Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Light-by-light scattering in ultraperipheral PbPb collisions at the
  Large Hadron Collider   We calculate cross sections for diphoton production in (semi)exclusive $PbPb$
collisions, relevant for the LHC. The calculation is based on equivalent photon
approximation in the impact parameter space. The cross sections for elementary
$\gamma \gamma \to \gamma \gamma$ subprocess are calculated including two
different mechanisms. We take into account box diagrams with leptons and quarks
in the loops. In addition, we consider a vector-meson dominance (VDM-Regge)
contribution with virtual intermediate hadronic (vector-like) excitations of
the photons. We get much higher cross sections in $PbPb$ collisions than in
earlier calculation from the literature. This opens a possibility to study the
$\gamma \gamma \to \gamma \gamma$ (quasi)elastic scattering at the LHC. We
present many interesting differential distributions which could be measured by
the ALICE, CMS or ATLAS Collaborations at the LHC. We study whether a
separation or identification of different components (boxes, VDM-Regge) is
possible. We find that the cross section for elastic $\gamma \gamma$ scattering
could be measured in the heavy-ion collisions for subprocess energies smaller
than $W_{\gamma\gamma} \approx 15-20$ GeV.

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The categories of this paper are: physics
28
The categories of this paper are: alg-geom
37
The categories of this paper are: supr-con
6
The categories of this paper are: astro-ph
21
The categories of this paper are: adap-org
1
The categories of this paper are: cs
19
The categories of this paper are: eess
29
The categories of this paper are: funct-an
30
The categories of this paper are: q-alg
35
The categories of this paper are: mtrl-th
16
The categories of this paper are: stat
34
The categories of this paper are: chem-ph
31
The categories of this paper are: ao-sci
9
The categories of this paper are: nlin
26
The categories of this paper are: bayes-an
25
The categories of this paper are: patt-sol