Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Measurement of inclusive forward neutron production cross section in
  proton-proton collisions at $\mathrm{\sqrt{s} = 13~TeV}$ with the LHCf Arm2
  detector   In this paper, we report the measurement relative to the production of
forward neutrons in proton-proton collisions at $\mathrm{\sqrt{s} = 13~TeV}$
obtained using the LHCf Arm2 detector at the Large Hadron Collider. The results
for the inclusive differential production cross section are presented as a
function of energy in three different pseudorapidity regions: $\eta > 10.76$,
$8.99 < \eta < 9.22$ and $8.81 < \eta < 8.99$. The analysis was performed using
a data set acquired in June 2015 that corresponds to an integrated luminosity
of $\mathrm{0.194~nb^{-1}}$. The measurements were compared with the
predictions of several hadronic interaction models used to simulate air showers
generated by Ultra High Energy Cosmic Rays. None of these generators showed
good agreement with the data for all pseudorapidity intervals. For $\eta >
10.76$, no model is able to reproduce the observed peak structure at around
$\mathrm{5~TeV}$ and all models underestimate the total production cross
section: among them, QGSJET II-04 shows the smallest deficit with respect to
data for the whole energy range. For $8.99 < \eta < 9.22$ and $8.81 < \eta <
8.99$, the models having the best overall agreement with data are SIBYLL 2.3
and EPOS-LHC, respectively: in particular, in both regions SIBYLL 2.3 is able
to reproduce the observed peak structure at around $\mathrm{1.5-2.5~TeV}$.

7
The categories of this paper are: hep-th
20
The categories of this paper are: acc-phys
3
The categories of this paper are: physics
9
The categories of this paper are: nlin
27
The categories of this paper are: comp-gas
19
The categories of this paper are: eess
23
The categories of this paper are: solv-int
37
The categories of this paper are: supr-con
14
The categories of this paper are: math-ph
25
The categories of this paper are: patt-sol
31
The categories of this paper are: ao-sci
35
The categories of this paper are: mtrl-th
15
The categories of this paper are: nucl-ex
22
The categories of this paper are: chao-dyn
13
The categories of this paper are: quant-ph
30
The categories of this paper are: q-alg