A Measurement of tau polarization in Z0 decays.

L3 COLL., P. ACHARD ; MT DOVA ET AL

PHYSICS LETTERS B

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 1992 vol. 294 p. 466 - 478

0370-2693

The polarization of τ leptons produced in e+e- --> τ+τ-(γ) is measured using a sample of 8977 τ+τ - pairs collected near the peak of the Z0 resonance. A polarization of -0.132+/-0.026(stat)+/-0.021(syst.) is determined. This corresponds to a ratio of the vector to the axial-vector coupling constants of the τ lepton to the weak neutral current of gVτ/gAeffτ = 0.067+/-0.017. This leads to a value of the effective sin2 θw at the Z0 resonance of sin2 θeff = 0.2326+/-0.0043.