Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Calabi-Yau Duals for CHL Strings   We find M-theory (Type IIA) duals for compactifications of the 9d CHL string
to 5d (4d) on K3 (K3 x S^1). The IIA duals are Calabi-Yau orbifolds with
nontrivial RR U(1) backgrounds turned on.

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The categories of this paper are: patt-sol
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The categories of this paper are: supr-con
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The categories of this paper are: comp-gas
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The categories of this paper are: solv-int
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The categories of this paper are: dg-ga
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The categories of this paper are: econ
14
The categories of this paper are: math-ph
34
The categories of this paper are: chem-ph
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The categories of this paper are: bayes-an
1
The categories of this paper are: cs
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The categories of this paper are: nucl-ex
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The categories of this paper are: quant-ph
2
The categories of this paper are: math
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The categories of this paper are: funct-an
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The categories of this paper are: q-bio
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The categories of this paper are: adap-org