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19 results on '"Domiciano De Souza, Armando"'

2. ANDES, the high resolution spectrograph for the ELT:science goals, project overview, and future developments

Author

Vernet, Joël R., Bryant, Julia J., Motohara, Kentaro, Marconi, Alessandro, Abreu, Artur R., Adibekyan, Vardan, Alberti, Valentina, Albrecht, Simon, Alcaniz, Jailson, Aliverti, Matteo, Allende Prieto, Carlos, Alvarado-gomez, Julian, Alves, Catarina, Amado, Pedro J., Amate, Manuel, Andersen, Michael, Antoniucci, Simone, Artigau, E., Bailet, Christophe, Baker, Clark E., Baldini, Veronica, Balestra, Andrea, Barnes, S.a., Baron, Frédérique, Barros, Susana, Bauer, Svend-marian, Beaulieu, Mathilde, Bellido-tirado, Olga, Benneke, Björn, Bensby, Thomas, Bergin, Edwin, Berio, P., Biazzo, Katia, Bigot, Laurent, Bik, Arjan, Birkby, Jayne L., Blind, Nicolas, Boebion, Olivier, Boisse, Isabelle, Bolmont, Emeline, Bolton, J. S., Bonaglia, Marco, Bonfils, Xavier, Bonhomme, Lea, Borsa, Francesco, Bouret, Jean-claude, Brandeker, Alexis, Brandner, Wolfgang, Broeg, Christopher H., Brogi, Matteo, Brousseau, Denis, Brucalassi, Anna, Brynnel, Joar G., Buchhave, Lars A., Buscher, David F., Cabona, Lorenzo, Cabral, Alexandre, Calderone, Giorgio, Calvo-ortega, Rocío, Cantalloube, Faustine, Canto Martins, Bruno L., Carbonaro, Luca, Caujolle, Yan, Chauvin, Gaël, Chazelas, Bruno, Cheffot, Anne-laure L., Cheng, Yuk Shan, Chiavassa, Andrea, Christensen, Lise B., Cirami, Roberto, Cirasuolo, Michele, Cook, Neil J., Cooke, Ryan, Coretti, Igor, Covino, Stefano, Cowan, Nicolas B., Cresci, Giovanni, Cristiani, Stefano, Parro, Vanderlei Cunha, Cupani, Guido, D'odorico, Valentina, Dadi, Kamalesh, De Castro Leão, Izan C., De Cia, Annalisa, De Medeiros, Jose R., Debras, Florian, Debus, Michael, Delorme, Alain, Demangeon, Olivier, Derie, Frederic, Dessauges-zavadsky, M., Di Marcantonio, Paolo, Di Stefano, Simona, Dionies, Frank, Domiciano De Souza, Armando, Doyon, René, Dunn, Jennifer S., Egner, Sébastien E., Ehrenreich, David, Faria, Joao P., Ferruzzi, Debora, Feruglio, Chiara, Fisher, Martin, Fontana, Adriano, Frank, B S., Fuesslein, C., Fumagalli, M., Fusco, Thierry, Fynbo, Johan P. U., Gabella, O., Gaessler, W., Gallo, E., Gao, X., Genolet, L., Genoni, M., Giacobbe, P., Giro, E., Gonçalves, R. S., Gonzalez, O. A., González-hernández, J. I., Gouvret, C., Gracia Témich, F., Haehnelt, M. G., Haniff, C., Hatzes, A., Helled, R., Hoeijmakers, H. J., Hughes, I., Huke, Philipp, Ivanisenko, Y., Järvinen, A. S., Järvinen, S. P., Kaminski, A., Kern, J., Knoche, J., Kordt, A., Korhonen, H., Korn, A., Kouach, D., Kowzan, G., Kreidberg, L., Landoni, M., Lanotte, A. A., Lavail, A., Lavie, B., Lee, D., Lehmitz, M., Li, J., Li, W., Liske, J., Lovis, C., Lucatello, S., Lunney, D., Macintosh, M. J., Madhusudhan, N., Magrini, L., Maiolino, R., Maldonado, J., Malo, L., Man, A. W. S., Marquart, T., Marques, C. M. J., Marques, E. L., Martinez, P., Martins, A. M., Martins, C. J. A. P., Martins, J. H. C., Maslowski, P., Mason, C., Mason, E., Mccracken, R. A., Melo E Sousa, M. A. F., Mergo, P., Micela, G., Milaković, D., Mollière, P., Monteiro, M. A., Montgomery, D., Mordasini, C., Morin, J., Mucciarelli, A., Murphy, M. T., N'diaye, M., Nardetto, N., Neichel, B., Neri, N., Niedzielski, A. T., Niemczura, E., Nisini, B., Nortmann, L., Noterdaeme, P., Nunes, N. J., Oggioni, L., Olchewsky, F., Oliva, E., Önel, H., Origlia, L., Östlin, G., Ouellette, N. N.-q., Pallé, Enric, Papaderos, P., Pariani, G., Pasquini, L., Peñate Castro, J., Pepe, F., Peroux, C., Perreault Levasseur, L., Perruchot, Sandrine, Petit, P., Pfuhl, Oliver, Pino, L., Piqueras, Javier, Piskunov, N., Pollo, A., Poppenhaeger, K., Porru, M., Puschnig, J., Quirrenbach, A., Rauscher, Emily, Rebolo, R., Redaelli, E. M. A., Reffert, S., Reid, D. T., Reiners, A., Richter, P., Riva, M., Rivoire, S., Rodríguez-lópez, C., Roederer, I. U., Romano, D., Roth, M., Rousseau, S., Rowe, J., Saccardi, A., Salvadori, S., Sanna, N., Santos, N. C., Santos Diaz, P., Sanz-forcada, Jorge, Sarajlic, M., Sauvage, J.-f., Savio, D., Scaudo, A., Schäfer, S., Schiavon, R. P., Schmidt, T. M., Selmi, C., Simoes, R., Simonnin, A., Sivanandam, S., Sordet, M., Sordo, R., Sortino, F., Sosnowska, D., Sousa, S. G., Spang, A., Spiga, R., Stempels, E., Stevenson, J. R. Y., Strassmeier, Klaus G., Suárez Mascareño, A., Sulich, A., Sun, X., Tanvir, N. R., Tenegi-sanginés, F., Thibault, S., Thompson, S. J., Tisserand, P., Tozzi, A., Turbet, M., Véran, J.-p., Vallée, P., Vanni, I., Varas, R., Vega-moreno, A., Venn, K. A., Verma, A., Vernet, J., Viel, M., Wade, G., Waring, C., Weber, M., Weder, J., Wehbé, B., Weingrill, J., Woche, M., Xompero, M., Zackrisson, E., Zanutta, A., Zapatero Osorio, M. R., Zechmeister, M., Zimara, J., Vernet, Joël R., Bryant, Julia J., Motohara, Kentaro, Marconi, Alessandro, Abreu, Artur R., Adibekyan, Vardan, Alberti, Valentina, Albrecht, Simon, Alcaniz, Jailson, Aliverti, Matteo, Allende Prieto, Carlos, Alvarado-gomez, Julian, Alves, Catarina, Amado, Pedro J., Amate, Manuel, Andersen, Michael, Antoniucci, Simone, Artigau, E., Bailet, Christophe, Baker, Clark E., Baldini, Veronica, Balestra, Andrea, Barnes, S.a., Baron, Frédérique, Barros, Susana, Bauer, Svend-marian, Beaulieu, Mathilde, Bellido-tirado, Olga, Benneke, Björn, Bensby, Thomas, Bergin, Edwin, Berio, P., Biazzo, Katia, Bigot, Laurent, Bik, Arjan, Birkby, Jayne L., Blind, Nicolas, Boebion, Olivier, Boisse, Isabelle, Bolmont, Emeline, Bolton, J. S., Bonaglia, Marco, Bonfils, Xavier, Bonhomme, Lea, Borsa, Francesco, Bouret, Jean-claude, Brandeker, Alexis, Brandner, Wolfgang, Broeg, Christopher H., Brogi, Matteo, Brousseau, Denis, Brucalassi, Anna, Brynnel, Joar G., Buchhave, Lars A., Buscher, David F., Cabona, Lorenzo, Cabral, Alexandre, Calderone, Giorgio, Calvo-ortega, Rocío, Cantalloube, Faustine, Canto Martins, Bruno L., Carbonaro, Luca, Caujolle, Yan, Chauvin, Gaël, Chazelas, Bruno, Cheffot, Anne-laure L., Cheng, Yuk Shan, Chiavassa, Andrea, Christensen, Lise B., Cirami, Roberto, Cirasuolo, Michele, Cook, Neil J., Cooke, Ryan, Coretti, Igor, Covino, Stefano, Cowan, Nicolas B., Cresci, Giovanni, Cristiani, Stefano, Parro, Vanderlei Cunha, Cupani, Guido, D'odorico, Valentina, Dadi, Kamalesh, De Castro Leão, Izan C., De Cia, Annalisa, De Medeiros, Jose R., Debras, Florian, Debus, Michael, Delorme, Alain, Demangeon, Olivier, Derie, Frederic, Dessauges-zavadsky, M., Di Marcantonio, Paolo, Di Stefano, Simona, Dionies, Frank, Domiciano De Souza, Armando, Doyon, René, Dunn, Jennifer S., Egner, Sébastien E., Ehrenreich, David, Faria, Joao P., Ferruzzi, Debora, Feruglio, Chiara, Fisher, Martin, Fontana, Adriano, Frank, B S., Fuesslein, C., Fumagalli, M., Fusco, Thierry, Fynbo, Johan P. U., Gabella, O., Gaessler, W., Gallo, E., Gao, X., Genolet, L., Genoni, M., Giacobbe, P., Giro, E., Gonçalves, R. S., Gonzalez, O. A., González-hernández, J. I., Gouvret, C., Gracia Témich, F., Haehnelt, M. G., Haniff, C., Hatzes, A., Helled, R., Hoeijmakers, H. J., Hughes, I., Huke, Philipp, Ivanisenko, Y., Järvinen, A. S., Järvinen, S. P., Kaminski, A., Kern, J., Knoche, J., Kordt, A., Korhonen, H., Korn, A., Kouach, D., Kowzan, G., Kreidberg, L., Landoni, M., Lanotte, A. A., Lavail, A., Lavie, B., Lee, D., Lehmitz, M., Li, J., Li, W., Liske, J., Lovis, C., Lucatello, S., Lunney, D., Macintosh, M. J., Madhusudhan, N., Magrini, L., Maiolino, R., Maldonado, J., Malo, L., Man, A. W. S., Marquart, T., Marques, C. M. J., Marques, E. L., Martinez, P., Martins, A. M., Martins, C. J. A. P., Martins, J. H. C., Maslowski, P., Mason, C., Mason, E., Mccracken, R. A., Melo E Sousa, M. A. F., Mergo, P., Micela, G., Milaković, D., Mollière, P., Monteiro, M. A., Montgomery, D., Mordasini, C., Morin, J., Mucciarelli, A., Murphy, M. T., N'diaye, M., Nardetto, N., Neichel, B., Neri, N., Niedzielski, A. T., Niemczura, E., Nisini, B., Nortmann, L., Noterdaeme, P., Nunes, N. J., Oggioni, L., Olchewsky, F., Oliva, E., Önel, H., Origlia, L., Östlin, G., Ouellette, N. N.-q., Pallé, Enric, Papaderos, P., Pariani, G., Pasquini, L., Peñate Castro, J., Pepe, F., Peroux, C., Perreault Levasseur, L., Perruchot, Sandrine, Petit, P., Pfuhl, Oliver, Pino, L., Piqueras, Javier, Piskunov, N., Pollo, A., Poppenhaeger, K., Porru, M., Puschnig, J., Quirrenbach, A., Rauscher, Emily, Rebolo, R., Redaelli, E. M. A., Reffert, S., Reid, D. T., Reiners, A., Richter, P., Riva, M., Rivoire, S., Rodríguez-lópez, C., Roederer, I. U., Romano, D., Roth, M., Rousseau, S., Rowe, J., Saccardi, A., Salvadori, S., Sanna, N., Santos, N. C., Santos Diaz, P., Sanz-forcada, Jorge, Sarajlic, M., Sauvage, J.-f., Savio, D., Scaudo, A., Schäfer, S., Schiavon, R. P., Schmidt, T. M., Selmi, C., Simoes, R., Simonnin, A., Sivanandam, S., Sordet, M., Sordo, R., Sortino, F., Sosnowska, D., Sousa, S. G., Spang, A., Spiga, R., Stempels, E., Stevenson, J. R. Y., Strassmeier, Klaus G., Suárez Mascareño, A., Sulich, A., Sun, X., Tanvir, N. R., Tenegi-sanginés, F., Thibault, S., Thompson, S. J., Tisserand, P., Tozzi, A., Turbet, M., Véran, J.-p., Vallée, P., Vanni, I., Varas, R., Vega-moreno, A., Venn, K. A., Verma, A., Vernet, J., Viel, M., Wade, G., Waring, C., Weber, M., Weder, J., Wehbé, B., Weingrill, J., Woche, M., Xompero, M., Zackrisson, E., Zanutta, A., Zapatero Osorio, M. R., Zechmeister, M., and Zimara, J.

Published
2024

4. The 10th VLTI School of Interferometry: Premiering a Fully Online Format

Author

Millour, Florentin, Meilland, Anthony, Matter, Alexis, Mella, Guillaume, Bourgès, Laurent, Paladini, Claudia, Tallon-Bosc, Isabelle, Tallon, Michel, Soulez, Ferreol, Buscher, David, Mérand, Antoine, Benisty, Myriam, van Boekel, Roy, Cruzalèbes, Pierre, Defrère, Denis, Domiciano de Souza, Armando, Filho, Mercedes, Garcia, Paulo, Hönig, Sebastian, Ligi, Roxanne, Maccotta, Camille, Mckean, John, Patru, Fabien, Perraut, Karine, Pott, Jörg-Uwe, Spang, Alain, Rousset, Sophie, Astronomy, Joseph Louis LAGRANGE (LAGRANGE), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, European Southern Observatory [Santiago] (ESO), European Southern Observatory (ESO), 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), Cavendish Laboratory, University of Cambridge [UK] (CAM), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, Max Planck Institute for Astronomy (MPIA), Institute of Astronomy [Leuven], Catholic University of Leuven - Katholieke Universiteit Leuven (KU Leuven), CENTRA and Universidade do Porto - Faculdade de Engenharia, 4200-465, Porto, Portugal, School of Physics and Astronomy [Southampton], University of Southampton, Kapteyn Astronomical Institute [Groningen], University of Groningen [Groningen], Netherlands Institute for Radio Astronomy (ASTRON), Chaire IPAG 'Entreprise Inclusive' (IPAG Business School), and IPAG Business School

Subjects
[PHYS.ASTR.IM]Physics [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract

Very Large Telescope Inerferometer (VLTI) schools have nearly a 20-year history and have trained a significant fraction of today���s optical interferometrists who use high-angular-resolution techniques on a regular basis. Very early in the development of the VLTI, training was identified by the community as a necessary tool, as the expertise in optical long-baseline interferometry was limited to a few groups in France and Germany (in those early years the UK was not an ESO member state). The first VLTI school took place in Les Houches, France, in 2002 and since then VLTI schools have been organised in several locations (France, Germany, Hungary, Poland, Portugal) roughly every two years, the previous one being held in 2018 in Lisbon. The VLTI schools are funded and coordinated through the European Interferometry Initiative (Eii)., Published in The Messenger vol. 185, pp. 28-30, December 2021.

Published
2021
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5. IR Excess of Classical Cepheids Modeled by a Thin Shell of Ionized Gas

Author

Hocdé, Vincent, Nardetto, Nicolas, Lagadec, Eric, Niccolini, Gilles, Domiciano De Souza, Armando, Mérand, Antoine, Kervella, Pierre, Joseph Louis LAGRANGE (LAGRANGE), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, and COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR]
Abstract

International audience; Cepheids are the keystone of the extragalactic distance ladder because their pulsation periods correlate directly with their luminosity, through the Period-Luminosity (PL) relation (Leavitt & Pickering 1912). The discovery of the accelerated expansion of the Universe (Riess et al. 1998; 2011 Nobel prize) is largely based on the Cepheid PL relation. However, the calibration of the PL relation still suffers from systematics errors of at least 2% and it is the largest contributor on the Hubble constant H 0 uncertainty (Riess et al. 2016). These systematics could be partly attributed to the circumstellar envelopes (CSEs) of Cepheids discovered in the last decade using interferometry. Using Spitzer Space Telescope observations, we reconstruct the spectral energy distribution of 5 Cepheids and find an infrared (IR) excess continuum for all of them. We show for the first time that the IR excess can be modeled by a free-free emission due to a thin circumstellar shell of ionized gas in the chromospheric region.

Published
2019

6. CHARA/SPICA: the new 6T visible combiner for the CHARA Array

Author

Kammerer, Jens, Sallum, Stephanie, Sanchez-Bermudez, Joel, Mourard, Denis, Meilland, Anthony, Ibañez Bustos, Romina, Jonak, Juraj, Berio, Philippe, Dejonghe, Julien, Lecron, Daniel, Morand, Frédéric, Salabert, David, Allouche, Fatmé, Anugu, Narsireddy, Bosio, Sandra, Bourges, Laurent, Creevey, Orlagh, Deheuvels, Sébastien, Domiciano de Souza, Armando, Ebrahimkutty, Nayeem, Gies, Doug R., Kubiak, Karolina, Ligi, Roxanne, Ligon, Robert, Mella, Guillaume, Nardetto, Nicolas, Perraut, Karine, Pitiot, Christophe, Rousseau, Sylvain, Vrard, Mathieu, Schaefer, Gail H., Spang, Alain, Turner, Nils, Wittkowski, Markus, and Zumbo, Florian

Published
2024
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7. High resolution of fast-rotating stars across the H-R diagram

Author

Domiciano de Souza, Armando, Joseph Louis LAGRANGE (LAGRANGE), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université de Nice Sophia Antipolis, Université Côte d'Azur, and Farrokh Vakili

Subjects
spectroscopy, observation, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], haute résolution angulaire, modeling, rotation, physique stellaire, spectroscopie, stellar physics, traitement su signal, stellar interferometry, radiation transfer, transfert radiatif, signal processing, high angular resolution, interférométrie stellaire, modélisation
Abstract

Rotation is a fundamental parameter that governs the physical structure and evolution of stars, for example by generating internal circulations of matter and angular momentum, which in turn change the stellar lifetime. Massive stars (spectral types OBA) are those presenting the highest rotation velocities and thus those for which the consequences of rotation are the strongest. On the external layers of the star, fast-rotation induces in particular (1) a flattening (equatorial radius higher than the polar radius) and (2) a gravity darkening (non-uniform distribution of flux, and thus effective temperature, between the poles and the equator). This important modification in the photospheric physical structure can also drive an anisotropic (axisymmetric) mass and angular momentum loss, originating for example the complex circumstellar environments around Be and supergiant B[e] stars. The techniques of high angular and high spectral resolution allow a detailed study of the effects of rotation on the stellar photosphere and circumstellar environment across the H-R diagram. Thanks to these techniques, and in particular to the optical/infrared long-baseline interferometry, our knowledge on the impact of rotation in stellar physics was highly deepened since the beginning of the XXI century. The results described in this Habilitation Thesis are placed in this context and are the fruit a double approach combining both (1) observation, mainly with the ESO-VLT(I) instruments (e.g. NACO, VISIR, MIDI, AMBER, PIONIER) and (2) astrophysical modeling with different codes, including also radiation transfer (CHARRON, HDUST, FRACS). I present, in particular, the results obtained on three fast-rotating stars: Altair (A7V; delta Scuti), Achernar (B6Ve; Be star), and CPD-57° 2874 (supergiant B[e] star).; La rotation est un des paramètres fondamentaux qui gouverne la structure physique et l’évolution des étoiles, par exemple en créant une circulation interne de matière et de moment angulaire, ce qui a aussi pour conséquence de changer le temps de vie de l’étoile. Les étoiles massives (types spectraux OBA) sont celles qui présentent les vitesses de rotation les plus élevées et donc celles où les conséquences de la rotation sont les plus importantes. Sur les couches externes de l’étoile, une rotation rapide engendre en particulier (1) un aplatissement (rayon équatorial plus grand que le rayon polaire) et (2) et un assombrissement gravitationnel (distribution non-uniforme de flux, et donc température effective, entre les pôles et l’équateur). Cette modification importante de la structure physique de la photosphère peut également entraîner une perte de masse et de moment angulaire anisotrope (axis-symétrique), qui donne origine par exemple aux environnements circumstellaires complexes détectés autour des étoiles Be et supergéantes B[e]. Les techniques de haute résolution angulaire et spectrale permettent d’étudier en détail les effets de la rotation sur la photosphère et l’environnement circumstellaire à travers le diagramme H-R. Grâce à ces techniques, et en particulier à l’interférométrie optique/infra-rouge à longue base, nos connaissances sur l’impact de la rotation en physique stellaire ont été fortement approfondies depuis le début du XXIe siècle. Les résultats décrits dans ce mémoire de HDR se placent dans ce contexte et sont le fruit d’une double approche combinant (1) observation, surtout avec des instruments du ESO-VLT(I) (e.g. NACO, VISIR, MIDI, AMBER, PIONIER) et (2) modélisation astrophysique avec différents codes, incluant également le transfert de rayonnement (CHARRON, HDUST, FRACS). Je présente, en particulier, les résultats obtenus sur trois étoiles en rotation rapide : Altaïr (A7V ; delta Scuti), Achernar (B6Ve ; étoile Be), et CPD-57° 2874 (étoile supergéante B[e]).

Published
2014

8. The environment of the fast rotating star Achernar

Author

Domiciano de Souza, Armando, Kervella, P., Moser Faes, D., Dalla Vedova, G., Mérand, A., Le Bouquin, J.-B., Espinosa Lara, F., Rieutord, M., Bendjoya, P., Carciofi, A., Hadjara, M., Millour, F., Vakili, F., Joseph Louis LAGRANGE (LAGRANGE), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), 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), Instituto de Astronomia, Geofisica e Ciencias Atmosfericas da Universidade de Sao Paulo (IAGCAUS), Université de Sao Paulo, European Southern Observatory (ESO), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG ), Centre National d'Études Spatiales [Toulouse] (CNES)-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)-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), Laboratoire Astrophysique de Toulouse-Tarbes (LATT), Centre National de la Recherche Scientifique (CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), 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)-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)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS]Physics [physics], [SDU]Sciences of the Universe [physics], [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2014
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9. Grown-up stars physics with MATISSE

Author

Millour, Florentin, Domiciano De Souza, Armando, Niccolini, Gilles, Hofmann, Karl Heinz, Schertl, Dieter, Stee, Ph, Bendjoya, Philippe, Thévenin, Frédéric, Vakili, Farrokh, Berio, Ph, Lanz, Thierry, Hron, Josef, Matter, Alexis, Cruzalèbes, Pierre, Petrov, Romain, Lopez, Bruno, Chiavassa, Andréa, Weigelt, Gerd, Soulain, A., Khorrami, Z., Meilland, Anthony, Nardetto, Nicolas, Paladini, Claudia, Millour, Florentin, Domiciano De Souza, Armando, Niccolini, Gilles, Hofmann, Karl Heinz, Schertl, Dieter, Stee, Ph, Bendjoya, Philippe, Thévenin, Frédéric, Vakili, Farrokh, Berio, Ph, Lanz, Thierry, Hron, Josef, Matter, Alexis, Cruzalèbes, Pierre, Petrov, Romain, Lopez, Bruno, Chiavassa, Andréa, Weigelt, Gerd, Soulain, A., Khorrami, Z., Meilland, Anthony, Nardetto, Nicolas, and Paladini, Claudia

Abstract

MATISSE represents a great opportunity to image the environment around massive and evolved stars. This will allow one to put constraints on the circumstellar structure, on the mass ejection of dust and its reorganization, and on the dust-nature and formation processes. MATISSE measurements will often be pivotal for the understanding of large multiwavelength datasets on the same targets collected through many high-Angular resolution facilities at ESO like sub-millimeter interferometry (ALMA), near-infrared adaptive optics (NACO, SPHERE), interferometry (PIONIER, GRAVITY), spectroscopy (CRIRES), and mid-infrared imaging (VISIR). Among main sequence and evolved stars, several cases of interest have been identified that we describe in this paper., SCOPUS: cp.p, info:eu-repo/semantics/published

Published
2016

10. Modelling and observation in stellar interferometry

Author

Domiciano de Souza, Armando and Domiciano de Souza, Armando

Subjects
Be phenomenon, haute résolution angulaire, model atmospheres, modélisation d’atmosphères, stellar pulsation, radiative transfer, inhomogénéités photosphériques, phénomène Be, optical long baseline interferometry, Achernar, stellar rotation, rotation stellaire, [SDU.ASTR.SR] Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], pulsation stellaire, transfert radiatif, high angular resolution, interférométrie optique à longue base, photospheric inhomogeneities
Abstract

I present here my thesis researches and results on some mechanisms that govern stellar evolution, in particular rotation, pulsation and stellar activity. For this purpose I developed a numerical model oriented to Optical Long Baseline Interferometry (OLBI) combined to high spectral resolution. Thanks to this model I studied the morphology and the gravity darkening of stars rotating close to their critical velocity. I could then prepare, analyse and interpret our IR interferometric observations on VLTI-VINCI. A major and unique result is the direct measure of the oblateness of the Be star Achernar, which shows an equatorial radius ~50% larger than the polar one, in first approximation. This flattening comes certainly from the photosphere so that I could conclude that the Roche approximation cannot explain our observations. Differential rotation is the proposed alternative hypothesis, with multiple consequences on the transport and loss of the mass and angular momentum. This work motivated a spectro-interferometric study of the differential rotation, notably for VLTI-AMBER, where I show that the Fourier transform of photocenter profiles allow us to determine the differential rotation rate and the 3D orientation of the stellar rotation axis. Finally, I present a few prospective studies concerning the measure, by OLBI, of several kinds of surface inhomogeneities through complex visibility phases, direct imaging by telescope networks, as well as through interferometric Doppler imaging, Dans ce mémoire j'expose mes recherches et résultats sur certains mécanismes qui régissent l’évolution stellaire, en particulier la rotation, la pulsation et l’activité stellaire. Pour cela j'ai développé un outil de modélisation dédié à l'Interférométrie Optique à Longue Base (OLBI) combinée à la haute résolution spectrale. Ce modèle m’a permis d’étudier la morphologie et l’assombrissement gravitationnel des étoiles tournant proche de leur vitesse critique. J’ai pu ainsi préparer, analyser et interpréter des observations en interférométrie IR sur VLTI-VINCI. Un résultat marquant et unique est la mesure directe de l’aplatissement de l’étoile Be Achernar montrant un rayon équatorial ~50% fois plus grand que le rayon polaire, en première approximation. Cet aplatissement se situant sans équivoque au niveau de la photosphère, j’ai pu conclure que l’approximation de Roche ne permet pas d’expliquer nos observations. La rotation différentielle est l’hypothèse alternative proposée, avec des multiples conséquences entre autres sur le transport et sur la perte du moment angulaire et de la masse. Ce travail a motivé une étude théorique de la rotation différentielle par la spectro-interférométrie, sur VLTI-AMBER notamment, où je démontre que la transformée de Fourier des profils de photocentre permet de déterminer le taux de rotation différentielle et l’orientation 3D de l’axe de rotation stellaire. Pour terminer, je présente quelques études prospectives sur la mesure, par OLBI, de diverses formes d'inhomogénéités de surface à partir de la phase des visibilités complexes ou de l'imagerie directe par des réseaux de télescopes, en passant par l'imagerie Doppler interférométrique.

Published
2003

11. A binary engine fuelling HD87643' s complex circumstellar environment, using AMBER/VLTI

Author

Millour, Florentin, Chesneau, Olivier, Borges Fernandes, Marcelo, Meilland, Anthony, Mars, Gilbert, Benoist, C., Thiébaut, Éric, Stee, Philippe, Hofmann, K.-H., Baron, Fabien, Young, John, Bendjoya, Philippe, Carciofi, A. C., Domiciano De Souza, Armando, Driebe, Thomas, Jankov, Slobodan, Kervella, Pierre, Petrov, R. G., Robbe-Dubois, Sylvie, Vakili, Farrokh, Waters, L. B. F. M., Weigelt, Gerd, Max-Planck-Institut für Radioastronomie (MPIFR), Laboratoire Hippolyte Fizeau (FIZEAU), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Département Fresnel (FRESNEL), 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 de Cosmologie, Astrophysique Stellaire & Solaire, de Planétologie et de Mécanique des Fluides (CASSIOPEE), 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), Cavendish Laboratory, University of Cambridge [UK] (CAM), Instituto de Astronomia, Geofísica e Ciências Atmosféricas [São Paulo] (IAG), Universidade de São Paulo = University of São Paulo (USP), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), Université Nice Sophia Antipolis (... - 2019) (UNS), 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 Universidade de São Paulo (USP)

Subjects
Astrophysics - Solar and Stellar Astrophysics, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], FOS: Physical sciences, [PHYS.ASTR.SR]Physics [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Solar and Stellar Astrophysics (astro-ph.SR)
Abstract

International audience; Context. The star HD 87643, exhibiting the “B[e] phenomenon”, has one of the most extreme infrared excesses for this object class. It harbours a large amount of both hot and cold dust, and is surrounded by an extended reflection nebula. Aims. One of our major goals was to investigate the presence of a companion in HD87643. In addition, the presence of close dusty material was tested through a combination of multi-wavelength high spatial resolution observations. Methods. We observed HD 87643 with high spatial resolution techniques, using the near-IR AMBER/VLTI interferometer with baselines ranging from 60 m to 130 m and the mid-IR MIDI/VLTI interferometer with baselines ranging from 25 m to 65 m. These observations are complemented by NACO/VLT adaptive-optics-corrected images in the K and L-bands, ESO-2.2m optical Wide-Field Imager large-scale images in the B, V and R-bands, Results. We report the direct detection of a companion to HD 87643 by means of image synthesis using the AMBER/VLTI instrument. The presence of the companion is confirmed by the MIDI and NACO data, although with a lower confidence. The companion is separated by ∼ 34 mas with a roughly north-south orientation. The period must be large (several tens of years) and hence the orbital parameters are not determined yet. Binarity with high eccentricity might be the key to interpreting the extreme characteristics of this system, namely a dusty circumstellar envelope around the primary, a compact dust nebulosity around the binary system and a complex extended nebula witnessing past violent ejections.

Published
2009

12. 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
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13. VLTI near-IR interferometric observations of Vega-like stars. Radius and age of alpha PsA, beta Leo, beta Pic, ε Eri and tau Cet

Author

Di Folco, Emmanuel, Thévenin, Frédéric, Kervella, Pierre, Domiciano de Souza, Armando, Coudé Du Foresto, Vincent, Segransan, Damien, Morel, Pierre, European Southern Observatory (ESO), Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA), European Southern Observatory, 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, 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, Max-Planck-Institut für Radioastronomie (MPIfR), 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), and Observatoire Astronomique de l'Université de Genève

Subjects
[SDU]Sciences of the Universe [physics], [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract

International audience; We report in this paper the direct interferometric measurement of the angular diameter of five nearby Vega-like stars: alpha PsA, beta Leo, beta Pic, ε Eri and tau Cet. The near-infrared (K and H bands) observations were conducted at the VLTI during the commissioning period with the VINCI instrument and three different baselines ranging from 66 m to 140 m. The five stellar photospheres are resolved and we derive their angular diameters with a 1 to 2% accuracy, except for beta Pic (14%). We discuss the detectability and the influence of a possible small amount of warm circumstellar dust on our measurements. In addition, we have used the stellar evolution code CESAM (Morel \cite{m97}) to compare the computed fundamental parameters to the observed values (linear diameter, luminosity, temperature and chemical abundance). As a result of the simulation, the age of the stars is inferred and found to be in good agreement with previous estimates from various other methods.

Published
2004
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14. Near-IR Observations of Vega-like Stars with the VLTI: beta Pic alpha PsA, ε Eri, and tau Cet

Author

Di Folco, Emmanuel, Kervella, Pierre, Thévenin, Frédéric, Morel, Pierre, Domiciano de Souza, Armando, Coudé Du Foresto, Vincent, 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
[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract

International audience

Published
2003

16. VLTI-AMBER observations of Eta Carinae with high spatial resolution and spectral resolutions of 1,500 and 10,000

Author

Weigelt, Gerd, primary, Petrov, Romain G., additional, Chesneau, Olivier, additional, Davidson, Kris, additional, Domiciano de Souza, Armando, additional, Driebe, Thomas, additional, Foy, Renaud, additional, Fraix-Burnet, Didier, additional, Gull, Ted, additional, Hillier, John D., additional, Hofmann, Karl-Heinz, additional, Kraus, Stefan, additional, Malbet, Fabien, additional, Marconi, Alessandro, additional, Mathias, Philippe, additional, Monin, Jean-Louis, additional, Millour, Florentin, additional, Ohnaka, Keiichi, additional, Rantakyrö, Frederik, additional, Richichi, Andrea, additional, Schertl, Dieter, additional, Schöller, Markus, additional, Stee, Philippe, additional, Testi, Leonardo, additional, and Wittkowski, Markus, additional

Published
2006
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17. VEGA: a visible spectrograph and polarimeter for CHARA - science cases description.

Author

Stee, Philippe, Mourard, Denis, Bonneau, Daniel, Berlioz-Arthaud, Paul, Domiciano de Souza, Armando, Foy, Renaud, Harmanec, Petr, Jankov, Slobodan, Kervella, Pierre, Koubsky, Pavel, Lagarde, Stéphane, Le Bouquin, Jean-Baptiste, Mathias, Philippe, Mérand, Antoine, Nardetto, Nicolas, Petrov, Romain G., Rousselet-Perraut, Karine, Stehle, Chantal, and Weigelt, Gerd

Published
2006
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18. CHARA/SPICA: a six-telescope visible instrument for the CHARA Array

Author

Mérand, Antoine, Sallum, Stephanie, Sanchez-Bermudez, Joel, Mourard, Denis, Berio, Philippe, Pannetier, Cyril, Nardetto, Nicolas, Allouche, Fatmé, Bailet, Christophe, Dejonghe, Julien, Geneslay, Pierre, Jacqmart, Estelle, Lagarde, Stéphane, Lecron, Daniel, Morand, Frédéric, Rousseau, Sylvain, Salabert, David, Spang, Alain, Albrecht, Simon, Anugu, Narsireddy, Bourgès, Laurent, ten Brummelaar, Theo A., Creevey, Orlagh, Deheuvels, Sebastien, Domiciano de Souza, Armando, Gies, Doug, Ligi, Roxanne, Mella, Guillaume, Perraut, Karine, Schaefer, Gail, and Wittkowski, Markus

Published
2022
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19. An interferometric view of hot star disks

Author

Faes, Daniel Moser, Carciofi, Alex C., Domiciano de Souza, Armando, Alex Cavalieri Carciofi, Jon Eric Bjorkman, Samer Kanaan, Pierre Kervella, Ronaldo Savarino Levenhagen, and Armando Domiciano de Souza Junior

Subjects
thesis, stars: magnetic field, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, circumstellar matter, stars: emission-line, Be, Astrophysics - Solar and Stellar Astrophysics, techniques: interferometric, Astrophysics::Solar and Stellar Astrophysics, stars: individual (Achernar), Astrophysics::Earth and Planetary Astrophysics, stars: fundamental parameters, Astrophysics::Galaxy Astrophysics, Solar and Stellar Astrophysics (astro-ph.SR)
Abstract

Optical long baseline interferometry was recently established as a technique capable of resolving stars and their circumstellar environments at the milliarcsecond (mas) resolution level. This high-resolution opens an entire new window to the study of astrophysical systems, providing information inaccessible by other techniques. Astrophysical disks are observed in a wide variety of systems, from galaxies up to planetary rings, commonly sharing similar physical processes. Two particular disk like systems are studied in the thesis: (i) B He-rich stars that exhibits magnetic fields in order of kG and that trap their winds in structures called magnetospheres; and (ii) Be stars, fast rotating stars that create circumstellar viscous disks. This study uses the interferometric technique to investigate both the photosphere proper and the circumstellar environment of these stars. The objective is to combine interferometry with other observational techniques (such as spectroscopy and polarimetry) to perform a complete and well-constrained physical description of these systems. This description is accompanied by radiative transfer models performed by the HDUST code. Keywords: stars: individual (Achernar), stars: fundamental parameters, techniques: interferometric, circumstellar matter, stars: emission-line, Be, stars: magnetic field, Comment: 235* pages, PhD Thesis, Universidade de S\~ao Paulo and Universit\'e Nice Sophia-Antipolis

Published
2015

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