Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Pions in Proton Structure and Everywhere Else   The pion cloud is important in nuclear physics and in a variety of low-energy
hadronic phenomena. We argue that it is natural to expect it to also be
important in lepton-proton deep inelastic scattering and Drell-Yan studies of
proton structure. We compute the necessary consequences of the pion cloud in
connection with the recent SeaQuest data. The effects are detailed by using the
exact kinematics of the experiment. Excellent agreement with the measurements
is obtained. Thus the universality of pionic effects is understood.

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The categories of this paper are: dg-ga
34
The categories of this paper are: chem-ph
16
The categories of this paper are: stat
28
The categories of this paper are: alg-geom
19
The categories of this paper are: eess
6
The categories of this paper are: astro-ph
14
The categories of this paper are: math-ph
13
The categories of this paper are: quant-ph
33
The categories of this paper are: plasm-ph
7
The categories of this paper are: hep-th
29
The categories of this paper are: funct-an
5
The categories of this paper are: gr-qc
4
The categories of this paper are: cond-mat
9
The categories of this paper are: nlin
17
The categories of this paper are: q-fin
10
The categories of this paper are: q-bio