Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Structure of the Nucleon: Elastic Electromagnetic Form Factors   Precise proton and neutron form factor measurements at Jefferson Lab, using
spin observables, have recently made a significant contribution to the
unraveling of the internal structure of the nucleon. Accurate experimental
measurements of the nucleon form factors are a test-bed for understanding how
the nucleon's static properties and dynamical behavior emerge from QCD, the
theory of the strong interactions between quarks. There has been enormous
theoretical progress, since the publication of the Jefferson Lab proton form
factor ratio data, aiming at reevaluating the picture of the nucleon. We will
review the experimental and theoretical developments in this field and discuss
the outlook for the future.

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The categories of this paper are: quant-ph
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The categories of this paper are: comp-gas
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The categories of this paper are: alg-geom
11
The categories of this paper are: hep-lat
34
The categories of this paper are: chem-ph
31
The categories of this paper are: ao-sci
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The categories of this paper are: q-fin
30
The categories of this paper are: q-alg
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The categories of this paper are: solv-int
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The categories of this paper are: patt-sol
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The categories of this paper are: chao-dyn
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The categories of this paper are: hep-th
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The categories of this paper are: q-bio
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The categories of this paper are: physics
0
The categories of this paper are: hep-ph
32
The categories of this paper are: atom-ph