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arXiv · hep-ex/9703003

Measurement of tau polarization in e+ e- annihilation at sqrt{s}=58 GeV

H. Hanai
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Abstract

The polarization of tau leptons in the reaction e+ e- --> tau+ tau- has been measured using a e+e- collider, TRISTAN, at the center-of-mass energy of 58 GeV. From the kinematical distributions of daughter particles in tau --> e nu nu-bar, mu nu nu-bar, rho nu or pi(K) nu decays, the average polarization of tau- and its forward-backward asymmetry have been evaluated to be 0.012 +- 0.058 and 0.029 +- 0.057, respectively.

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H. Hanai. 1997-03-03. Measurement of tau polarization in e+ e- annihilation at sqrt{s}=58 GeV. https://doi.org/10.1016/s0370-2693(97)00506-6

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