A measurement of τ polarization in Z0 decays

doi:10.1016/0370-2693(92)91549-O

Physics Letters B

Volume 294, Issues 3–4, 19 November 1992, Pages 466-478

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Abstract

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 g_V^τ/g_Aeff^τ = 0.067±0.017. This leads to a value of the effective sin² θ_w at the Z⁰ resonance of sin² θ_eff = 0.2326±0.0043.

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²: Supported by the German Bundesministerium für Forschung und Technologie.

¹: Deceased.

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A measurement of τ polarization in Z0 decays

Abstract

Nucl. Phys.

Phys. Rev. Lett.

Phys. Lett. B

Z. Phys. C

Z. Phys. C

Phys. Lett. B

Nucl. Instrum. Methods A

Comput. Phys. Commun.

Comput. Phys. Commun.

Z physics at LEP, CERN-8908

GEANT 3, CERN DD/EE/84-1

Phys. Rev. D

Phys. Lett. B

Z. Phys. C

Z. Phys. C

Nucl. Phys. B

Phys. Rev. D

A measurement of τ polarization in Z⁰ decays