Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: phi-meson production in proton-antiproton annihilation   Apparent channel-dependent violations of the OZI rule in nucleon-antinucleon
annihilation reactions are discussed in the presence of an intrinsic
strangeness component in the nucleon. Admixture of strange-antistrange quark
pairs in the nucleon wave function enables the direct coupling to the phi-meson
in the annihilation channel without violating the OZI rule. Three forms are
considered in this work for the strangeness content of the proton wave
function, namely, the uud cluster with a strange-antistrange sea quark
component, kaon-hyperon clusters based on a simple chiral quark model, and the
pentaquark picture. Nonrelativistic quark model calculations reveal that the
strangeness magnetic moment and the strangeness contribution to the proton spin
from the first two models are consistent with recent experimental data. For the
third model, the uuds subsystem with the configurations FS[31]F[211]S[22] and
FS[31]F[31]S[22] leads to negative values for the strangeness magnetic moment
and the strangeness contribution to the proton spin. With effective quark line
diagrams incorporating the 3P0 quark model we give estimates for the branching
ratios of the proton-antiproton annihilation reactions at rest to two mesons.
Results for the branching ratios of phi-meson production from atomic
proton-antiproton s-wave states are for the first and third model found to be
strongly channel dependent, in good agreement with measured rates.

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The categories of this paper are: q-fin
18
The categories of this paper are: econ
15
The categories of this paper are: nucl-ex
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The categories of this paper are: alg-geom
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The categories of this paper are: acc-phys
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The categories of this paper are: solv-int
8
The categories of this paper are: hep-ex
37
The categories of this paper are: supr-con
7
The categories of this paper are: hep-th
4
The categories of this paper are: cond-mat
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The categories of this paper are: chem-ph
35
The categories of this paper are: mtrl-th
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The categories of this paper are: hep-lat
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The categories of this paper are: bayes-an
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The categories of this paper are: dg-ga
6
The categories of this paper are: astro-ph