We model the spectral energy distribution (SED) from the mid-infrared to submillimeter of the ringlike disk of HR 4796A, the dustiest A-type star. We consider dust made of either coagulated but otherwise unaltered protostellar interstellar grains or grains that are highly processed in a protostellar/protoplanetary nebula with silicate dust annealed and carbon dust oxidized. Both types of dust are successful in reproducing the observed SED, provided that the grains are highly fluffy, with a vacuum volume fraction of ~90%. We find no evidence for the existence of a hot "zodiacal dust" component a few astronomical units from the star, which was suggested by previous workers to account for the 10 μm wavelength emission.
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