Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Observation of electroweak production of a same-sign $W$ boson pair in
  association with two jets in $pp$ collisions at $\sqrt{s}=13$ TeV with the
  ATLAS detector   This Letter presents the observation and measurement of electroweak
production of a same-sign $W$ boson pair in association with two jets using
36.1 fb$^{-1}$ of proton-proton collision data recorded at a center-of-mass
energy of $\sqrt{s}=13$ TeV by the ATLAS detector at the Large Hadron Collider.
The analysis is performed in the detector fiducial phase-space region, defined
by the presence of two same-sign leptons, electron or muon, and at least two
jets with a large invariant mass and rapidity difference. A total of 122
candidate events are observed for a background expectation of $69 \pm 7$
events, corresponding to an observed signal significance of 6.5 standard
deviations. The measured fiducial signal cross section is $\sigma^{\mathrm
{fid.}}=2.89^{+0.51}_{-0.48} \mathrm{(stat.)} ^{+0.29}_{-0.28}
\mathrm{(syst.)}$ fb.

29
The categories of this paper are: funct-an
0
The categories of this paper are: hep-ph
4
The categories of this paper are: cond-mat
20
The categories of this paper are: acc-phys
16
The categories of this paper are: stat
9
The categories of this paper are: nlin
30
The categories of this paper are: q-alg
21
The categories of this paper are: adap-org
36
The categories of this paper are: cmp-lg
23
The categories of this paper are: solv-int
11
The categories of this paper are: hep-lat
2
The categories of this paper are: math
15
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: atom-ph
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The categories of this paper are: chem-ph