Dans la même rubrique :
Fringes have been recorded (23 March 2004)
We wish you a merry christmas - and a happy new year !
First laboratory fringes on AMBER at Paranal (10 March 2004)
VLT spots the largest hypergiant star
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Astronomy & Astrophysics series of articles on first AMBER/VLTI results
AMBER has been commissionned with pair and triplet of 8m telescopes
AMBER Scientific Workshop
Un téléobjectif géant pour observer le ciel...
AMBER scrutinizes the inner region of the young star MWC 147
AMBER discovers a companion to HD87643 by image-synthesis
17 septembre 2009, par
- Zoom-in into the core of HD87643
- This figure illustrate the wide range of scales covered by this study : left is the wide field image showing the large-scale nebula, middle is the high-resolution NACO adaptive optics image, and right is the higher-resolution synthetised image of the AMBER instrument, revealing the companion star to the main star.
B[e] stars are B-type stars with emission lines and a large infrared excess betraying the presence of dust in their vicinity. HD87643 is one of the most extreme example of this type of stars, as its infrared excess is much larger than the one of any other B[e] stars. Using a wide range of ESO instruments, a team led by F. Millour gave a new insight into this puzzling star.
By observing in the infrared bands H (1.6-1.8 microns) and K (1.95-2.45 microns), they were able to image the innermost dusty regions of this star, unveiling for the first time and without any doubt a stellar companion to the main star. In addition, the main star (seen in the South of the AMBER image) was partly resolved by AMBER, revealing that it is enshrouded in a compact dusty disk. Comparisons with NACO adaptive-optics images revealed that the whole system itself is embedded in a dusty environment. Finally, Wide-Field Images showed arc-like structures in the nebula surrounding HD87643, which may be linked to the central binary star.
As a conclusion, this study of HD87643 give a totally new view of the system : two dust-enshrouded stars embedded in a dense dusty nebula, orbiting in a very eccentric orbit which might be at the origin of periodic violent ejections seen in the nebula.
- A binary engine fuelling HD87643’s complex circumstellar environment, using AMBER/VLTI
F. Millour, O. Chesneau, M. Borges Fernandes, A. Meilland et al.
2009, A&A in press (arXiv:0908.0227)
- ESO press release
- ESOcast video