English

Measurement of the $\Lambda_b$ polarization and angular parameters in $\Lambda_b\to J/\psi\, \Lambda$ decays from pp collisions at $\sqrt{s}=$ 7 and 8 TeV

High Energy Physics - Experiment 2018-04-25 v2

Abstract

An analysis of the decay ΛbJ/ψ(μ+μ)Λ(pπ)\Lambda_b \to J/\psi(\to\mu^+\mu^-)\Lambda(\to p \pi^-) decay is performed to measure the Λb\Lambda_b polarization and three angular parameters in data from pp collisions at s=\sqrt{s} = 7 and 8 TeV, collected by the CMS experiment at the LHC. The Λb\Lambda_b polarization is measured to be 0.00 ±\pm 0.06 (stat) ±\pm 0.06 (syst) and the parity-violating asymmetry parameter is determined to be 0.14 ±\pm 0.14 (stat) ±\pm 0.10 (syst). The measurements are compared to various theoretical predictions, including those from perturbative quantum chromodynamics.

Keywords

Cite

@article{arxiv.1802.04867,
  title  = {Measurement of the $\Lambda_b$ polarization and angular parameters in $\Lambda_b\to J/\psi\, \Lambda$ decays from pp collisions at $\sqrt{s}=$ 7 and 8 TeV},
  author = {CMS Collaboration},
  journal= {arXiv preprint arXiv:1802.04867},
  year   = {2018}
}

Comments

Replaced with the published version. Added the journal reference and the DOI. All the figures and tables can be found at http://cms-results.web.cern.ch/cms-results/public-results/publications/BPH-15-002 (CMS Public Pages)

R2 v1 2026-06-23T00:21:37.518Z