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Multi-wavelength diffraction-limited imaging of the evolved carbon star IRC +10216, II

P. G. Tuthill·J. D. Monnier·W. C. Danchi
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Abstract

High angular resolution images of IRC +10216 taken at various bandpasses within the near-infrared h, k & l bands are presented. The maps have the highest angular resolution yet recovered, and were reconstructed from interferometric measurements obtained at the Keck 1 telescope in 1997 December and 1998 April, forming a subset of a 7-epoch monitoring program presented earlier [paper 1]. Systematic changes with observing wavelength are found and discussed in context of present geometrical models for the circumstellar envelope. With these new high-resolution, multi-wavelength data and contemporaneous photometry, we also re-visit the hypothesis that the bright compact Core of the nebula (component `A') marks the location of the central carbon star. We find that directly measured properties of the Core (angular size, flux density, color temperature) are consistent with a reddened carbon star photosphere (line-of-sight tau=5.3).

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P. G. Tuthill, J. D. Monnier, W. C. Danchi. 2005-03-09. Multi-wavelength diffraction-limited imaging of the evolved carbon star IRC +10216, II. https://doi.org/10.1086/428932

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