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Title: Observation of $$\Upsilon(\mathrm{1S})$$ pair production in proton-proton collisions at $$\sqrt{s} = $$ 8 TeV

Here, pair production of $$\Upsilon(\mathrm{1S})$$ mesons is observed at the LHC in proton-proton collisions at $$ \sqrt{s} = $$ 8 TeV by the CMS experiment in a data sample corresponding to an integrated luminosity of 20.7 fb$$^{-1}$$. Both $$\Upsilon(\mathrm{1S})$$ candidates are fully reconstructed via their decays to $$\mu^{+}\mu^{- } $$. The fiducial acceptance region is defined by an absolute $$\Upsilon(\mathrm{1S})$$ rapidity smaller than 2.0. The fiducial cross section for the production of $$\Upsilon(\mathrm{1S})$$ pairs, assuming that both mesons decay isotropically, is measured to be 68.8 $$\pm$$ 12.7 (stat) $$\pm$$ 7.4 (syst) $$\pm$$ 2.8 ($$\mathcal{B}$$) pb, where the third uncertainty comes from the uncertainty in the branching fraction of $$\Upsilon(\mathrm{1S})$$ decays to $$\mu^{+}\mu^{-}$$. Assuming instead that the $$\Upsilon(\mathrm{1S})$$ mesons are produced with different polarizations leads to variations in the measured cross section in the range from $$-38\%$$ to $$+36\%$$.
Authors:
 [1]
  1. Yerevan Physics Inst. (YerPhI), Yerevan (Armenia). et al.
Publication Date:
Report Number(s):
FERMILAB-PUB-16-496-CMS; CMS-BPH-14-008; CERN-EP-2016-237; arXiv:1610.07095
Journal ID: ISSN 1029-8479; 1494067
Grant/Contract Number:
AC02-07CH11359
Type:
Accepted Manuscript
Journal Name:
Journal of High Energy Physics (Online)
Additional Journal Information:
Journal Name: Journal of High Energy Physics (Online); Journal Volume: 2016; Journal Issue: 2; Journal ID: ISSN 1029-8479
Publisher:
Springer Berlin
Research Org:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
Contributing Orgs:
The CMS Collaboration
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; p p: scattering; p p: colliding beams; Upsilon(9460): pair production; Upsilon(9460): leptonic decay; muon: pair production; Upsilon(9460): branching ratio; Upsilon(9460): hadroproduction; Upsilon(9460): rapidity; meson: decay; channel cross section: measured; CERN LHC Coll; Upsilon(9460): polarization; acceptance; CMS; experimental results; 8000 GeV-cms
OSTI Identifier:
1334982