Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Recent progress in Nuclear Parton Distributions   The determination of the parton distribution functions (PDFs) is crucial for
a complete understanding of the protons and neutrons that make most of the
visible matter in the universe. Years of dedicated studies have yielded a quite
precise knowledge of the behavior of partons moving collinearly within a
proton. However Deep Inelastic Scattering (DIS) experiments off nuclei have
shown a non-trivial difference with respect to DIS in protons, hinting that the
partons in a nuclear medium do not behave the same way as in a free proton. In
this work we will discuss the latest results in nuclear parton distribution
functions (nPDFs) and how data from planned future experiments can help broaden
our understanding of the nPDFs.

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The categories of this paper are: econ
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The categories of this paper are: q-bio
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The categories of this paper are: q-fin
5
The categories of this paper are: gr-qc
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The categories of this paper are: eess
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The categories of this paper are: astro-ph
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The categories of this paper are: plasm-ph
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The categories of this paper are: patt-sol
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The categories of this paper are: hep-th
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The categories of this paper are: atom-ph
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The categories of this paper are: q-alg
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The categories of this paper are: nlin
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The categories of this paper are: hep-ex
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The categories of this paper are: adap-org
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The categories of this paper are: bayes-an
1
The categories of this paper are: cs