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arXiv · hep-ex/0605100

Measurement of P_{mu}xi in Polarized Muon Decay

TWIST Collaboration·B. Jamieson·R. Bayes·Yu. I. Davydov·P. Depommier·J. Doornbos·W. Faszer·M. C. Fujiwara·C. A. Gagliardi·A. Gaponenko·D. R. Gill·P. Gumplinger·M. D. Hasinoff·R. S. Henderson·J. Hu·P. Kitching·D. D. Koetke·J. A. Macdonald·R. P. MacDonald·G. M. Marshall·E. L. Mathie·R. E. Mischke·J. R. Musser·M. Nozar·K. Olchanski·A. Olin·R. Openshaw·T. A. Porcelli·J. -M. Poutissou·R. Poutissou·M. A. Quraan·N. L. Rodning·V. Selivanov·G. Sheffer·B. Shin·T. D. S. Stanislaus·R. Tacik·V. D. Torokhov·R. E. Tribble·M. A. Vasiliev
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Abstract

The quantity P_{mu}^{pi}xi, where xi is one of the muon decay parameters and $P_μ^π$ is the degree of muon polarization in pion decay, has been measured. The value P_{mu}^{pi}xi = 1.0003 +- 0.0006 stat. +- 0.0038 syst. was obtained. This result agrees with previous measurements but is over a factor of two more precise. It also agrees with the Standard Model prediction for P_{mu}^{pi}xi and thus leads to restrictions on left-right symmetric models.

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TWIST Collaboration, B. Jamieson, R. Bayes, Yu. I. Davydov, P. Depommier, J. Doornbos, W. Faszer, M. C. Fujiwara, C. A. Gagliardi, A. Gaponenko, D. R. Gill, P. Gumplinger, M. D. Hasinoff, R. S. Henderson, J. Hu, P. Kitching, D. D. Koetke, J. A. Macdonald, R. P. MacDonald, G. M. Marshall, E. L. Mathie, R. E. Mischke, J. R. Musser, M. Nozar, K. Olchanski, A. Olin, R. Openshaw, T. A. Porcelli, J. -M. Poutissou, R. Poutissou, M. A. Quraan, N. L. Rodning, V. Selivanov, G. Sheffer, B. Shin, T. D. S. Stanislaus, R. Tacik, V. D. Torokhov, R. E. Tribble, M. A. Vasiliev. 2006-10-21. Measurement of P_{mu}xi in Polarized Muon Decay. https://doi.org/10.1103/physrevd.74.072007

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