Using the data accumulated at LEP in 1989 and 1990 with the ALEPH detector, the inclusive and exclusive branching ratios of the tau-lepton have been measured assuming lepton universality in Z0 decays. The inclusive branching fractions for the tau-decay into one, three, and five charged particles have been determined to be (85.45 +/- 0.97)%, (14.35 +/- 0.48)%, and (0.10 +/- 0.05)%, respectively, in agreement with the world averages. New undetected decay modes are determined to have a branching fraction of less than 2.1% at 95% CL. The measured branching ratios for quasi-exclusive channels are slightly larger than, but consistent with the world averages, except for the modes tau --> 3 hadrons + nu(tau) and tau --> hadron + 2-pi(0)nu(tau), which are significantly larger. These latter branching ratios have been found to be (9.5 +/- 0.7)% and (10.2 +/- 1.1)%, respectively. The sum of all the measured quasi-exclusive branching ratios is (100.4 +/- 1.8)%. A fully exclusive analysis of modes with neutral pions shows no evidence for new photonic decay modes with a branching fraction limit of 3.4% at 95% CL.

Measurement of Tau branching ratios / Decamp, D., Deschizeaux, B., Goy, C., Lees, J.-P., Minard, M.-N., Alemany, R., Crespo, J.M., Delfino, M., Fernandez, E., Gaitan, V., Garrido, Ll., Mir, Ll.M., Pacheco, A., Catanesi, M.G., Creanza, D., de Palma, M., Farilla, A., Iaselli, G., Maggi, G., Maggi, M., et al.. - In: ZEITSCHRIFT FÜR PHYSIK. C, PARTICLES AND FIELDS. - ISSN 0170-9739. - STAMPA. - 54:2(1992), pp. 211-228. [10.1007/BF01566649]

Measurement of Tau branching ratios

Creanza, D.;Iaselli, G.;Maggi, G.;
1992

Abstract

Using the data accumulated at LEP in 1989 and 1990 with the ALEPH detector, the inclusive and exclusive branching ratios of the tau-lepton have been measured assuming lepton universality in Z0 decays. The inclusive branching fractions for the tau-decay into one, three, and five charged particles have been determined to be (85.45 +/- 0.97)%, (14.35 +/- 0.48)%, and (0.10 +/- 0.05)%, respectively, in agreement with the world averages. New undetected decay modes are determined to have a branching fraction of less than 2.1% at 95% CL. The measured branching ratios for quasi-exclusive channels are slightly larger than, but consistent with the world averages, except for the modes tau --> 3 hadrons + nu(tau) and tau --> hadron + 2-pi(0)nu(tau), which are significantly larger. These latter branching ratios have been found to be (9.5 +/- 0.7)% and (10.2 +/- 1.1)%, respectively. The sum of all the measured quasi-exclusive branching ratios is (100.4 +/- 1.8)%. A fully exclusive analysis of modes with neutral pions shows no evidence for new photonic decay modes with a branching fraction limit of 3.4% at 95% CL.
1992
Measurement of Tau branching ratios / Decamp, D., Deschizeaux, B., Goy, C., Lees, J.-P., Minard, M.-N., Alemany, R., Crespo, J.M., Delfino, M., Fernandez, E., Gaitan, V., Garrido, Ll., Mir, Ll.M., Pacheco, A., Catanesi, M.G., Creanza, D., de Palma, M., Farilla, A., Iaselli, G., Maggi, G., Maggi, M., et al.. - In: ZEITSCHRIFT FÜR PHYSIK. C, PARTICLES AND FIELDS. - ISSN 0170-9739. - STAMPA. - 54:2(1992), pp. 211-228. [10.1007/BF01566649]
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11589/7028
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