Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Impact of dijet and D-meson data from 5.02 TeV p+Pb collisions on
  nuclear PDFs   We discuss the new constraints on gluon parton distribution function (PDF) in
lead nucleus, derivable with the Hessian PDF reweighting method from the 5.02
TeV p+Pb measurements of dijet (CMS) and $D^0$-meson (LHCb) nuclear
modification ratios. The impact is found to be significant, placing stringent
constraints in the mid- and previously unconstrained small-$x$ regions. The CMS
dijet data confirm the existence of gluon anti-shadowing and the onset of
small-$x$ shadowing, as well as reduce the gluon PDF uncertainties in the
larger-$x$ region. The gluon constraints from the LHCb $D^0$ data, reaching
down to $x \sim 10^{-5}$ and derived in a NLO perturbative QCD approach,
provide a remarkable reduction of the small-$x$ uncertainties with a strong
direct evidence of gluon shadowing. Furthermore, we find a good description of
the data even down to zero $D^0$-meson transverse momentum within a purely
DGLAP-based approach without a need for imposing any non-linear effects.
Importantly, the constraints obtained from the dijet and $D^0$ data are
mutually fully consistent, supporting the universality of nuclear PDFs in
hard-scattering processes.

13
The categories of this paper are: quant-ph
28
The categories of this paper are: alg-geom
9
The categories of this paper are: nlin
7
The categories of this paper are: hep-th
3
The categories of this paper are: physics
30
The categories of this paper are: q-alg
5
The categories of this paper are: gr-qc
33
The categories of this paper are: plasm-ph
18
The categories of this paper are: econ
27
The categories of this paper are: comp-gas
31
The categories of this paper are: ao-sci
29
The categories of this paper are: funct-an
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The categories of this paper are: nucl-ex
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The categories of this paper are: dg-ga
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The categories of this paper are: patt-sol
19
The categories of this paper are: eess