Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: An estimate of the eta and eta-prime meson masses in Nf=2+1 lattice QCD   Masses of the eta and eta-prime mesons are estimated in Nf=2+1 lattice QCD
with the non-perturbatively O(a) improved Wilson quark action and the Iwasaki
RG-improved gluon action, using CP-PACS/JLQCD configurations on a 16^3 x 32
lattice at beta=1.83 (lattice spacing is 0.122 fm). We apply a stochastic noise
estimator technique combined with smearing method to evaluate correlators among
flavor SU(2) singlet pseudoscalar operators and strange pseudoscalar operators
for 10 combinations of up/down and strange quark masses. The correlator matrix
is then diagonalized to identify signals for mass eigenstates. Masses of the
ground state and the first excited state extrapolated to the physical point are
m_eta= 0.545(16) GeV and m_eta-prime= 0.871(46) GeV, being close to the
experimental values of the eta and eta-prime masses.

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The categories of this paper are: astro-ph
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The categories of this paper are: comp-gas
36
The categories of this paper are: cmp-lg
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The categories of this paper are: adap-org
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The categories of this paper are: q-bio
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The categories of this paper are: alg-geom
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The categories of this paper are: math
33
The categories of this paper are: plasm-ph
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The categories of this paper are: cond-mat
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The categories of this paper are: mtrl-th
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The categories of this paper are: chao-dyn
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The categories of this paper are: chem-ph
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The categories of this paper are: supr-con
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The categories of this paper are: quant-ph
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The categories of this paper are: cs
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The categories of this paper are: ao-sci