Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Cold optical design for the Large Aperture Simons Observatory telescope   The Simons Observatory will consist of a single large (6 m diameter)
telescope and a number of smaller (0.5 m diameter) refracting telescopes
designed to measure the polarization of the Cosmic Microwave Background to
unprecedented accuracy. The large aperture telescope is the same design as the
CCAT-prime telescope, a modified Crossed Dragone design with a field-of-view of
over 7.8 degrees diameter at 90 GHz. This paper presents an overview of the
cold reimaging optics for this telescope and what drove our choice of 350-400
mm diameter silicon lenses in a 2.4 m cryostat over other possibilities. We
will also consider the future expandability of this design to CMB Stage-4 and
beyond.

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The categories of this paper are: comp-gas
23
The categories of this paper are: solv-int
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The categories of this paper are: bayes-an
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The categories of this paper are: adap-org
12
The categories of this paper are: nucl-th
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The categories of this paper are: hep-th
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The categories of this paper are: hep-lat
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The categories of this paper are: q-alg
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The categories of this paper are: mtrl-th
3
The categories of this paper are: physics
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The categories of this paper are: supr-con
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The categories of this paper are: eess
2
The categories of this paper are: math
20
The categories of this paper are: acc-phys
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The categories of this paper are: patt-sol
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The categories of this paper are: q-fin