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Bispectrum speckle interferometry of the B[e] star MWC 349A

K. -H. Hofmann·Y. Balega·N. R. Ikhsanov·A. S. Miroshnichenko·G. Weigelt
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Abstract

We present the results of bispectrum speckle interferometry of the B[e] star MWC 349A obtained with the SAO 6m telescope. Our diffraction-limited J-, H-, and K-band images (resolutions 43--74 mas) suggest the star is surrounded by a circumstellar disk seen almost edge-on. The observed visibility shape is consistent with a two-component elliptical disk model, probably corresponding to the gaseous and dusty components of the disk. We show that the classification of the object as a pre-main-sequence star or a young planetary nebula is problematic. An analysis of the uncertainties in the basic parameter determination lead us to the conclusion that MWC 349A is probably either a B[e] supergiant or a binary system, in which the B[e]-companion dominates the observed properties.

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K. -H. Hofmann, Y. Balega, N. R. Ikhsanov, A. S. Miroshnichenko, G. Weigelt. 2002-09-25. Bispectrum speckle interferometry of the B[e] star MWC 349A. https://doi.org/10.1051/0004-6361%3A20021351

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