Measurement of the helicity of W bosons in top-quark decays Academic Article uri icon


  • We measure the branching fraction of the top quark to longitudinally and right-handed polarized W bosons, F0 and F+, using approximately 200pb-1 of p̄p collisions collected by the CDF II detector. We analyze two quantities sensitive to the W helicity: the invariant mass of the charged lepton and the bottom-quark jet in the decay t→Wb→ νb (where =e or μ), and the transverse momentum of the charged lepton. Constrained fits yield F0=0.74-0.34+0.22, and F+<0.27 at the 95% confidence level. These measurements are consistent with the standard model predictions. © 2006 The American Physical Society.

author list (cited authors)

  • Abulencia, A., Acosta, D., Adelman, J., Affolder, T., Akimoto, T., Albrow, M. G., ... Zucchelli, S.

citation count

  • 17

publication date

  • June 2006