Spatial Distributions of Multiple Dust Components in the Ppn/pn Dust Shells
نویسندگان
چکیده
We investigate spatial distributions of specific dust components in the circumstellar shells of a proto-planetary nebula candidate, HD 179821, and a planetary nebula, BD+30◦3639, by means of spectral imaging. With high-resolution ground-based images and ISO spectra in the midinfrared, we can derive “dust feature only” maps by subtracting synthesized continuum maps from the observed images at the feature wavelength. Such spatially detailed information will help to develop models for the evolution of dust grains around evolved stars.
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