Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Measurement of the forward Z boson production cross-section in pp
  collisions at $\sqrt{s} = 13$ TeV   A measurement of the production cross-section of Z bosons in pp collisions at
$\sqrt{s} = 13$ TeV is presented using dimuon and dielectron final states in
LHCb data. The cross-section is measured for leptons with pseudorapidities in
the range $2.0 < \eta < 4.5$, transverse momenta $p_\text{T} > 20$ GeV and
dilepton invariant mass in the range $60<m(\ell\ell)<120$ GeV. The integrated
cross-section from averaging the two final states is
\begin{equation*}\sigma_{\text{Z}}^{\ell\ell} = 194.3 \pm 0.9 \pm 3.3 \pm
7.6\text{ pb,}\end{equation*} where the first uncertainty is statistical, the
second is due to systematic effects, and the third is due to the luminosity
determination. In addition, differential cross-sections are measured as
functions of the Z boson rapidity, transverse momentum and the angular variable
$\phi^*_\eta$.

25
The categories of this paper are: patt-sol
15
The categories of this paper are: nucl-ex
27
The categories of this paper are: comp-gas
17
The categories of this paper are: q-fin
21
The categories of this paper are: adap-org
16
The categories of this paper are: stat
32
The categories of this paper are: atom-ph
3
The categories of this paper are: physics
33
The categories of this paper are: plasm-ph
5
The categories of this paper are: gr-qc
7
The categories of this paper are: hep-th
29
The categories of this paper are: funct-an
6
The categories of this paper are: astro-ph
34
The categories of this paper are: chem-ph
18
The categories of this paper are: econ
23
The categories of this paper are: solv-int