SIMBAD references

We report on the results of modeling of the dust cloud around Fomalhaut to fit the existing far-infrared and submillimeter data from the Kuiper Airborne Observatory (KAO), IRAS, and the James Clerk Maxwell Telescope (JCMT). We assumed an optically and spatially thin disk with the following free parameters: inner and outer radii, power-law surface-density gradient, and a simple-grain model that characterized the emissivity as flat shortward of a transition wavelength and decreasing linearly with wavelength beyond that. We also explored two other parameterizations of the models to try to find parameters that were better defined by the existing data. We analyzed the results of the modeling with Bayesian methods for deriving the probabilities of the model parameters. We find that we can place significant constraints on the location of the dust but, contrary to previous suggestions, not its density gradient within the distribution. We confirm previous suggestions that the dust must have an emissivity dependence that does not decrease significantly with wavelength until longward of λ∼80 µm. The inclination of the dust disk is moderately well constrained close to the range previously suggested, θ=65°±15°. Our models also reproduce well the total submillimeter flux with the simple assumption of a λ^–1 emissivity law in the submillimeter region.