Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Even parity excitations of the nucleon in lattice QCD   We study the spectrum of the even parity excitations of the nucleon in
quenched lattice QCD. We extend our earlier analysis by including an expanded
basis of nucleon interpolating fields, increasing the physical size of the
lattice, including more configurations to enhance statistics and probing closer
to the chiral limit. With a review of world lattice data, we conclude that
there is little evidence of the Roper resonance in quenched lattice QCD.

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The categories of this paper are: cs
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The categories of this paper are: q-bio
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The categories of this paper are: nlin
25
The categories of this paper are: patt-sol
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The categories of this paper are: math-ph
32
The categories of this paper are: atom-ph
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The categories of this paper are: q-fin
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The categories of this paper are: acc-phys
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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: q-alg
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The categories of this paper are: supr-con
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The categories of this paper are: stat
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The categories of this paper are: eess
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The categories of this paper are: physics
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The categories of this paper are: nucl-ex