dc.contributor.author | Weigelt, G | |
dc.contributor.author | Kraus, S | |
dc.contributor.author | Driebe, T | |
dc.contributor.author | Petrov, RG | |
dc.contributor.author | Hofmann, K-H | |
dc.contributor.author | Millour, F | |
dc.contributor.author | Chesneau, O | |
dc.contributor.author | Schertl, D | |
dc.contributor.author | Malbet, F | |
dc.contributor.author | Hillier, JD | |
dc.contributor.author | Gull, T | |
dc.contributor.author | Davidson, K | |
dc.contributor.author | Domiciano de Souza, A | |
dc.contributor.author | Antonelli, P | |
dc.contributor.author | Beckmann, U | |
dc.contributor.author | Bresson, Y | |
dc.contributor.author | Chelli, A | |
dc.contributor.author | Dugué, M | |
dc.contributor.author | Duvert, G | |
dc.contributor.author | Gennari, S | |
dc.contributor.author | Glück, L | |
dc.contributor.author | Kern, P | |
dc.contributor.author | Lagarde, S | |
dc.contributor.author | Le Coarer, E | |
dc.contributor.author | Lisi, F | |
dc.contributor.author | Perraut, K | |
dc.contributor.author | Puget, P | |
dc.contributor.author | Rantakyrö, F | |
dc.contributor.author | Robbe-Dubois, S | |
dc.contributor.author | Roussel, A | |
dc.contributor.author | Tatulli, E | |
dc.contributor.author | Zins, G | |
dc.contributor.author | Accardo, M | |
dc.contributor.author | Acke, B | |
dc.contributor.author | Agabi, K | |
dc.contributor.author | Altariba, E | |
dc.contributor.author | Arezki, B | |
dc.contributor.author | Aristidi, E | |
dc.contributor.author | Baffa, C | |
dc.contributor.author | Behrend, J | |
dc.contributor.author | Blöcker, T | |
dc.contributor.author | Bonhomme, S | |
dc.contributor.author | Busoni, S | |
dc.contributor.author | Cassaing, F | |
dc.contributor.author | Clausse, J-M | |
dc.contributor.author | Colin, J | |
dc.contributor.author | Connot, C | |
dc.contributor.author | Delboulbé, A | |
dc.contributor.author | Feautrier, P | |
dc.contributor.author | Ferruzzi, D | |
dc.contributor.author | Forveille, T | |
dc.contributor.author | Fossat, E | |
dc.contributor.author | Foy, R | |
dc.contributor.author | Fraix-Burnet, D | |
dc.contributor.author | Gallardo, A | |
dc.contributor.author | Giani, E | |
dc.contributor.author | Gil, C | |
dc.contributor.author | Glentzlin, A | |
dc.contributor.author | Heiden, M | |
dc.contributor.author | Heininger, M | |
dc.contributor.author | Hernandez Utrera, O | |
dc.contributor.author | Kamm, D | |
dc.contributor.author | Kiekebusch, M | |
dc.contributor.author | Le Contel, D | |
dc.contributor.author | Le Contel, J-M | |
dc.contributor.author | Lesourd, T | |
dc.contributor.author | Lopez, B | |
dc.contributor.author | Lopez, M | |
dc.contributor.author | Magnard, Y | |
dc.contributor.author | Marconi, A | |
dc.contributor.author | Mars, G | |
dc.contributor.author | Martinot-Lagarde, G | |
dc.contributor.author | Mathias, P | |
dc.contributor.author | Mège, P | |
dc.contributor.author | Monin, J-L | |
dc.contributor.author | Mouillet, D | |
dc.contributor.author | Mourard, D | |
dc.contributor.author | Nussbaum, E | |
dc.contributor.author | Ohnaka, K | |
dc.contributor.author | Pacheco, J | |
dc.contributor.author | Perrier, C | |
dc.contributor.author | Rabbia, Y | |
dc.contributor.author | Rebattu, S | |
dc.contributor.author | Reynaud, F | |
dc.contributor.author | Richichi, A | |
dc.contributor.author | Robini, A | |
dc.contributor.author | Sacchettini, M | |
dc.contributor.author | Schöller, M | |
dc.contributor.author | Solscheid, W | |
dc.contributor.author | Spang, A | |
dc.contributor.author | Stee, P | |
dc.contributor.author | Stefanini, P | |
dc.contributor.author | Tallon, M | |
dc.contributor.author | Tallon-Bosc, I | |
dc.contributor.author | Tasso, D | |
dc.contributor.author | Testi, L | |
dc.contributor.author | Vakili, F | |
dc.contributor.author | von der Lühe, O | |
dc.contributor.author | Valtier, J-C | |
dc.contributor.author | Vannier, M | |
dc.contributor.author | Ventura, N | |
dc.contributor.author | Weis, K | |
dc.contributor.author | Wittkowski, M | |
dc.date.accessioned | 2018-01-15T11:37:39Z | |
dc.date.issued | 2006-09-12 | |
dc.description.abstract | Aims. We present the first NIR spectro-interferometry of the LBV η Carinae. The observations were performed with the AMBER instrument of
the ESO Very Large Telescope Interferometer (VLTI) using baselines from 42 to 89 m. The aim of this work is to study the wavelength dependence
of η Car’s optically thick wind region with a high spatial resolution of 5 mas (11 AU) and high spectral resolution.
Methods. The observations were carried out with three 8.2 m Unit Telescopes in the K-band. The raw data are spectrally dispersed interferograms
obtained with spectral resolutions of 1500 (MR-K mode) and 12 000 (HR-K mode). The MR-K observations were performed in the wavelength
range around both the He i 2.059 µm and the Brγ 2.166 µm emission lines, the HR-K observations only in the Brγ line region.
Results. The spectrally dispersed AMBER interferograms allow the investigation of the wavelength dependence of the visibility, differential
phase, and closure phase of η Car. In the K-band continuum, a diameter of 4.0±0.2 mas (Gaussian FWHM, fit range 28–89 m baseline length) was
measured for η Car’s optically thick wind region. If we fit Hillier et al. (2001, ApJ, 553, 837) model visibilities to the observed AMBER visibilities,
we obtain 50% encircled-energy diameters of 4.2, 6.5 and 9.6 mas in the 2.17 µm continuum, the He i, and the Brγ emission lines, respectively. In
the continuum near the Brγ line, an elongation along a position angle of 120◦±15◦ was found, consistent with previous VINCI/VLTI measurements
by van Boekel et al. (2003, A&A, 410, L37). We compare the measured visibilities with predictions of the radiative transfer model of Hillier et al.
(2001), finding good agreement. Furthermore, we discuss the detectability of the hypothetical hot binary companion. For the interpretation of the
non-zero differential and closure phases measured within the Brγ line, we present a simple geometric model of an inclined, latitude-dependent
wind zone. Our observations support theoretical models of anisotropic winds from fast-rotating, luminous hot stars with enhanced high-velocity
mass loss near the polar regions. | en_GB |
dc.description.sponsorship | The AMBER project4 was founded by the French Centre National de la
Recherche Scientifique (CNRS), the Max Planck Institute für Radioastronomie
(MPIfR) in Bonn, the Osservatorio Astrofisico di Arcetri (OAA) in Firenze,
the French Region "Provence Alpes Côte D’Azur" and the European Southern
Observatory (ESO). The CNRS funding has been made through the Institut
National des Sciences de l’Univers (INSU) and its Programmes Nationaux
(ASHRA, PNPS, PNP).
The OAA co-authors acknowledge partial support from MIUR grants to the
Arcetri Observatory: A LBT interferometric arm, and analysis of VLTI interferometric
data and From Stars to Planets: accretion, disk evolution and
planet formation and from INAF grants to the Arcetri Observatory Stellar and
Extragalactic Astrophysics with Optical Interferometry. C. Gil work was supported
in part by the Fundação para a Ciência e a Tecnologia through project
POCTI/CTE-AST/55691/2004 from POCTI, with funds from the European program
FEDER. | en_GB |
dc.identifier.citation | Astronomy and Astrophysics, 2007, Vol. 464, Number 1, pp. 87-106 | en_GB |
dc.identifier.doi | 10.1051/0004-6361:20065577 | |
dc.identifier.uri | http://hdl.handle.net/10871/30980 | |
dc.language.iso | en | en_GB |
dc.publisher | EDP Sciences | en_GB |
dc.rights | © ESO 2007 | en_GB |
dc.subject | stars: individual | en_GB |
dc.subject | η Carinae – stars | en_GB |
dc.subject | mass-loss, emission-line Be, circumstellar matter, winds, outflows – infrared | en_GB |
dc.subject | stars – techniques | en_GB |
dc.subject | interferometric | en_GB |
dc.title.alternative | Near-Infrared interferometry of η Carinae with high spatial and spectral resolution using the VLTI and the AMBER instrument | en_GB |
dc.title | Near-infrared interferometry of η Carinae with spectral resolutions of 1 500 and 12 000 using AMBER/VLTI | en_GB |
dc.type | Article | en_GB |
dc.date.available | 2018-01-15T11:37:39Z | |
dc.identifier.issn | 0004-6361 | |
dc.description | This is the author accepted manuscript. The final version is available from EDP Sciences via the DOI in this record. | en_GB |
dc.identifier.journal | Astronomy and Astrophysics | en_GB |