Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Search for standard model production of four top quarks in the lepton +
  jets channel in pp collisions at sqrt(s) = 8 TeV   A search is presented for standard model (SM) production of four top quarks
(t t-bar t t-bar) in pp collisions in the lepton + jets channel. The data
correspond to an integrated luminosity of 19.6 inverse femtobarns recorded at a
centre-of-mass energy of 8 TeV with the CMS detector at the CERN LHC. The
expected cross section for SM four top quark production is approximately 1 fb.
A combination of kinematic reconstruction and multivariate techniques is used
to distinguish between the small signal and large background. The data are
consistent with expectations of the SM, and an upper limit of 32 fb is set at a
95% confidence level on the cross section for producing four top quarks in the
SM, where a limit of 32 +/- 17 fb is expected.

19
The categories of this paper are: eess
33
The categories of this paper are: plasm-ph
28
The categories of this paper are: alg-geom
20
The categories of this paper are: acc-phys
23
The categories of this paper are: solv-int
15
The categories of this paper are: nucl-ex
13
The categories of this paper are: quant-ph
12
The categories of this paper are: nucl-th
2
The categories of this paper are: math
1
The categories of this paper are: cs
27
The categories of this paper are: comp-gas
22
The categories of this paper are: chao-dyn
35
The categories of this paper are: mtrl-th
7
The categories of this paper are: hep-th
30
The categories of this paper are: q-alg
11
The categories of this paper are: hep-lat