V-a Tests Through Leptons from Polarised Top Quarks

Abstract

Angular-energy distributions are studied for charged leptons and neutrinos from the decays of polarised top quarks. A small admixture of V+A interactions is incorporated. The polarisation dependent part of the neutrino distribution which can be measured experimentally through the missing momentum is particularly sensitive towards deviations from the V-A structure. This result remains unaffected by QCD corrections which, however, cannot be neglected in a quantitative analysis.

Figures (2)

• Figure 1: The coefficient functions a) ${\rm A}_\ell(x)$ and b) ${\rm B}_\ell(x)$ defining the charged lepton angular-energy distribution for $y=0.25$ and $\alpha_s(m_t)=0.11$ : $\kappa^2=0$ -- solid lines and $\kappa^2=0.1$ -- dashed lines.
• Figure 2: The coefficient functions a) ${\rm A}_\nu(x)$ and b) ${\rm B}_\nu(x)$ defining the neutrino angular-energy distribution for $y=0.25$ and $\alpha_s(m_t)=0.11$ : $\kappa^2=0$ -- solid lines and $\kappa^2=0.1$ -- dashed lines.