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Title: Measurement of the ratio of the production cross sections times branching fractions of $$B_{c}^{\pm} \to J/\psi \pi^{\pm}$$ and $$B^{\pm} \to J/\psi K^{\pm}$$ and $$\mathcal{B}(B_{c}^{\pm} \to J/\psi \pi^{\pm}\pi^{\pm}\pi^{\mp})/\mathcal{B}(B_{c}^{\pm} \to J/\psi \pi^{\pm})$$ in pp collisions at $$\sqrt{s} =$$ 7 TeV

The ratio of the production cross sections times branching fractions (σ(B ± c)B(B ± c→J/ψπ ±))/(σ(B ±)B(B ±→J/ψK ±)) is studied in proton-proton collisions at a center of-mass energy of 7 TeV with the CMS detector at the LHC. The kinematic region investigated requires B c ± and B ± mesons with transverse momentum p T > 15 GeV and rapidity |y|< 1.6. The data sample corresponds to an integrated luminosity of 5.1 fb -1. The ratio is determined to be [0.48±0.05(stat)± 0.03(syst)±0.05 (τBc)]%. The B c ± → J/ψπ ± π ± π decay is also observed in the same data sample. Using a model-independent method developed to measure the efficiency given the presence of resonant behaviour in the three-pion system, the ratio of the branching fractions B(B ± c→J/ψπ ±π ±π )/B(B ± c→J/ψπ ±) is measured to be 2.55±0.80(stat)±0.33(syst) +0.04 -0.01Bc), consistent with the previous LHCb result.
  1. Yerevan Physics Inst. (YerPhI) (Armenia). et al.
Publication Date:
OSTI Identifier:
Report Number(s):
FERMILAB-PUB-14-440-CMS; CERN-PH-EP-2014-248; CMS-BPH-12-011
Journal ID: ISSN 1029-8479; arXiv eprint number arXiv:1410.5729; TRN: US1500044
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Journal of High Energy Physics (Online)
Additional Journal Information:
Journal Name: Journal of High Energy Physics (Online); Journal Volume: 2015; Journal Issue: 1; Journal ID: ISSN 1029-8479
Springer Berlin
Research Org:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
Contributing Orgs:
CMS Collaboration
Country of Publication:
United States
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; hadron-hadron scattering; branching fraction; B physics