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A Binary Shaped Mask Coronagraph for a Segmented Pupil

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 نشر من قبل Keigo Enya
 تاريخ النشر 2011
  مجال البحث فيزياء
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We present the concept of a binary shaped mask coronagraph applicable to a telescope pupil including obscuration, based on previous works on binary shaped pupil mask by citet{Kasdin2005} and citet{Vanderbei1999}. Solutions with multi-barcode masks which skip over the obscuration are shown for various types of pupil of telescope, such as SUBARU, JWST, SPICA, and other examples. The number of diffraction tails in the point spread function of the coronagraphic image is reduced to two, thus offering a large discovery angle. The concept of mask rotation is also presented, which allows post-processing removal of diffraction tails and provides a 360$^{circ}$ continuous discovery angle. It is suggested that the presented concept offers solutions which potentially allow large telescopes with segmented pupil in future to be used as platforms for an coronagraph.

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