E-resources
-
Weigelt, G; K.-H. Hofmann; Schertl, D; Lopez, B; Petrov, R G; Lagarde, S; Ph. Berio; Jaffe, W; Th. Henning; Millour, F; Meilland, A; Allouche, F; Robbe-Dubois, S; Matter, A; Cruzalèbes, P; Hillier, D J; Russell, C M P; Madura, T; Gull, T R; Corcoran, M F; Damineli, A; Moffat, A F J; Morris, P W; Richardson, N D; Paladini, C; Schöller, M; Mérand, A; Glindemann, A; Beckmann, U; Heininger, M; Bettonvil, F; Zins, G; Woillez, J; Bristow, P; Sanchez-Bermudez, J; Ohnaka, K; Kraus, S; Mehner, A; Wittkowski, M; Hummel, C A; Stee, P; Vakili, F; Hartman, H; Navarete, F; Hamaguchi, K; Espinoza-Galeas, D A; Stevens, I R; R. van Boekel; Wolf, S; Hogerheijde, M R; Dominik, C; J.-C. Augereau; Pantin, E; L. B. F. M. Waters; Meisenheimer, K; Varga, J; Klarmann, L; V. Gámez Rosas; Burtscher, L; Leftley, J; Isbell, J W; Hocdé, V; Yoffe, G; Kokoulina, E; Hron, J; Groh, J; Kreplin, A; Th. Rivinius; W.-J. de Wit; W.-C. Danchi; A. Domiciano de Souza; Drevon, J; Labadie, L; Connot, C; Nußbaum, E; Lehmitz, M; Antonelli, P; Graser, U; Leinert, C
Astronomy & astrophysics, 08/2021, Volume: 652Journal Article
Context. Eta Carinae is a highly eccentric, massive binary system (semimajor axis ~15.5 au) with powerful stellar winds and a phase-dependent wind-wind collision (WWC) zone. The primary star, η Car A, is a luminous blue variable (LBV); the secondary, η Car B, is a Wolf-Rayet or O star with a faster but less dense wind. Aperture-synthesis imaging allows us to study the mass loss from the enigmatic LBV η Car. Understanding LBVs is a crucial step toward improving our knowledge about massive stars and their evolution. Aims. Our aim is to study the intensity distribution and kinematics of η Car’s WWC zone. Methods. Using the VLTI-MATISSE mid-infrared interferometry instrument, we perform Brα imaging of η Car’s distorted wind. Results. We present the first VLTI-MATISSE aperture-synthesis images of η Car A’s stellar windin several spectral channels distributed across the Brα 4.052 μm line (spectral resolving power R ~ 960). Our observations were performed close to periastron passage in February 2020 (orbital phase ~ 14.0022). The reconstructed iso-velocity images show the dependence of the primary stellar wind on wavelength or line-of-sight (LOS) velocity with a spatial resolution of 6 mas (~14 au). The radius of the faintest outer wind regions is ~26 mas (~60 au). At several negative LOS velocities, the primary stellar wind is less extended to the northwest than in other directions. This asymmetry is most likely caused by the WWC. Therefore, we see both the velocity field of the undisturbed primary wind and the WWC cavity. In continuum spectral channels, the primary star wind is more compact than in line channels. A fit of the observed continuum visibilities with the visibilities of a stellar wind CMFGEN model (CMFGEN is an atmosphere code developed to model the spectra of a variety of objects) provides a full width at half maximum fit diameter of the primary stellar wind of 2.84 ± 0.06 mas (6.54 ± 0.14 au). We comparethe derived intensity distributions with the CMFGEN stellar wind model and hydrodynamic WWC models.
Author
Shelf entry
Permalink
- URL:
Impact factor
Access to the JCR database is permitted only to users from Slovenia. Your current IP address is not on the list of IP addresses with access permission, and authentication with the relevant AAI accout is required.
Year | Impact factor | Edition | Category | Classification | ||||
---|---|---|---|---|---|---|---|---|
JCR | SNIP | JCR | SNIP | JCR | SNIP | JCR | SNIP |
Select the library membership card:
If the library membership card is not in the list,
add a new one.
DRS, in which the journal is indexed
Database name | Field | Year |
---|
Links to authors' personal bibliographies | Links to information on researchers in the SICRIS system |
---|
Source: Personal bibliographies
and: SICRIS
The material is available in full text. If you wish to order the material anyway, click the Continue button.