Measurement of the W boson helicity in events with a single reconstructed top quark in pp collisions at s = 8 √(s)=8 TeV

2014/10/31 by V. Khachatryan, CMS Collaboration, A. M. Sirunyan +98 · 2 citations
Physics and Astronomy · #Boson #Electron #Hadronization #Helicity #High-Energy Particle Collisions Research #Large Hadron Collider #Lepton #Luminosity #Muon #Nuclear physics #Particle physics #Particle physics theoretical and experimental studies #Physics #Quantum Chromodynamics and Particle Interactions #Quark #Standard Model (mathematical formulation) #Top quark #hep-ex

paper · pdf · doi:10.1007/jhep01(2015)053

published as JHEP 01 (2015) 053 · Replaced with published version. Added journal reference and DOI

openalex publication_date 2015/01/01 · arxiv created 2015/01/14 · arxiv updated 2015/01/16 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/06

Abstract

A measurement of the W boson helicity is presented, where the W boson originates from the decay of a top quark produced in pp collisions. The event selection, optimized for reconstructing a single top quark in the final state, requires exactly one isolated lepton (muon or electron) and exactly two jets, one of which is likely to originate from the hadronization of a bottom quark. The analysis is performed using data recorded at a center-of-mass energy of 8 TeV with the CMS detector at the CERN LHC in 2012. The data sample corresponds to an integrated luminosity of 19.7 fb⁻¹. The measured helicity fractions are F_L = 0.298 ± 0.028 (stat) ± 0.032(syst), F₀ = 0.720 ± 0.039 (stat) ± 0.037(syst), and F_R = −0.018 ± 0.019 (stat) ± 0.011(syst). These results are used to set limits on the real part of the tWb anomalous couplings, g_L and g_R.

Citations

• Observation of the Top Quark
• Review of Particle Physics
• Observation of Top Quark Production inp¯pCollisions with the Collider Detector at Fermilab
• CompHEP 4.4—automatic computations from Lagrangians to events
• Probing anomalous Wtb couplings in top pair decays
• Measurement of the t-channel single-top-quark production cross section and of the |V tb| CKM matrix element in pp collisions at √(s) = 8 TeV
• The anti-ktjet clustering algorithm
• First Observation of Elec-troweak Single Top Quark Production
• Observation of the Associated Production of a Single Top Quark and aWBoson inppCollisions ats=8 TeV
• Big Bang Nucleosynthesis (in "The Review of Particle Properties" 2004)
• Review of Multibody Charm Analyses

Cited by

• Top-quark physics: Status and prospects
• Measurement of Top Quark Properties in Single Top Quark Production at\n CMS
• Analysis of the Wtb vertex from the measurement of triple-differential angular decay rates of single top quarks produced in the t-channel at s = 8 √(s)=8 TeV with the ATLAS detector