perraut, K., Perrin, G., Pflüger, A., Pfuhl, O., Duc, T. Phan, Plewa, P. M., Popovic, D., Rabien, S., Ramírez, A., Ramos, J., Rau, C., Riquelme, M., Rohloff, R. -R., Rousset, G., Sanchez-Bermudez, J., Scheithauer, S., Schöller, M., Schuhler, N., Spyromilio, J., Straubmeier, C., Sturm, E., Suarez, M., Tristram, K. R. W., Ventura, N., Vincent, F., Waisberg, I., Wank, I., Weber, J., Wieprecht, E., Wiest, M., Wiezorrek, E., Wittkowski, M., Woillez, J., Wolff, B., Yazici, S., Ziegler, D., and Zins, G.

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

GRAVITY is a new instrument to coherently combine the light of the European Southern Observatory Very Large Telescope Interferometer to form a telescope with an equivalent 130 m diameter angular resolution and a collecting area of 200 m$^2$. The instrument comprises fiber fed integrated optics beam combination, high resolution spectroscopy, built-in beam analysis and control, near-infrared wavefront sensing, phase-tracking, dual beam operation and laser metrology [...]. This article gives an overview of GRAVITY and reports on the performance and the first astronomical observations during commissioning in 2015/16. We demonstrate phase tracking on stars as faint as m$_K$ ~ 10 mag, phase-referenced interferometry of objects fainter than m$_K$ ~ 15 mag with a limiting magnitude of m$_K$ ~ 17 mag, minute long coherent integrations, a visibility accuracy of better than 0.25 %, and spectro-differential phase and closure phase accuracy better than 0.5{\deg}, corresponding to a differential astrometric precision of better than 10 microarcseconds ({\mu}as). The dual-beam astrometry, measuring the phase difference of two objects with laser metrology, is still under commissioning. First observations show residuals as low as 50 {\mu}as when following objects over several months. We illustrate the instrument performance with the observations of archetypical objects for the different instrument modes. Examples include the Galactic Center supermassive black hole and its fast orbiting star S2 for phase referenced dual beam observations and infrared wavefront sensing, the High Mass X-Ray Binary BP Cru and the Active Galactic Nucleus of PDS 456 for few {\mu}as spectro-differential astrometry, the T Tauri star S CrA for a spectro-differential visibility analysis, {\xi} Tel and 24 Cap for high accuracy visibility observations, and {\eta} Car for interferometric imaging with GRAVITY., Comment: Accepted for publication in A&A, 23 pages, 23 figures, corresponding author: F. Eisenhauer

Published
2017
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6. PROVIDENCE: toward a 2.5m adaptive telescope for optical space domain awareness (but not only…)

Author

Jackson, Kathryn J., Schmidt, Dirk, Vernet, Elise, Petit, C., Fusco, T., Védrenne, N., Sauvage, J.-F., Leplat, G., Barbon-Dubosc, D., Adami, C., Advani, T., Blanc, P.-E., Bonnefois, A., Basa, S., Cassaing, F., Coiro, E., De La Barrière, F., Dolon, F., Fetick, R., Ferrari, M., Floriot, J., Frederick, Y.-M., Gustave, F., Haensler, P.-E., Heritier, C. T., Hespel, L., Jouve, P., Michau, V., Mugnier, L., Neichel, B., Tricoli, U., and Vernazza, P.

Published
2024
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7. GRAVITY: a four-telescope beam combiner instrument for the VLTI

Author

Gillessen, S., Eisenhauer, F., Perrin, G., Brandner, W., Straubmeier, C., Perraut, K., Amorim, A., Schöller, M., Araujo-Hauck, C., Bartko, H., Baumeister, H., Berger, J. -P., Carvas, P., Cassaing, F., Chapron, F., Choquet, E., Clenet, Y., Collin, C., Eckart, A., Fedou, P., Fischer, S., Gendron, E., Genzel, R., Gitton, P., Gonte, F., Gräter, A., Haguenauer, P., Haug, M., Haubois, X., Henning, T., Hippler, S., Hofmann, R., Jocou, L., Kellner, S., Kervella, P., Klein, R., Kudryavtseva, N., Lacour, S., Lapeyrere, V., Laun, W., Lena, P., Lenzen, R., Lima, J., Moch, D., Moratschke, D., Moulin, T., Naranjo, V., Neumann, U., Nolot, A., Paumard, T., Pfuhl, O., Rabien, S., Ramos, J., Rees, J. M., Rohloff, R. -R., Rouan, D., Rousset, G., Sevin, A., Thiel, M., Wagner, K., Wiest, M., Yazici, S., and Ziegler, D.

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

GRAVITY is an adaptive optics assisted Beam Combiner for the second generation VLTI instrumentation. The instrument will provide high-precision narrow-angle astrometry and phase-referenced interferometric imaging in the astronomical K-band for faint objects. We describe the wide range of science that will be tackled with this instrument, highlighting the unique capabilities of the VLTI in combination with GRAVITY. The most prominent goal is to observe highly relativistic motions of matter close to the event horizon of Sgr A*, the massive black hole at center of the Milky Way. We present the preliminary design that fulfils the requirements that follow from the key science drivers: It includes an integrated optics, 4-telescope, dual feed beam combiner operated in a cryogenic vessel; near-infrared wavefrontsensing adaptive optics; fringe-tracking on secondary sources within the field of view of the VLTI and a novel metrology concept. Simulations show that 10 {\mu}as astrometry within few minutes is feasible for a source with a magnitude of mK = 15 like Sgr A*, given the availability of suitable phase reference sources (mK = 10). Using the same setup, imaging of mK = 18 stellar sources in the interferometric field of view is possible, assuming a full night of observations and the corresponding UV coverage of the VLTI., Comment: 20 pages, Proceedings SPIE Astronomical Telescopes and Instrumentation Conference 2010

Published
2010
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8. GRAVITY: getting to the event horizon of Sgr A*

Author

Eisenhauer, F., Perrin, G., Brandner, W., Straubmeier, C., Richichi, A., Gillessen, S., Berger, J. P., Hippler, S., Eckart, A., Schoeller, M., Rabien, S., Cassaing, F., Lenzen, R., Thiel, M., Clenet, Y., Ramos, J. R., Kellner, S., Fedou, P., Baumeister, H., Hofmann, R., Gendron, E., Boehm, A., Bartko, H., Haubois, X., Klein, R., Dodds-Eden, K., Houairi, K., Hormuth, F., Graeter, A., Jocou, L., Naranjo, V., Genzel, R., Kervella, P., Henning, T., Hamaus, N., Lacour, S., Neumann, U., Haug, M., Malbet, F., Laun, W., Kolmeder, J., Paumard, T., Rohloff, R. -R., Pfuhl, O., Perraut, K., Ziegleder, J., Rouan, D., and Rousset, G.

Subjects
Astrophysics
Abstract

We present the second-generation VLTI instrument GRAVITY, which currently is in the preliminary design phase. GRAVITY is specifically designed to observe highly relativistic motions of matter close to the event horizon of Sgr A*, the massive black hole at center of the Milky Way. We have identified the key design features needed to achieve this goal and present the resulting instrument concept. It includes an integrated optics, 4-telescope, dual feed beam combiner operated in a cryogenic vessel; near infrared wavefront sensing adaptive optics; fringe tracking on secondary sources within the field of view of the VLTI and a novel metrology concept. Simulations show that the planned design matches the scientific needs; in particular that 10 microarcsecond astrometry is feasible for a source with a magnitude of K=15 like Sgr A*, given the availability of suitable phase reference sources., Comment: 13 pages, 11 figures, to appear in the conference proceedings of SPIE Astronomical Instrumentation, 23-28 June 2008, Marseille, France

Published
2008
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9. Direct constraint on the distance of y2 Velorum from AMBER/VLTI observations

Author

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

Subjects
Astrophysics
Abstract

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
2006
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10. GRAVITY: Microarcsecond Astrometry and Deep Interferometric Imaging with the VLT

Author

Eisenhauer, F., Perrin, G., Brandner, W., Straubmeier, C., Böhm, A., Baumeister, H., Cassaing, F., Clénet, Y., Dodds-Eden, K., Eckart, A., Gendron, E., Genzel, R., Gillessen, S., Gräter, A., Gueriau, C., Hamaus, N., Haubois, X., Haug, M., Henning, T., Hippler, S., Hofmann, R., Hormuth, F., Houairi, K., Kellner, S., Kervella, P., Klein, R., Kolmeder, J., Laun, W., Léna, P., Lenzen, R., Marteaud, M., Naranjo, V., Neumann, U., Paumard, T., Rabien, S., Ramos, J. R., Reess, J. M., Rohloff, R.-R., Rouan, D., Rousset, G., Ruyet, B., Sevin, A., Thiel, M., Ziegleder, J., Ziegler, D., Burton, W. B., editor, Christensen, Lars Lindberg, editor, and Moorwood, Alan, editor

Published
2009
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11. GENIE: a Ground-Based European Nulling Instrument at ESO Very Large Telescope Interferometer

Author

Gondoin, P., Hartog, R. den, Fridlund, M., Fabry, P., Stankov, A., Peacock, A., Volonte, S., Puech, F., Delplancke, F., Gitton, P., Glindemann, A., Paresce, F., Richichi, A., Barillot, M., Absil, O., Cassaing, F., Coudédu Foresto, V., Kervella, P., Perrin, G., Ruilier, C., Flatscher, R., Bokhove, H., Ergenzinger, K., Quirrenbach, A., Wallner, O., Alves, J., Herbst, T., Mourard, D., Neuhäuser, R., Ségransan, D., Waters, R., White, G.J., Leibundgut, Bruno, editor, Richichi, A., editor, Delplancke, F., editor, Paresce, F., editor, and Chelli, A., editor

Published
2008
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12. Multiple-beam Fringe Tracking for the VLTI

Author

Cassaing, F., Baron, F., Mocoeur, I., Mugnier, L.M., Rousset, G., Sorrente, B., Leibundgut, Bruno, editor, Richichi, A., editor, Delplancke, F., editor, Paresce, F., editor, and Chelli, A., editor

Published
2008
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15. GRAVITY: Astrometry on the galactic center and beyond

Author

Bartko, H., Perrin, G., Brandner, W., Straubmeier, C., Richichi, A., Gillessen, S., Paumard, T., Hippler, S., Eckart, A., Schöller, M., Eisenhauer, F., Haubois, X., Lenzen, R., Rabien, S., Clénet, Y., Ramos, J.R., Thiel, M., Berger, J.P., Baumeister, H., Kellner, S., Cassaing, F., Böhm, A., Hofmann, R., Gendron, E., Klein, R., Dodds-Eden, K., Houairi, K., Hormuth, F., Gräter, A., Kervella, P., Naranjo, V., Genzel, R., Fédou, P., Henning, T., Hamaus, N., Jocou, L., Neumann, U., Haug, M., Lacour, S., Laun, W., Kolmeder, J., Malbet, F., Rohloff, R.-R., Pfuhl, O., Perraut, K., Ziegleder, J., Rouan, D., Rousset, G., Amorim, A., and Lima, J.

Published
2009
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16. Performance analysis of an adaptive optics based optical feeder link ground station

Author

Védrenne, N., primary, Petit, C., additional, Montmerle-Bonnefois, A., additional, Lim, C. B., additional, Conan, Jean-Marc, additional, Paillier, L., additional, Velluet, M.-T., additional, Caillault, K., additional, Gustave, F., additional, Durecu, A., additional, Michau, V., additional, Cassaing, F., additional, Meimon, S., additional, and Montri, J., additional

Published
2021
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17. PEGASE, an infrared interferometer to study stellar environments and low mass companions around nearby stars

Author

Ollivier, M., Absil, O., Allard, F., Berger, J.-P., Bordé, P., Cassaing, F., Chazelas, B., Chelli, A., Chesneau, O., Coudé du Foresto, V., Defrère, D., Duchon, P., Gabor, P., Gay, J., Herwats, E., Jacquinod, S., Kern, P., Kervella, P., Le Duigou, J.-M., Léger, A., Lopez, B., Malbet, F., Mourard, D., Pelat, D., Perrin, G., Rabbia, Y., Rouan, D., Reiss, J.-M., Rousset, G., Selsis, F., Stee, P., and Surdej, J.

Published
2009
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18. Focal plane wavefront sensing on SUBARU/SCExAO

Author

Schreiber, Laura, Schmidt, Dirk, Vernet, Elise, Vievard, S., Bos, S. P., Cassaing, F., Currie, T., Deo, V., Guyon, O., Jovanovic, N., Keller, C. U., Lamb, M., Lopez, C., Lozi, J., Martinache, F., Mary, D., Miller, K., Montmerle-Bonnefois, A., Mugnier, L. M., N'Diaye, M., Norris, B., Sahoo, A., Sauvage, J.-F., Skaf, N., Snik, F., Wilby, M. J., Wong, A., Schreiber, Laura, Schmidt, Dirk, Vernet, Elise, Vievard, S., Bos, S. P., Cassaing, F., Currie, T., Deo, V., Guyon, O., Jovanovic, N., Keller, C. U., Lamb, M., Lopez, C., Lozi, J., Martinache, F., Mary, D., Miller, K., Montmerle-Bonnefois, A., Mugnier, L. M., N'Diaye, M., Norris, B., Sahoo, A., Sauvage, J.-F., Skaf, N., Snik, F., Wilby, M. J., and Wong, A.

Abstract

Focal plane wavefront sensing is an elegant solution for wavefront sensing since near-focal images of any source taken by a detector show distortions in the presence of aberrations. Non-Common Path Aberrations and the Low Wind Effect both have the ability to limit the achievable contrast of the finest coronagraphs coupled with the best extreme adaptive optics systems. To correct for these aberrations, the Subaru Coronagraphic Extreme Adaptive Optics instrument hosts many focal plane wavefront sensors using detectors as close to the science detector as possible. We present seven of them and compare their implementation and efficiency on SCExAO. This work will be critical for wavefront sensing on next generation of extremely large telescopes that might present similar limitations.

Published
2020

19. Hunting Exoplanets with Single-Mode Optical Interferometry

Author

Abuter, R., Accardo, M., Adler, T., Amorim, A., Anugu, N., Ávila, G., Bauböck, M., Benisty, M., Berger, J.-P., Bestenlehner, J. M., Beust, H., Blind, N., Bonnefoy, M., BONNET, H., Bourget, P., Bouvier, J., Brandner, W., Brast, R., Buron, A., Burtscher, L., Cantalloube, F., Caratti O Garatti, A., Caselli, P., Cassaing, F., Chapron, F., Charnay, B., Choquet, E., Clénet, Y., Collin, C., Coudé Du Foresto, V., Davies, R., Deen, C., Delplancke-Ströbele, F., Dembet, R., Derie, F., de Wit, W.-J., Dexter, J., De Zeeuw, T., Dougados, C., Dubus, G., Duvert, G., Ebert, M., Eckart, A., Eisenhauer, F., Esselborn, M., Eupen, F., Fédou, P., Ferreira, M. C., Finger, G., Förster Schreiber, N. M., Gao, F., García Dabó, C. E., Garcia Lopez, R., Garcia, P. J. V., Gendron, É., Genzel, R., Gerhard, O., Gil, J. P., Gillessen, S., Gonté, F., Gordo, P., Gratadour, D., Greenbaum, A., Grellmann, R., Grözinger, U., Guajardo, P., Guieu, S., Habibi, M., Haguenauer, P., Hans, O., Haubois, X., Haug, M., Haußmann, F., Henning, T., Hippler, S., Hönig, S. F., Horrobin, M., Huber, A., Hubert, Z., Hubin, N., Hummel, C. A., Jakob, G., Janssen, A., Jimenez Rosales, A., Jochum, L., Jocou, L., Kammerer, J., Karl, M., Kaufer, A., Kellner, S., Kendrew, S., Kern, L., Kervella, P., Kiekebusch, M., Kishimoto, M., Klarmann, L., Klein, R., Köhler, R., Kok, Y., Kolb, J., Koutoulaki, M., Kulas, M., Labadie, L., Lacour, S., Lagrange, A.-M., Lapeyrère, V., Laun, W., Lazareff, B., Le Bouquin, J.-B., Léna, P., Lenzen, R., Lévêque, S., Lin, C.-C., Lippa, M., Lutz, D., Magnard, Y., Maire, A.-L., Mehrgan, L., Mérand, A., Millour, F., Mollière, P., Moulin, T., Müller, A., Müller, E., Müller, F., Netzer, H., Neumann, U., Nowak, M., Oberti, S., Ott, T., Pallanca, L., Panduro, J., Pasquini, L., Paumard, T., Percheron, I., Perraut, K., Perrin, G., Peterson, B. M., Petrucci, P.-O., Pflüger, A., Pfuhl, O., Phan Duc, T., Pineda, J. E., Plewa, P. m., Popovic, D., Pott, J.-U., Prieto, A., Pueyo, L., Rabien, S., Ramírez, A., Ramos, J. R., Rau, C., Ray, T., Riquelme, M., Rodríguez-Coira, G., Rohloff, R.-R., Rouan, D., Rousset, G., Sanchez-Bermudez, J., Schartmann, M., Scheithauer, S., Schöller, M., Schuhler, N., Segura-Cox, D., Shangguan, J., Shimizu, T. T., Spyromilio, J., Sternberg, A., Stock, M. R., Straub, O., Straubmeier, C., Sturm, E., Suárez Valles, M., Tacconi, L. J., Thi, W.-F., Tristram, K. R. W., Valenzuela, J. J., Van Boekel, R., Van Dishoeck, E. F., Vermot, P., Vincent, F., Von fellenberg, S., Waisberg, I., Wang, J. J., Wank, I., Weber, J., Weigelt, G., Widmann, F., Wieprecht, E., Wiest, M., Wiezorrek, E., Wittkowski, M., Woillez, J., Wolff, B., Yang, P., Yazici, S., Ziegler, D., Zins, G., and European Southern Observatory (ESO)

Subjects
[SDU]Sciences of the Universe [physics], Astrophysics::Instrumentation and Methods for Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract

The GRAVITY instrument was primarily conceived for imaging and astrometry of the Galactic centre. However, its sensitivity and astrometric capabilities have also enabled interferometry to reach a new domain of astrophysics: exoplanetology. In March 2019, the GRAVITY collaboration published the first spectrum and astrometry of an exoplanet obtained by optical interferometry. In this article, we show how this observation is paving the way to even more exciting discoveries — finding new planets, and characterising their atmospheres., Published in The Messenger vol. 178, pp. 47-49, December 2019.

Published
2019

20. Images at the Highest Angular Resolution with GRAVITY: The Case of η Carinae

Author

Abuter, R., Accardo, M., Adler, T., Amorim, A., Anugu, N., Ávila, G., Bauböck, M., Benisty, M., Berger, J.-P., Bestenlehner, J. M., Beust, H., Blind, N., Bonnefoy, M., BONNET, H., Bourget, P., Bouvier, J., Brandner, W., Brast, R., Buron, A., Burtscher, L., Cantalloube, F., Caratti O Garatti, A., Caselli, P., Cassaing, F., Chapron, F., Charnay, B., Choquet, E., Clénet, Y., Collin, C., Coudé Du Foresto, V., Davies, R., Deen, C., Delplancke-Ströbele, F., Dembet, R., Derie, F., de Wit, W.-J., Dexter, J., De Zeeuw, T., Dougados, C., Dubus, G., Duvert, G., Ebert, M., Eckart, A., Eisenhauer, F., Esselborn, M., Eupen, F., Fédou, P., Ferreira, M. C., Finger, G., Förster Schreiber, N. M., Gao, F., García Dabó, C. E., Garcia Lopez, R., Garcia, P. J. V., Gendron, É., Genzel, R., Gerhard, O., Gil, J. P., Gillessen, S., Gonté, F., Gordo, P., Gratadour, D., Greenbaum, A., Grellmann, R., Grözinger, U., Guajardo, P., Guieu, S., Habibi, M., Haguenauer, P., Hans, O., Haubois, X., Haug, M., Haußmann, F., Henning, T., Hippler, S., Hönig, S. F., Horrobin, M., Huber, A., Hubert, Z., Hubin, N., Hummel, C. A., Jakob, G., Janssen, A., Jimenez Rosales, A., Jochum, L., Jocou, L., Kammerer, J., Karl, M., Kaufer, A., Kellner, S., Kendrew, S., Kern, L., Kervella, P., Kiekebusch, M., Kishimoto, M., Klarmann, L., Klein, R., Köhler, R., Kok, Y., Kolb, J., Koutoulaki, M., Kulas, M., Labadie, L., Lacour, S., Lagrange, A.-M., Lapeyrère, V., Laun, W., Lazareff, B., Le Bouquin, J.-B., Léna, P., Lenzen, R., Lévêque, S., Lin, C.-C., Lippa, M., Lutz, D., Magnard, Y., Maire, A.-L., Mehrgan, L., Mérand, A., Millour, F., Mollière, P., Moulin, T., Müller, A., Müller, E., Müller, F., Netzer, H., Neumann, U., Nowak, M., Oberti, S., Ott, T., Pallanca, L., Panduro, J., Pasquini, L., Paumard, T., Percheron, I., Perraut, K., Perrin, G., Peterson, B. M., Petrucci, P.-O., Pflüger, A., Pfuhl, O., Phan Duc, T., Pineda, J. E., Plewa, P. m., Popovic, D., Pott, J.-U., Prieto, A., Pueyo, L., Rabien, S., Ramírez, A., Ramos, J. R., Rau, C., Ray, T., Riquelme, M., Rodríguez-Coira, G., Rohloff, R.-R., Rouan, D., Rousset, G., Sanchez-Bermudez, J., Schartmann, M., Scheithauer, S., Schöller, M., Schuhler, N., Segura-Cox, D., Shangguan, J., Shimizu, T. T., Spyromilio, J., Sternberg, A., Stock, M. R., Straub, O., Straubmeier, C., Sturm, E., Suárez Valles, M., Tacconi, L. J., Thi, W.-F., Tristram, K. R. W., Valenzuela, J. J., Van Boekel, R., Van Dishoeck, E. F., Vermot, P., Vincent, F., Von fellenberg, S., Waisberg, I., Wang, J. J., Wank, I., Weber, J., Weigelt, G., Widmann, F., Wieprecht, E., Wiest, M., Wiezorrek, E., Wittkowski, M., Woillez, J., Wolff, B., Yang, P., Yazici, S., Ziegler, D., Zins, G., and European Southern Observatory (ESO)

Subjects
[SDU]Sciences of the Universe [physics], Astrophysics::High Energy Astrophysical Phenomena, 0103 physical sciences, Astrophysics::Instrumentation and Methods for Astrophysics, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, 01 natural sciences
Abstract

The main goal of an interferometer is to probe the physics of astronomical objects at the highest possible angular resolution. The most intuitive way of doing this is by reconstructing images from the interferometric data. GRAVITY at the Very Large Telescope Interferometer (VLTI) has proven to be a fantastic instrument in this endeavour. In this article, we describe the reconstruction of the wind-wind collision cavity of the massive binary η Car with GRAVITY across two spectral lines: HeI and Brγ., Published in The Messenger vol. 178, pp. 31-33, December 2019.

Published
2019

21. Off-Axis Nulling Transfer Function Measurement: A First Assessment

Author

Vedova, G. Dalla, Menut, J.-L, Millour, F, Petrov, R, Cassaing, F, Danchi, W. C, Jacquinod, S, Lhome, E, Lopez, B, Lozi, J, Marcotto, A, Parisot, J, and Reess, J.-M

Subjects
Astrophysics
Abstract

We want to study a polychromatic inverse problem method with nulling interferometers to obtain information on the structures of the exozodiacal light. For this reason, during the first semester of 2013, thanks to the support of the consortium PERSEE, we launched a campaign of laboratory measurements with the nulling interferometric test bench PERSEE, operating with 9 spectral channels between J and K bands. Our objective is to characterise the transfer function, i.e. the map of the null as a function of wavelength for an off-axis source, the null being optimised on the central source or on the source photocenter. We were able to reach on-axis null depths better than 10(exp −4). This work is part of a broader project aiming at creating a simulator of a nulling interferometer in which typical noises of a real instrument are introduced. We present here our first results.

Published
2013

23. Spatially Resolving the Quasar Broad Emission Line Region

Author

Abuter, R., Accardo, M., Adler, T., Amorim, A., Anugu, N., Ávila, G., Bauböck, M., Benisty, M., Berger, J.-P., Bestenlehner, J.M., Beust, H., Blind, N., Bonnefoy, M., Bonnet, H., Bourget, P., Bouvier, J., Brandner, W., Brast, R., Buron, A., Burtscher, L.H., Cantalloube, F., Caratti, O, Garatti, A., Caselli, P., Cassaing, F., Chapron, F., Charnay, B., Choquet, É., Clénet, Y., Collin, C., Coudé Du, Foresto, V., Davies, R., Deen, C., Delplancke-Ströbele, F., Dembet, R., Derie, F., De Wit, W.-J., Dexter, J., Zeeuw, T. de, Dougados, C., Dubus, G., Duvert, G., Ebert, M., Eckart, A., Eisenhauer, F., Esselborn, M., Eupen, F., Fédou, P., Ferreira, M.C., Finger, G., Förster Schreiber, N.M., Gao, F., García Dabó, C.E., Garcia Lopez, R., Garcia, P.J.V., Gendron, É., Genzel, R., Gerhard, O., Gil, J.P., Gillessen, S., Gonté, F., Gordo, P., Gratadour, D., Greenbaum, A., Grellmann, R., Grözinger, U., Guajardo, P., Guieu, S., Habibi, M., Haguenauer, P., Hans, O., Haubois, X., Haug, M., Haußmann, F., Henning, T., Hippler, S., Hönig, S.F., Horrobin, M., Huber, A., Hubert, Z., Hubin, N., Hummel, C.~A., Jakob, G., Janssen, A., Jimenez Rosales, A., Jochum, L., Jocou, L., Kammerer, J., Karl, M., Kaufer, A., Kellner, S., Kendrew, S., Kern, L., Kervella, P., Kiekebusch, M., Kishimoto, M., Klarmann, L., Klein, R., Köhler, R., Kok, Y., Kolb, J., Koutoulaki, M., Kulas, M., Labadie, L., Lacour, S., Lagrange, A.-M., Lapeyrère, V., Laun, W., Lazareff, B., Le Bouquin, J.-B., Léna, P., Lenzen, R., Lévêque, S., Lin, C.-C., Lippa, M., Lutz, D., Magnard, Y., Maire, A.-L., Mehrgan, L., Mérand, A., Millour, F., Mollière, P., Moulin, T., Müller, A., Müller, E., Müller, F., Netzer, H., Neumann, U., Nowak, M., Oberti, S., Ott, T., Pallanca, L., Panduro, J., Pasquini, L., Paumard, T., Percheron, I., Perraut, K., Perrin, G., Peterson, B.M., Petrucci, P.-O., Pflüger, A., Pfuhl, O., Phan Duc, T., Pineda, J.E., Plewa, P.M., Popovic, D., Pott, J.-U., Prieto, A., Pueyo, L., Rabien, S., Ramírez, A., Ramos, J.R., Rau, C., Ray, T., Riquelme, M., Rodríguez-Coira, G., Rohloff, R.-R., Rouan, D., Rousset, G., Sanchez-Bermudez, J., Schartmann, M., Scheithauer, S., Schöller, M., Schuhler, N., Segura-Cox, D., Shangguan, J., Shimizu, T.T., Spyromilio, J., Sternberg, A., Stock, M.R., Straub, O., Straubmeier, C., Sturm, E., Suárez Valles, M., Tacconi, L.J., Thi, W.-F., Tristram, K.R.W., Valenzuela, J.J., Boekel, R. van, Dishoeck, E.F. van, Vermot, P., Vincent, F., Von Fellenberg, S., Waisberg, I., Wang, J.J., Wank, I., Weber, J., Weigelt, G., Widmann, F., Wieprecht, E., Wiest, M., Wiezorrek, E., Wittkowski, M., Woillez, J., Wolff, B., Yang, P., Yazici, S., Ziegler, D., Zins, G., 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
General Relativity and Quantum Cosmology, [SDU]Sciences of the Universe [physics], Astrophysics::High Energy Astrophysical Phenomena, 0103 physical sciences, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 010303 astronomy & astrophysics, 01 natural sciences, Astrophysics::Galaxy Astrophysics
Abstract

The angular resolution of the Very Large Telescope Interferometer (VLTI) and the excellent sensitivity of GRAVITY have led to the first detection of spatially resolved kinematics of high velocity atomic gas near an accreting super- massive black hole, revealing rotation on sub-parsec scales in the quasar 3C 273 at a distance of 550 Mpc. The observations can be explained as the result of circular orbits in a thick disc configuration around a 300 million solar mass black hole. Within an ongoing Large Programme, this capability will be used to study the kinematics of atomic gas and its relation to hot dust in a sample of quasars and Seyfert galaxies. We will measure a new radius-luminosity relation from spatially resolved data and test the current methods used to measure black hole mass in large surveys., Published in The Messenger vol. 178, pp. 20-24, December 2019.

Published
2019

24. Multiple Star Systems in the Orion Nebula

Author

Abuter, R., Accardo, M., Adler, T., Amorim, A., Anugu, N., Ávila, G., Bauböck, M., Benisty, M., Berger, J.-P., Bestenlehner, J. M., Beust, H., Blind, N., Bonnefoy, M., BONNET, H., Bourget, P., Bouvier, J., Brandner, W., Brast, R., Buron, A., Burtscher, L., Cantalloube, F., Caratti O Garatti, A., Caselli, P., Cassaing, F., Chapron, F., Charnay, B., Choquet, E., Clénet, Y., Collin, C., Coudé Du Foresto, V., Davies, R., Deen, C., Delplancke-Ströbele, F., Dembet, R., Derie, F., de Wit, W.-J., Dexter, J., De Zeeuw, T., Dougados, C., Dubus, G., Duvert, G., Ebert, M., Eckart, A., Eisenhauer, F., Esselborn, M., Eupen, F., Fédou, P., Ferreira, M. C., Finger, G., Förster Schreiber, N. M., Gao, F., García Dabó, C. E., Garcia Lopez, R., Garcia, P. J. V., Gendron, É., Genzel, R., Gerhard, O., Gil, J. P., Gillessen, S., Gonté, F., Gordo, P., Gratadour, D., Greenbaum, A., Grellmann, R., Grözinger, U., Guajardo, P., Guieu, S., Habibi, M., Haguenauer, P., Hans, O., Haubois, X., Haug, M., Haußmann, F., Henning, T., Hippler, S., Hönig, S. F., Horrobin, M., Huber, A., Hubert, Z., Hubin, N., Hummel, C. A., Jakob, G., Janssen, A., Jimenez Rosales, A., Jochum, L., Jocou, L., Kammerer, J., Karl, M., Kaufer, A., Kellner, S., Kendrew, S., Kern, L., Kervella, P., Kiekebusch, M., Kishimoto, M., Klarmann, L., Klein, R., Köhler, R., Kok, Y., Kolb, J., Koutoulaki, M., Kulas, M., Labadie, L., Lacour, S., Lagrange, A.-M., Lapeyrère, V., Laun, W., Lazareff, B., Le Bouquin, J.-B., Léna, P., Lenzen, R., Lévêque, S., Lin, C.-C., Lippa, M., Lutz, D., Magnard, Y., Maire, A.-L., Mehrgan, L., Mérand, A., Millour, F., Mollière, P., Moulin, T., Müller, A., Müller, E., Müller, F., Netzer, H., Neumann, U., Nowak, M., Oberti, S., Ott, T., Pallanca, L., Panduro, J., Pasquini, L., Paumard, T., Percheron, I., Perraut, K., Perrin, G., Peterson, B. M., Petrucci, P.-O., Pflüger, A., Pfuhl, O., Phan Duc, T., Pineda, J. E., Plewa, P. m., Popovic, D., Pott, J.-U., Prieto, A., Pueyo, L., Rabien, S., Ramírez, A., Ramos, J. R., Rau, C., Ray, T., Riquelme, M., Rodríguez-Coira, G., Rohloff, R.-R., Rouan, D., Rousset, G., Sanchez-Bermudez, J., Schartmann, M., Scheithauer, S., Schöller, M., Schuhler, N., Segura-Cox, D., Shangguan, J., Shimizu, T. T., Spyromilio, J., Sternberg, A., Stock, M. R., Straub, O., Straubmeier, C., Sturm, E., Suárez Valles, M., Tacconi, L. J., Thi, W.-F., Tristram, K. R. W., Valenzuela, J. J., Van Boekel, R., Van Dishoeck, E. F., Vermot, P., Vincent, F., Von fellenberg, S., Waisberg, I., Wang, J. J., Wank, I., Weber, J., Weigelt, G., Widmann, F., Wieprecht, E., Wiest, M., Wiezorrek, E., Wittkowski, M., Woillez, J., Wolff, B., Yang, P., Yazici, S., Ziegler, D., Zins, G., and European Southern Observatory (ESO)

Subjects
[SDU]Sciences of the Universe [physics], Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract

GRAVITY observations reveal that most massive stars in the Orion Trapezium cluster live in multiple systems. Our deep, milliarcsecond-resolution interferometry fills the gap at 1–100 astronomical units (au), which is not accessible to traditional imaging and spectroscopy, but is crucial to uncovering the mystery of high-mass star formation.The new observations find a significantly higher companion fraction than earlier studies of mostly OB associations. The observed distribution of mass ratios declines steeply with mass and follows a Salpeter power-law initial mass function. The observations therefore exclude stellar mergers as the dominant formation mechanism for massive stars in Orion., Published in The Messenger vol. 178, pp. 36-38, December 2019.

Published
2019
Full Text
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25. Spatially Resolving the Inner Gaseous Disc of the Herbig Star 51 Oph through its CO Ro-vibration Emission

Author

Abuter, R., Accardo, M., Adler, T., Amorim, A., Anugu, N., Ávila, G., Bauböck, M., Benisty, M., Berger, J.-P., Bestenlehner, J. M., Beust, H., Blind, N., Bonnefoy, M., BONNET, H., Bourget, P., Bouvier, J., Brandner, W., Brast, R., Buron, A., Burtscher, L., Cantalloube, F., Caratti O Garatti, A., Caselli, P., Cassaing, F., Chapron, F., Charnay, B., Choquet, E., Clénet, Y., Collin, C., Coudé Du Foresto, V., Davies, R., Deen, C., Delplancke-Ströbele, F., Dembet, R., Derie, F., de Wit, W.-J., Dexter, J., De Zeeuw, T., Dougados, C., Dubus, G., Duvert, G., Ebert, M., Eckart, A., Eisenhauer, F., Esselborn, M., Eupen, F., Fédou, P., Ferreira, M. C., Finger, G., Förster Schreiber, N. M., Gao, F., García Dabó, C. E., Garcia Lopez, R., Garcia, P. J. V., Gendron, É., Genzel, R., Gerhard, O., Gil, J. P., Gillessen, S., Gonté, F., Gordo, P., Gratadour, D., Greenbaum, A., Grellmann, R., Grözinger, U., Guajardo, P., Guieu, S., Habibi, M., Haguenauer, P., Hans, O., Haubois, X., Haug, M., Haußmann, F., Henning, T., Hippler, S., Hönig, S. F., Horrobin, M., Huber, A., Hubert, Z., Hubin, N., Hummel, C. A., Jakob, G., Janssen, A., Jimenez Rosales, A., Jochum, L., Jocou, L., Kammerer, J., Karl, M., Kaufer, A., Kellner, S., Kendrew, S., Kern, L., Kervella, P., Kiekebusch, M., Kishimoto, M., Klarmann, L., Klein, R., Köhler, R., Kok, Y., Kolb, J., Koutoulaki, M., Kulas, M., Labadie, L., Lacour, S., Lagrange, A.-M., Lapeyrère, V., Laun, W., Lazareff, B., Le Bouquin, J.-B., Léna, P., Lenzen, R., Lévêque, S., Lin, C.-C., Lippa, M., Lutz, D., Magnard, Y., Maire, A.-L., Mehrgan, L., Mérand, A., Millour, F., Mollière, P., Moulin, T., Müller, A., Müller, E., Müller, F., Netzer, H., Neumann, U., Nowak, M., Oberti, S., Ott, T., Pallanca, L., Panduro, J., Pasquini, L., Paumard, T., Percheron, I., Perraut, K., Perrin, G., Peterson, B. M., Petrucci, P.-O., Pflüger, A., Pfuhl, O., Phan Duc, T., Pineda, J. E., Plewa, P. m., Popovic, D., Pott, J.-U., Prieto, A., Pueyo, L., Rabien, S., Ramírez, A., Ramos, J. R., Rau, C., Ray, T., Riquelme, M., Rodríguez-Coira, G., Rohloff, R.-R., Rouan, D., Rousset, G., Sanchez-Bermudez, J., Schartmann, M., Scheithauer, S., Schöller, M., Schuhler, N., Segura-Cox, D., Shangguan, J., Shimizu, T. T., Spyromilio, J., Sternberg, A., Stock, M. R., Straub, O., Straubmeier, C., Sturm, E., Suárez Valles, M., Tacconi, L. J., Thi, W.-F., Tristram, K. R. W., Valenzuela, J. J., Van Boekel, R., Van Dishoeck, E. F., Vermot, P., Vincent, F., Von fellenberg, S., Waisberg, I., Wang, J. J., Wank, I., Weber, J., Weigelt, G., Widmann, F., Wieprecht, E., Wiest, M., Wiezorrek, E., Wittkowski, M., Woillez, J., Wolff, B., Yang, P., Yazici, S., Ziegler, D., Zins, G., and European Southern Observatory (ESO)

Subjects
[SDU]Sciences of the Universe [physics], Astrophysics::Instrumentation and Methods for Astrophysics, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract

Near-infrared interferometry gives us the opportunity to spatially resolve the circumstellar environment of young stars at sub-astronomical-unit (au) scales, which a standalone telescope could not reach. In particular, the sensitivity of GRAVITY on the VLTI allows us to spatially resolve the CO overtone emission at 2.3 microns. In this article, we present a new method of using the model of the CO spectrum to reconstruct the differential phase signal and extract the geometry and size of the emitting region., Published in The Messenger vol. 178, pp. 40-42, December 2019.

Published
2019
Full Text
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26. An Image of the Dust Sublimation Region in the Nucleus of NGC 1068

Author

Abuter, R., Accardo, M., Adler, T., Amorim, A., Anugu, N., Ávila, G., Bauböck, M., Benisty, M., Berger, J.-P., Bestenlehner, J. M., Beust, H., Blind, N., Bonnefoy, M., BONNET, H., Bourget, P., Bouvier, J., Brandner, W., Brast, R., Buron, A., Burtscher, L., Cantalloube, F., Caratti O Garatti, A., Caselli, P., Cassaing, F., Chapron, F., Charnay, B., Choquet, E., Clénet, Y., Collin, C., Coudé Du Foresto, V., Davies, R., Deen, C., Delplancke-Ströbele, F., Dembet, R., Derie, F., de Wit, W.-J., Dexter, J., De Zeeuw, T., Dougados, C., Dubus, G., Duvert, G., Ebert, M., Eckart, A., Eisenhauer, F., Esselborn, M., Eupen, F., Fédou, P., Ferreira, M. C., Finger, G., Förster Schreiber, N. M., Gao, F., García Dabó, C. E., Garcia Lopez, R., Garcia, P. J. V., Gendron, É., Genzel, R., Gerhard, O., Gil, J. P., Gillessen, S., Gonté, F., Gordo, P., Gratadour, D., Greenbaum, A., Grellmann, R., Grözinger, U., Guajardo, P., Guieu, S., Habibi, M., Haguenauer, P., Hans, O., Haubois, X., Haug, M., Haußmann, F., Henning, T., Hippler, S., Hönig, S. F., Horrobin, M., Huber, A., Hubert, Z., Hubin, N., Hummel, C. A., Jakob, G., Janssen, A., Jimenez Rosales, A., Jochum, L., Jocou, L., Kammerer, J., Karl, M., Kaufer, A., Kellner, S., Kendrew, S., Kern, L., Kervella, P., Kiekebusch, M., Kishimoto, M., Klarmann, L., Klein, R., Köhler, R., Kok, Y., Kolb, J., Koutoulaki, M., Kulas, M., Labadie, L., Lacour, S., Lagrange, A.-M., Lapeyrère, V., Laun, W., Lazareff, B., Le Bouquin, J.-B., Léna, P., Lenzen, R., Lévêque, S., Lin, C.-C., Lippa, M., Lutz, D., Magnard, Y., Maire, A.-L., Mehrgan, L., Mérand, A., Millour, F., Mollière, P., Moulin, T., Müller, A., Müller, E., Müller, F., Netzer, H., Neumann, U., Nowak, M., Oberti, S., Ott, T., Pallanca, L., Panduro, J., Pasquini, L., Paumard, T., Percheron, I., Perraut, K., Perrin, G., Peterson, B. M., Petrucci, P.-O., Pflüger, A., Pfuhl, O., Phan Duc, T., Pineda, J. E., Plewa, P. m., Popovic, D., Pott, J.-U., Prieto, A., Pueyo, L., Rabien, S., Ramírez, A., Ramos, J. R., Rau, C., Ray, T., Riquelme, M., Rodríguez-Coira, G., Rohloff, R.-R., Rouan, D., Rousset, G., Sanchez-Bermudez, J., Schartmann, M., Scheithauer, S., Schöller, M., Schuhler, N., Segura-Cox, D., Shangguan, J., Shimizu, T. T., Spyromilio, J., Sternberg, A., Stock, M. R., Straub, O., Straubmeier, C., Sturm, E., Suárez Valles, M., Tacconi, L. J., Thi, W.-F., Tristram, K. R. W., Valenzuela, J. J., Van Boekel, R., Van Dishoeck, E. F., Vermot, P., Vincent, F., Von fellenberg, S., Waisberg, I., Wang, J. J., Wank, I., Weber, J., Weigelt, G., Widmann, F., Wieprecht, E., Wiest, M., Wiezorrek, E., Wittkowski, M., Woillez, J., Wolff, B., Yang, P., Yazici, S., Ziegler, D., Zins, G., 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
[SDU]Sciences of the Universe [physics], Astrophysics::High Energy Astrophysical Phenomena, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 010303 astronomy & astrophysics, 01 natural sciences, Astrophysics::Galaxy Astrophysics
Abstract

The superb resolution of the Very Large Telescope Interferometer (VLTI) and the unrivalled sensitivity of GRAVITY have allowed us to reconstruct the first detailed image of the dust sublimation region in an active galaxy. In the nearby archetypal Seyfert 2 galaxy NGC 1068, the 2 µm continuum emission traces a highly inclined thin ring-like structure with a radius of 0.24 pc. The observed morphology challenges the picture of a geometrically and optically thick torus., Published in The Messenger vol. 178, pp. 24-26, December 2019.

Published
2019

27. Probing the Discs of Herbig Ae/Be Stars at Terrestrial Orbits

Author

Abuter, R., Accardo, M., Adler, T., Amorim, A., Anugu, N., Ávila, G., Bauböck, M., Benisty, M., Berger, J.-P., Bestenlehner, J. M., Beust, H., Blind, N., Bonnefoy, M., BONNET, H., Bourget, P., Bouvier, J., Brandner, W., Brast, R., Buron, A., Burtscher, L., Cantalloube, F., Caratti O Garatti, A., Caselli, P., Cassaing, F., Chapron, F., Charnay, B., Choquet, E., Clénet, Y., Collin, C., Coudé Du Foresto, V., Davies, R., Deen, C., Delplancke-Ströbele, F., Dembet, R., Derie, F., de Wit, W.-J., Dexter, J., De Zeeuw, T., Dougados, C., Dubus, G., Duvert, G., Ebert, M., Eckart, A., Eisenhauer, F., Esselborn, M., Eupen, F., Fédou, P., Ferreira, M. C., Finger, G., Förster Schreiber, N. M., Gao, F., García Dabó, C. E., Garcia Lopez, R., Garcia, P. J. V., Gendron, É., Genzel, R., Gerhard, O., Gil, J. P., Gillessen, S., Gonté, F., Gordo, P., Gratadour, D., Greenbaum, A., Grellmann, R., Grözinger, U., Guajardo, P., Guieu, S., Habibi, M., Haguenauer, P., Hans, O., Haubois, X., Haug, M., Haußmann, F., Henning, T., Hippler, S., Hönig, S. F., Horrobin, M., Huber, A., Hubert, Z., Hubin, N., Hummel, C. A., Jakob, G., Janssen, A., Jimenez Rosales, A., Jochum, L., Jocou, L., Kammerer, J., Karl, M., Kaufer, A., Kellner, S., Kendrew, S., Kern, L., Kervella, P., Kiekebusch, M., Kishimoto, M., Klarmann, L., Klein, R., Köhler, R., Kok, Y., Kolb, J., Koutoulaki, M., Kulas, M., Labadie, L., Lacour, S., Lagrange, A.-M., Lapeyrère, V., Laun, W., Lazareff, B., Le Bouquin, J.-B., Léna, P., Lenzen, R., Lévêque, S., Lin, C.-C., Lippa, M., Lutz, D., Magnard, Y., Maire, A.-L., Mehrgan, L., Mérand, A., Millour, F., Mollière, P., Moulin, T., Müller, A., Müller, E., Müller, F., Netzer, H., Neumann, U., Nowak, M., Oberti, S., Ott, T., Pallanca, L., Panduro, J., Pasquini, L., Paumard, T., Percheron, I., Perraut, K., Perrin, G., Peterson, B. M., Petrucci, P.-O., Pflüger, A., Pfuhl, O., Phan Duc, T., Pineda, J. E., Plewa, P. m., Popovic, D., Pott, J.-U., Prieto, A., Pueyo, L., Rabien, S., Ramírez, A., Ramos, J. R., Rau, C., Ray, T., Riquelme, M., Rodríguez-Coira, G., Rohloff, R.-R., Rouan, D., Rousset, G., Sanchez-Bermudez, J., Schartmann, M., Scheithauer, S., Schöller, M., Schuhler, N., Segura-Cox, D., Shangguan, J., Shimizu, T. T., Spyromilio, J., Sternberg, A., Stock, M. R., Straub, O., Straubmeier, C., Sturm, E., Suárez Valles, M., Tacconi, L. J., Thi, W.-F., Tristram, K. R. W., Valenzuela, J. J., Van Boekel, R., Van Dishoeck, E. F., Vermot, P., Vincent, F., Von fellenberg, S., Waisberg, I., Wang, J. J., Wank, I., Weber, J., Weigelt, G., Widmann, F., Wieprecht, E., Wiest, M., Wiezorrek, E., Wittkowski, M., Woillez, J., Wolff, B., Yang, P., Yazici, S., Ziegler, D., Zins, G., and European Southern Observatory (ESO)

Subjects
[SDU]Sciences of the Universe [physics], Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract

More than 4000 exoplanets are known to date in systems that differ greatly from our Solar System. In particular, inner exoplanets tend to follow orbits around their parent star that are much more compact than that of Earth. These systems are also extremely diverse, covering a range of intrinsic properties. Studying the main physi- cal processes at play in the innermost regions of the protoplanetary discs is crucial to understanding how these planets form and migrate so close to their host. With GRAVITY, we focused on the study of near-infrared emission of a sample of young intermediate- mass stars, the Herbig Ae/Be stars., Published in The Messenger vol. 178, pp. 38-40, December 2019.

Published
2019
Full Text
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28. GRAVITY chromatic imaging of η Car’s core: Milliarcsecond resolution imaging of the wind-wind collision zone (Brγ, He I)

Author

Sanchez-Bermudez, J., Weigelt, G., Bestenlehner, J.M., Kervella, P., Brandner, W., Henning, T., Mueller, A., Perrin, G., Pott, J.-U., Schoeller, M., van Boeke, R., Abuter, R., Accardo, M., Amorim, A., Anugu, N., Avila, G., Benisty, M., Berger, J.P., Blind, N., Bonnet, H., Bourget, P., Brast, R., Buron, A., Cantalloube, F., Garatti, A.C.O., Cassaing, F., Chapron, F., Choquet, E., Clenet, Y., Collin, C., du Foresto, V.C., de Wit, W., de Zeeuw, T., Deen, C., Delplancke-Stroebele, F., Dembet, R., Derie, F., Dexter, J., Duvert, G., Ebert, M., Eckart, A., Eisenhauer, F., Esselborn, M., Fedou, P., Garcia, P.J.V., Dabo, C.E.G., Lopez, R.G., Gao, F., Gendron, E., Genzel, R., Gillessen, S., Haubois, X., Haug, M., Haussmann, F., Hippler, S., Horrobin, M., Huber, A., Hubert, Z., Hubin, N., Hummel, C.A., Jakob, G., Jochum, L., Jocou, L., Karl, M., Kaufer, A., Kellner, S., Kendrew, S., Kern, L., Kiekebusch, M., Klein, R., Kolb, J., Kulas, M., Lacour, S., Lapeyrere, V., Lazareff, B., Le Bouquin, J.-B., Lena, P., Lenzen, R., Leveque, S., Lippa, M., Magnard, Y., Mehrgan, L., Mellein, M., Merand, A., Moreno-Ventas, J., Moulin, T., Mueller, E., Mueller, F., Neumann, U., Oberti, S., Ott, T., Pallanca, L., Panduro, J., Pasquini, L., Paumard, T., Percheron, I., Perraut, K., Petrucci, P.-O., Pflueger, A., Pfuhl, O., Duc, T.P., Plewa, P.M., Popovic, D., Rabien, S., Ramirez, A., Ramos, J., Rau, C., Riquelme, M., Rodriguez-Coira, G., Rohloff, R.-R., Rosales, A., Rousset, G., Scheithauer, S., Schuhler, N., Spyromilio, J., Straub, O., Straubmeier, C., Sturm, E., Suarez, M., Tristram, K.R.W., Ventura, N., Vincent, F., Waisberg, I., Wank, I., Widmann, F., Wieprecht, E., Wiest, M., Wiezorrek, E., Wittkowski, M., Woillez, J., Wolff, B., Yazici, S., Ziegler, D., Zins, G., and Collaboration, GRAVITY

Subjects
Astrophysics::Solar and Stellar Astrophysics
Abstract

Context. η Car is one of the most intriguing luminous blue variables in the Galaxy. Observations and models of the X-ray, ultraviolet, optical, and infrared emission suggest a central binary in a highly eccentric orbit with a 5.54 yr period residing in its core. 2D and 3D radiative transfer and hydrodynamic simulations predict a primary with a dense and slow stellar wind that interacts with the faster and lower density wind of the secondary. The wind-wind collision scenario suggests that the secondary’s wind penetrates the primary’s wind creating a low-density cavity in it, with dense walls where the two winds interact. However, the morphology of the cavity and its physical properties are not yet fully constrained.\ud \ud Aims. We aim to trace the inner ∼5–50 au structure of η Car’s wind-wind interaction, as seen through Brγ and, for the first time, through the He I 2s-2p line.\ud \ud Methods. We have used spectro-interferometric observations with the K-band beam-combiner GRAVITY at the VLTI. The analyses of the data include (i) parametrical model-fitting to the interferometric observables, (ii) a CMFGEN model of the source’s spectrum, and (iii) interferometric image reconstruction.\ud \ud Results. Our geometrical modeling of the continuum data allows us to estimate its FWHM angular size close to 2 mas and an elongation ratio ϵ = 1.06 ± 0.05 over a PA = 130° ± 20°. Our CMFGEN modeling of the spectrum helped us to confirm that the role of the secondary should be taken into account to properly reproduce the observed Brγ and He I lines. Chromatic images across the Brγ line reveal a southeast arc-like feature, possibly associated to the hot post-shocked winds flowing along the cavity wall. The images of the He I 2s-2p line served to constrain the 20 mas (∼50 au) structure of the line-emitting region. The observed morphology of He I suggests that the secondary is responsible for the ionized material that produces the line profile. Both the Brγ and the He I 2s-2p maps are consistent with previous hydrodynamical models of the colliding wind scenario. Future dedicated simulations together with an extensive interferometric campaign are necessary to refine our constraints on the wind and stellar parameters of the binary, which finally will help us predict the evolutionary path of η Car.

Published
2018

29. GRAVITY chromatic imaging of η Car's core. Milliarcsecond resolution imaging of the wind-wind collision zone (Brγ, He I)

Author

Collaboration, G., Sanchez-Bermudez, J., Weigelt, G., Bestenlehner, J., Kervella, P., Brandner, W., Henning, T., Müller, A., Perrin, G., Pott, J., Schöller, M., van Boekel, R., Abuter, R., Accardo, M., Amorim, A., Anugu, N., Ávila, G., Benisty, M., Berger, J., Blind, N., Bonnet, H., Bourget, P., Brast, R., Buron, A., Cantalloube, F., Caratti O Garatti, A., Cassaing, F., Chapron, F., Choquet, E., Clénet, Y., Collin, C., Coudé Du Foresto, V., de Wit, W., de Zeeuw, T., Deen, C., Delplancke-Ströbele, F., Dembet, R., Derie, F., Dexter, J., Duvert, G., Ebert, M., Eckart, A., Eisenhauer, F., Esselborn, M., Fédou, P., Garcia, P., Garcia Dabo, C., Garcia Lopez, R., Gao, F., Gendron, E., Genzel, R., Gillessen, S., Haubois, X., Haug, M., Haussmann, F., Hippler, S., Horrobin, M., Huber, A., Hubert, Z., Hubin, N., Hummel, C., Jakob, G., Jochum, L., Jocou, L., Karl, M., Kaufer, A., Kellner, S., Kendrew, S., Kern, L., Kiekebusch, M., Klein, R., Kolb, J., Kulas, M., Lacour, S., Lapeyrère, V., Lazareff, B., Le Bouquin, J., Léna, P., Lenzen, R., Lévêque, S., Lippa, M., Magnard, Y., Mehrgan, L., Mellein, M., Mérand, A., Moreno-Ventas, J., Moulin, T., Müller, E., Müller, F., Neumann, U., Oberti, S., Ott, T., Pallanca, L., Panduro, J., Pasquini, L., Paumard, T., Percheron, I., Perraut, K., Petrucci, P., Pflüger, A., Pfuhl, O., Duc, T., Plewa, P., Popovic, D., Rabien, S., Ramirez, A., Ramos, J., Rau, C., Riquelme, M., Rodríguez-Coira, G., Rohloff, R., Rosales, A., Rousset, G., Scheithauer, S., Schuhler, N., Spyromilio, J., Straub, O., Straubmeier, C., Sturm, E., Suarez, M., Tristram, K., Ventura, N., Vincent, F., Waisberg, I., Wank, I., Widmann, F., Wieprecht, E., Wiest, M., Wiezorrek, E., Wittkowski, M., Woillez, J., Wolff, B., Yazici, S., Ziegler, D., and Zins, G.

Subjects
Astrophysics::Solar and Stellar Astrophysics
Abstract

Context. η Car is one of the most intriguing luminous blue variables in the Galaxy. Observations and models of the X-ray, ultraviolet, optical, and infrared emission suggest a central binary in a highly eccentric orbit with a 5.54 yr period residing in its core. 2D and 3D radiative transfer and hydrodynamic simulations predict a primary with a dense and slow stellar wind that interacts with the faster and lower density wind of the secondary. The wind-wind collision scenario suggests that the secondary's wind penetrates the primary's wind creating a low-density cavity in it, with dense walls where the two winds interact. However, the morphology of the cavity and its physical properties are not yet fully constrained. Aims: We aim to trace the inner ̃5-50 au structure of η Car's wind-wind interaction, as seen through Brγ and, for the first time, through the He I 2s-2p line. Methods: We have used spectro-interferometric observations with the K-band beam-combiner GRAVITY at the VLTI. The analyses of the data include (i) parametrical model-fitting to the interferometric observables, (ii) a CMFGEN model of the source's spectrum, and (iii) interferometric image reconstruction. Results: Our geometrical modeling of the continuum data allows us to estimate its FWHM angular size close to 2 mas and an elongation ratio ∊ = 1.06 ± 0.05 over a PA = 130° ± 20°. Our CMFGEN modeling of the spectrum helped us to confirm that the role of the secondary should be taken into account to properly reproduce the observed Brγ and He I lines. Chromatic images across the Brγ line reveal a southeast arc-like feature, possibly associated to the hot post-shocked winds flowing along the cavity wall. The images of the He I 2s-2p line served to constrain the 20 mas (̃50 au) structure of the line-emitting region. The observed morphology of He I suggests that the secondary is responsible for the ionized material that produces the line profile. Both the Brγ and the He I 2s-2p maps are consistent with previous hydrodynamical models of the colliding wind scenario. Future dedicated simulations together with an extensive interferometric campaign are necessary to refine our constraints on the wind and stellar parameters of the binary, which finally will help us predict the evolutionary path of η Car.

Published
2018

31. The GRAVITY fringe tracker

Author

Lacour, S., primary, Dembet, R., additional, Abuter, R., additional, Fédou, P., additional, Perrin, G., additional, Choquet, É., additional, Pfuhl, O., additional, Eisenhauer, F., additional, Woillez, J., additional, Cassaing, F., additional, Wieprecht, E., additional, Ott, T., additional, Wiezorrek, E., additional, Tristram, K. R. W., additional, Wolff, B., additional, Ramírez, A., additional, Haubois, X., additional, Perraut, K., additional, Straubmeier, C., additional, Brandner, W., additional, and Amorim, A., additional

Published
2019
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32. GRAVITY chromatic imaging of eta Car's core Milliarcsecond resolution imaging of the wind-wind collision zone (Br gamma, He i)

Author

Sanchez-Bermudez, J., Weigelt, G., Bestenlehner, J. M., Kervella, P., Brandner, W., Henning, Th, Mueller, A., Perrin, G., Pott, J-U, Schoeller, M., van Boeke, R., Abuter, R., Accardo, M., Amorim, A., Anugu, N., Avila, G., Benisty, M., Berger, J. P., Blind, N., Bonnet, H., Bourget, P., Brast, R., Buron, A., Cantalloube, F., Garatti, A. Caratti O., Cassaing, F., Chapron, F., Choquet, E., Clenet, Y., Collin, C., du Foresto, V. Coude, de Wit, W., de Zeeuw, T., Deen, C., Delplancke-Stroebele, F., Dembet, R., Derie, F., Dexter, J., Duvert, G., Ebert, M., Eckart, A., Eisenhauer, F., Esselborn, M., Fedou, P., Garcia, P. J., V, Dabo, C. E. Garcia, Lopez, R. Garcia, Gao, F., Gendron, E., Genzel, R., Gillessen, S., Haubois, X., Haug, M., Haussmann, F., Hippler, S., Horrobin, M., Huber, A., Hubert, Z., Hubin, N., Hummel, C. A., Jakob, G., Jochum, L., Jocou, L., Karl, M., Kaufer, A., Kellner, S., Kendrew, S., Kern, L., Kiekebusch, M., Klein, R., Kolb, J., Kulas, M., Lacour, S., Lapeyrere, V, Lazareff, B., Le Bouquin, J-B, Lena, P., Lenzen, R., Leveque, S., Lippa, M., Magnard, Y., Mehrgan, L., Mellein, M., Merand, A., Moreno-Ventas, J., Moulin, T., Mueller, E., Mueller, F., Neumann, U., Oberti, S., Ott, T., Pallanca, L., Panduro, J., Pasquini, L., Paumard, T., Percheron, I, Perraut, K., Petrucci, P-O, Pflueger, A., Pfuhl, O., Duc, T. P., Plewa, P. M., Popovic, D., Rabien, S., Ramirez, A., Ramos, J., Rau, C., Riquelme, M., Rodriguez-Coira, G., Rohloff, R-R, Rosales, A., Rousset, G., Scheithauer, S., Schuhler, N., Spyromilio, J., Straub, O., Straubmeier, C., Sturm, E., Suarez, M., Tristram, K. R. W., Ventura, N., Vincent, F., Waisberg, I, Wank, I, Widmann, F., Wieprecht, E., Wiest, M., Wiezorrek, E., Wittkowski, M., Woillez, J., Wolff, B., Yazici, S., Ziegler, D., Zins, G., Sanchez-Bermudez, J., Weigelt, G., Bestenlehner, J. M., Kervella, P., Brandner, W., Henning, Th, Mueller, A., Perrin, G., Pott, J-U, Schoeller, M., van Boeke, R., Abuter, R., Accardo, M., Amorim, A., Anugu, N., Avila, G., Benisty, M., Berger, J. P., Blind, N., Bonnet, H., Bourget, P., Brast, R., Buron, A., Cantalloube, F., Garatti, A. Caratti O., Cassaing, F., Chapron, F., Choquet, E., Clenet, Y., Collin, C., du Foresto, V. Coude, de Wit, W., de Zeeuw, T., Deen, C., Delplancke-Stroebele, F., Dembet, R., Derie, F., Dexter, J., Duvert, G., Ebert, M., Eckart, A., Eisenhauer, F., Esselborn, M., Fedou, P., Garcia, P. J., V, Dabo, C. E. Garcia, Lopez, R. Garcia, Gao, F., Gendron, E., Genzel, R., Gillessen, S., Haubois, X., Haug, M., Haussmann, F., Hippler, S., Horrobin, M., Huber, A., Hubert, Z., Hubin, N., Hummel, C. A., Jakob, G., Jochum, L., Jocou, L., Karl, M., Kaufer, A., Kellner, S., Kendrew, S., Kern, L., Kiekebusch, M., Klein, R., Kolb, J., Kulas, M., Lacour, S., Lapeyrere, V, Lazareff, B., Le Bouquin, J-B, Lena, P., Lenzen, R., Leveque, S., Lippa, M., Magnard, Y., Mehrgan, L., Mellein, M., Merand, A., Moreno-Ventas, J., Moulin, T., Mueller, E., Mueller, F., Neumann, U., Oberti, S., Ott, T., Pallanca, L., Panduro, J., Pasquini, L., Paumard, T., Percheron, I, Perraut, K., Petrucci, P-O, Pflueger, A., Pfuhl, O., Duc, T. P., Plewa, P. M., Popovic, D., Rabien, S., Ramirez, A., Ramos, J., Rau, C., Riquelme, M., Rodriguez-Coira, G., Rohloff, R-R, Rosales, A., Rousset, G., Scheithauer, S., Schuhler, N., Spyromilio, J., Straub, O., Straubmeier, C., Sturm, E., Suarez, M., Tristram, K. R. W., Ventura, N., Vincent, F., Waisberg, I, Wank, I, Widmann, F., Wieprecht, E., Wiest, M., Wiezorrek, E., Wittkowski, M., Woillez, J., Wolff, B., Yazici, S., Ziegler, D., and Zins, G.

Abstract

Context. eta Car is one of the most intriguing luminous blue variables in the Galaxy. Observations and models of the X-ray, ultraviolet, optical, and infrared emission suggest a central binary in a highly eccentric orbit with a 5.54 yr period residing in its core. 2D and 3D radiative transfer and hydrodynamic simulations predict a primary with a dense and slow stellar wind that interacts with the faster and lower density wind of the secondary. The wind-wind collision scenario suggests that the secondary's wind penetrates the primary's wind creating a low-density cavity in it, with dense walls where the two winds interact. However, the morphology of the cavity and its physical properties are not yet fully constrained. Aims. We aim to trace the inner similar to 5-50 au structure of eta Car's wind-wind interaction, as seen through Br gamma and, for the first time, through the He i 2s-2p line. Methods. We have used spectro-interferometric observations with the K-band beam-combiner GRAVITY at the VLTI. The analyses of the data include (i) parametrical model-fitting to the interferometric observables, (ii) a CMFGEN model of the source's spectrum, and (iii) interferometric image reconstruction. Results. Our geometrical modeling of the continuum data allows us to estimate its FWHM angular size close to 2 mas and an elongation ratio epsilon = 1.06 +/- 0.05 over a PA = 130 degrees +/- 20 degrees. Our CMFGEN modeling of the spectrum helped us to confirm that the role of the secondary should be taken into account to properly reproduce the observed Br gamma and He i lines. Chromatic images across the Br gamma line reveal a southeast arc-like feature, possibly associated to the hot post-shocked winds flowing along the cavity wall. The images of the He i 2s-2p line served to constrain the 20 mas (similar to 50 au) structure of the line-emitting region. The observed morphology of He i suggests that the secondary is responsible for the ionized material that produces the line profile

Published
2018

34. Multiple-aperture optical telescopes: cophasing sensor testbed

Author

Sorrente, B., primary, Cassaing, F., primary, Baron, F., primary, Coudrain, C., primary, Fleury, B., primary, Mendez, F., primary, Mugnier, L., primary, Bentadj-Paris, V., primary, Michau, V., primary, Montri, J., primary, Rousset, G., primary, Rousset-Rouviere, L., primary, and Velluet, M.-T., primary

Published
2018
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35. First light for GRAVITY: Phase referencing optical interferometry for the Very Large Telescope Interferometer

Author

Abuter, R., Accardo, M., Amorim, A., Anugu, N., Avila, G., Azouaoui, N., Benisty, M., Berger, J. P., Blind, N., Bonnet, H., Bourget, P., Brandner, W., Brast, R., Buron, A., Burtscher, L., Cassaing, F., Chapron, F., Choquet, E., Clenet, Y., Collin, C., du Foresto, V. Coude, de Wit, W., de Zeeuw, P. T., Deen, C., Delplancke-Stroebele, F., Dembet, R., Derie, F., Dexter, J., Duvert, G., Ebert, M., Eckart, A., Eisenhauer, F., Esselborn, M., Fedou, P., Finger, G., Garcia, P., Dabo, C. E. Garcia, Lopez, R. Garcia, Gendron, E., Genzel, R., Gillessen, S., Gonte, F., Gordo, P., Grould, M., Groezinger, U., Guieu, S., Haguenauer, P., Hans, O., Haubois, X., Haug, M., Haussmann, F., Henning, Th., Hippler, S., Horrobin, M., Huber, A., Hubert, Z., Hubin, N., Hummel, C. A., Jakob, G., Janssen, A., Jochum, L., Jocou, L., Kaufer, A., Kellner, S., Kendrew, S., Kern, L., Kervella, P., Kiekebusch, M., Klein, R., Kok, Y., Kolb, J., Kulas, M., Lacour, S., Lapeyrere, V., Lazareff, B., Le Bouquin, J. -B., Lena, P., Lenzen, R., Leveque, S., Lippa, M., Magnard, Y., Mehrgan, L., Mellein, M., Merand, A., Moreno-Ventas, J., Moulin, T., Mueller, E., Mueller, F., Neumann, U., Oberti, S., Ott, T., Pallanca, L., Panduro, J., Pasquini, L., Paumard, T., Percheron, I., Perraut, K., Perrin, G., Pflueger, A., Pfuhl, O., Duc, T. Phan, Plewa, P. M., Popovic, D., Rabien, S., Ramirez, A., Ramos, J., Rau, C., Riquelme, M., Rohloff, R. -R., Rousset, G., Sanchez-Bermudez, J., Scheithauer, S., Schoeller, M., Schuhler, N., Spyromilio, J., Straubmeier, C., Sturm, E., Suarez, M., Tristram, K. R. W., Ventura, N., Vincent, F., Waisberg, I., Wank, I., Weber, J., Wieprecht, E., Wiest, M., Wiezorrek, E., Wittkowski, M., Woillez, J., Wolff, B., Yazici, S., Ziegler, D., Zins, G., Abuter, R., Accardo, M., Amorim, A., Anugu, N., Avila, G., Azouaoui, N., Benisty, M., Berger, J. P., Blind, N., Bonnet, H., Bourget, P., Brandner, W., Brast, R., Buron, A., Burtscher, L., Cassaing, F., Chapron, F., Choquet, E., Clenet, Y., Collin, C., du Foresto, V. Coude, de Wit, W., de Zeeuw, P. T., Deen, C., Delplancke-Stroebele, F., Dembet, R., Derie, F., Dexter, J., Duvert, G., Ebert, M., Eckart, A., Eisenhauer, F., Esselborn, M., Fedou, P., Finger, G., Garcia, P., Dabo, C. E. Garcia, Lopez, R. Garcia, Gendron, E., Genzel, R., Gillessen, S., Gonte, F., Gordo, P., Grould, M., Groezinger, U., Guieu, S., Haguenauer, P., Hans, O., Haubois, X., Haug, M., Haussmann, F., Henning, Th., Hippler, S., Horrobin, M., Huber, A., Hubert, Z., Hubin, N., Hummel, C. A., Jakob, G., Janssen, A., Jochum, L., Jocou, L., Kaufer, A., Kellner, S., Kendrew, S., Kern, L., Kervella, P., Kiekebusch, M., Klein, R., Kok, Y., Kolb, J., Kulas, M., Lacour, S., Lapeyrere, V., Lazareff, B., Le Bouquin, J. -B., Lena, P., Lenzen, R., Leveque, S., Lippa, M., Magnard, Y., Mehrgan, L., Mellein, M., Merand, A., Moreno-Ventas, J., Moulin, T., Mueller, E., Mueller, F., Neumann, U., Oberti, S., Ott, T., Pallanca, L., Panduro, J., Pasquini, L., Paumard, T., Percheron, I., Perraut, K., Perrin, G., Pflueger, A., Pfuhl, O., Duc, T. Phan, Plewa, P. M., Popovic, D., Rabien, S., Ramirez, A., Ramos, J., Rau, C., Riquelme, M., Rohloff, R. -R., Rousset, G., Sanchez-Bermudez, J., Scheithauer, S., Schoeller, M., Schuhler, N., Spyromilio, J., Straubmeier, C., Sturm, E., Suarez, M., Tristram, K. R. W., Ventura, N., Vincent, F., Waisberg, I., Wank, I., Weber, J., Wieprecht, E., Wiest, M., Wiezorrek, E., Wittkowski, M., Woillez, J., Wolff, B., Yazici, S., Ziegler, D., and Zins, G.

Abstract

GRAVITY is a new instrument to coherently combine the light of the European Southern Observatory Very Large Telescope Interferometer to form a telescope with an equivalent 130m diameter angular resolution and a collecting area of 200 m(2). The instrument comprises fiber fed integrated optics beam combination, high resolution spectroscopy, built-in beam analysis and control, near-infrared wavefront sensing, phase-tracking, dual-beam operation, and laser metrology. GRAVITY opens up to optical/infrared interferometry the techniques of phase referenced imaging and narrow angle astrometry, in many aspects following the concepts of radio interferometry. This article gives an overview of GRAVITY and reports on the performance and the first astronomical observations during commissioning in 2015/16. We demonstrate phase-tracking on stars as faint as m(K) approximate to 10 mag, phase-referenced interferometry of objects fainter than m(K) approximate to 15 mag with a limiting magnitude of m(K) approximate to 17 mag, minute long coherent integrations, a visibility accuracy of better than 0.25%, and spectro-differential phase and closure phase accuracy better than 0.5 degrees, corresponding to a differential astrometric precision of better than ten microarcseconds (as). The dual-beam astrometry, measuring the phase difference of two objects with laser metrology, is still under commissioning. First observations show residuals as low as 50 mu as when following objects over several months. We illustrate the instrument performance with the observations of archetypical objects for the different instrument modes. Examples include the Galactic center supermassive black hole and its fast orbiting star S2 for phase referenced dual-beam observations and infrared wavefront sensing, the high mass X-ray binary BP Cru and the active galactic nucleus of PDS 456 for a few mu as spectro-differential astrometry, the T Tauri star S CrA for a spectro-differential visibility analysis, xi Tel and 24

Published
2017

36. Progress of the CHARA/SPICA project

Author

Tuthill, Peter G., Mérand, Antoine, Sallum, Stephanie, Pannetier, C., Mourard, D., Berio, P., Cassaing, F., Allouche, F., Anugu, N., Bailet, C., ten Brummelaar, T., Dejonghe, J., Gies, D., Jocou, L., Kraus, S., Lacour, S., Lagarde, S., Le Bouquin, J. B., Lecron, D., Monnier, J., Nardetto, N., Patru, F., Perraut, K., Petrov, R., Rousseau, S., Stee, P., Sturmann, J., and Sturmann, L.

Published
2020
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38. Towards a laboratory breadboard for PEGASE, the DARWIN pathfinder

Author

Cassaing, F., primary, Le Duigou, J.-M., additional, Sorrente, B., additional, Fleury, B., additional, Gorius, N., additional, Brachet, F., additional, Buisset, C., additional, Ollivier, M., additional, Hénault, F., additional, Mourard, D., additional, Rabbia, Y., additional, Delpech, M., additional, Guidotti, P.-Y., additional, Léger, A., additional, Barillot, M., additional, Rouan, D., additional, and Rousset, G., additional

Published
2017
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39. PEGASE: a free flying interferometer for the spectroscopy of giant exo-planets

Author

Le Duigou, J.-M., primary, Ollivier, M., additional, Léger, A., additional, Cassaing, F., additional, Sorrente, B., additional, Fleury, B., additional, Rousset, G., additional, Absil, O., additional, Mourard, D., additional, Rabbia, Y., additional, Escarrat, L., additional, Malbet, F., additional, Rouan, Daniel, additional, Clédassou, R., additional, Delpech, M., additional, Duchon, P., additional, Meyssignac, B., additional, Guidotti, P.-Y., additional, and Gorius, N., additional

Published
2017
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41. First results of the PERSEE experiment

Author

Le Duigou, J.-M., primary, Lozi, J., primary, Houairi, K., primary, Lhomé, E., primary, Marcotto, A., primary, Girard, P., primary, Coudé du Foresto, V., primary, Ollivier, M., primary, Cassaing, F., primary, Sorrente, B., primary, Montri, J., primary, Jacquinod, S., primary, Reess, J.-M., primary, Pham, L., primary, Buey, T., primary, Hénault, F., primary, Mauclert, N., primary, and Barillot, M., primary

Published
2017
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47. FIRST RESULTS OF THE PERSEE EXPERIMENT.

Author

Le Duigou, J. M., Lozi, J., Cassaing, F., Houairi, K., Sorrente, B., Montri, J., Jacquinod, S., Reess, J-M., Pham, L., Lhomé, E., Buey, T., Hénault, F., Marcotto, A., Girard, P., Mauclert, N., Barillot, M., du Foresto, V. Coudé, and Ollivier, M.

Published
2017
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49. An asymmetry detected in the disk of Kappa CMa with the AMBER/VLTI

Author

Meilland, Anthony, Millour, Florentin, Stee, Philippe, Domiciano De Souza, Armando, Petrov, Romain, Mourard, Denis, Jankov, Slobodan, Robbe-Dubois, Sylvie, Spang, Alain, Arisitidi, Eric, Antonelli, P., Beckmann, U., Bresson, Y., Chelli, A., Dugué, M., Duvert, G., Glück, L., Kern, P., Lagarde, S., Le Coarer, E., Lisi, F., Malbet, F., Perraut, K., Puget, P., Robbe-Dubois, S., Weigelt, G., Zins, G., Accardo, M., Acke, B., Agabi, K., Arezki, B., Altariba, E., Baffa, C., Behrend, J., Blöcker, T., Bonhomme, S., Busoni, S., Cassaing, F., Clausse, J.-M., Connot, C., Delboulbé, A., Domicinano De Souza, A., Driebe, T., Feautrier, P., Ferruzzi, D., Forveille, T., Fossat, E., Foy, R., Fraix-Burnet, D., Gallardo, A., Gennari, S., Glentzlin, A., Giani, E., Gilinst, C., Heiden, M., Heininger, M., Hernandez, O., Hofmann, K.-H., Kamm, D., Kraus, S., Le Contel, D., Le Contel, J.-M., Lopez, B., Magnard, Y., Marconi, A., Mars, G., Martinot-Lagarde, G., Mathias, P., Millour, F., Monin, J.-L., Mouillet, D., Mourard, D., Mège, P., Nussbaum, E., Ohnaka, K., Pacini, F., Perrier, C., Rabbia, Y., Rebattu, S., Reynaud, F., Richichi, A., Roussel, A., Sacchettini, M., Salinari, P., Schertl, D., Solscheid, W., Stee, P., Stefanini, P., Tallon, M., Tallon-Bosc, I., Tasso, D., Tatulli, E., Testi, L., Valtier, J.-C., Vannier, M., Ventura, N., Kiekebusch, M., Schöller, M., 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), 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), 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), and 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)

Subjects
[SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Stars: emission-line, Astrophysics (astro-ph), Stars: individual (kappa CMa), FOS: Physical sciences, Be, Astrophysics, Techniques: high angular resolution, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Stars: Keplerian rotation, Techniques: interferometric, Stars: circumstellar matter, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract

International audience; 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

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

Author

Malbet, F., Benisty, M., de Wit, W.J., Kraus, S., Meilland, A., Millour, F., Tatulli, E., Berger, J.P., Chesneau, O., Hofmann, K.H., Isella, A., Natta, A., Petrov, R., Preibisch, T., Stee, P., Testi, L., Weigelt, G., Antonelli, P., Beckmann, U., Bresson, Y., Chelli, A., Duvert, G., Glück, L., Kern, P., Lagarde, S., Le Coarer, E., Lisi, F., Perraut, K., Robbe-Dubois, S., Roussel, A., Zins, G., Accardo, M., Acke, B., Agabi, K., Arezki, B., Aristidi, E., Baffa, C., Behrend, J., Blöcker, T., Bonhomme, S., Busoni, S., Cassaing, F., Clausse, J.-M., Colin, J., Connot, C., Delboulbé, A., Driebe, T., Dugué, M., Feautrier, P., Ferruzzi, D., Forveille, T., Fossat, E., Foy, Renaud, Fraix-Burnet, D., Gallardo, A., Gennari, S., Glentzlin, A., Giani, E., Gil, C., Heiden, M., Heininger, M., Kamm, D., Le Contel, D., Le Contel, J.-M., Lopez, B., Magnard, Y., Marconi, A., Mars, G., Martinot-Lagarde, G., Mathias, P., Monin, J.-L., Mouillet, D., Mourard, D., Mège, P., Nussbaum, E., Ohnaka, K., Pacheco, J., Pacini, F., Perrier, C., Puget, P., Rabbia, Y., Rebattu, S., Reynaud, François, Richichi, A., Sacchettini, M., Salinari, P., Schertl, D., Solscheid, W., Stefanini, P., Tallon, Michel, Tallon-Bosc, Isabelle, Tasso, D., Valtier, J.-C., Vannier, M., Ventura, N., Kiekebusch, M., Rantakyrö, F., Schöller, M., 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), Max-Planck-Institut für Radioastronomie (MPIFR), 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), 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), INAF - Osservatorio Astrofisico di Arcetri (OAA), Istituto Nazionale di Astrofisica (INAF), ONERA - The French Aerospace Lab [Châtillon], ONERA, 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), Division technique INSU/SDU (DTI), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), 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), European Southern Observatory (ESO), AMBER, 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)-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), 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), Université Nice Sophia Antipolis (1965 - 2019) (UNS), 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
Protoplanetary disks, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Astrophysics::High Energy Astrophysical Phenomena, Astrophysics (astro-ph), FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Pre-main-sequence stars, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Planetary systems, Early-type stars, Emission-line stars, Accretion disks, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Infrared, Interferometric Techniques, Astrophysics::Galaxy Astrophysics
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], Comment: 13 pages; to be published in A&A; Acceptance day: 11/10/2005

Published
2005
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