Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A Coronagraph with a Band-Limited Mask for Finding Terrestrial Planets   Several recent designs for planet-finding telescopes use coronagraphs
operating at visible wavelengths to suppress starlight along the telescope's
optical axis while transmitting any off-axis light from circumstellar material.
We describe a class of graded coronagraphic image masks that can, in principle,
provide perfect elimination of on-axis light, while simultaneously maximizing
the Lyot stop throughput and angular resolution. These ``band-limited'' masks
operate on the intensity of light in the image plane, not the phase. They can
work with almost any entrance pupil shape, provided that the entrance pupil
transmissivity is uniform, and can be combined with an apodized Lyot stop to
reduce the sensitivity of the coronagraph to imperfections in the image mask.
We discuss some practical limitations on the dynamic range of coronagraphs in
the context of a space-based terrestrial planet finder (TPF) telescope, and
emphasize that fundamentally, the optical problem of imaging planets around
nearby stars is a matter of precision fabrication and control, not Fraunhofer
diffraction theory.

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The categories of this paper are: eess
34
The categories of this paper are: chem-ph
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The categories of this paper are: solv-int
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The categories of this paper are: alg-geom
2
The categories of this paper are: math
35
The categories of this paper are: mtrl-th
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The categories of this paper are: econ
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The categories of this paper are: chao-dyn
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The categories of this paper are: hep-lat
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The categories of this paper are: adap-org
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The categories of this paper are: dg-ga
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The categories of this paper are: nucl-th
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The categories of this paper are: bayes-an
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The categories of this paper are: hep-th
0
The categories of this paper are: hep-ph
33
The categories of this paper are: plasm-ph