Model-Independent Measurement of the W-Boson Helicity in Top-Quark Decays at D0
- Joint Institute for Nuclear Research, Dubna (Russian Federation)
- University of Oklahoma, Norman, Oklahoma 73019 (United States)
- Michigan State University, East Lansing, Michigan 48824 (United States)
We present the first model-independent measurement of the helicity of W bosons produced in top quark decays, based on a 1 fb{sup -1} sample of candidate tt events in the dilepton and lepton plus jets channels collected by the D0 detector at the Fermilab Tevatron pp Collider. We reconstruct the angle {theta}* between the momenta of the down-type fermion and the top quark in the W boson rest frame for each top quark decay. A fit of the resulting cos{theta}* distribution finds that the fraction of longitudinal W bosons f{sub 0}=0.425{+-}0.166(stat){+-}0.102(syst) and the fraction of right-handed W bosons f{sub +}=0.119{+-}0.090(stat){+-}0.053(syst), which is consistent at the 30% C.L. with the standard model.
- OSTI ID:
- 21024756
- Journal Information:
- Physical Review Letters, Vol. 100, Issue 6; Other Information: DOI: 10.1103/PhysRevLett.100.062004; (c) 2008 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA). D0 Collaboration; ISSN 0031-9007
- Country of Publication:
- United States
- Language:
- English
Similar Records
Measurement of the W boson helicity in top quark decays using 5.4 fb{sup -1} of pp collision data
Measurement of the W boson helicity in top quark decays using 5.4 fb⁻¹ of pp̄ collision data