(Image with
different colour table)
76 mas Speckle-Masking
Interferometry of IRC+10216
with the
SAO 6m Telescope: Evidence for a clumpy shell
structure
G. Weigelt, Y. Balega, T. Blöcker, A.J. Fleischer, R. Osterbart
and J.M Winters
Astronomy and Astrophysics 333, L51-L54 (1998)
Abstract.
We present the first
K'-band image of the carbon star IRC+10216 with
76 mas resolution. The diffraction-limited image was reconstructed
from 6m telescope speckle data using the speckle masking bispectrum
method. The image shows that the dust shell of IRC+10216 is
extremely clumpy. Five individual clouds within a 210 mas radius
of the central star have been resolved for the first time.
On the basis of consistent theoretical models we argue that these
structures are produced by circumstellar dust formation.
The fragmentation of the shell structure gives most likely
direct evidence for an inhomogeneous mass-loss process which may be
interpreted in terms of large-scale surface convection-cells
(Schwarzschild 1975) being a common phenomenon for red giants.