High angular resolution stellar imaging with occultations from the Cassini spacecraft – II. Kronocyclic tomography
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چکیده
We present an advance in the use of Cassini observations of stellar occultations by the rings of Saturn for stellar studies. Stewart et al. demonstrated the potential use of such observations for measuring stellar angular diameters. Here, we use these same observations, and tomographic imaging reconstruction techniques, to produce two-dimensional images of complex stellar systems. We detail the determination of the basic observational reference frame. A technique for recovering model-independent brightness profiles for data from each occulting edge is discussed, along with the tomographic combination of these profiles to build an image of the source star. Finally, we demonstrate the technique with recovered images of the α Centauri binary system and the circumstellar environment of the evolved late-type giant star, Mira.
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تاریخ انتشار 2015