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Constraints on the I=1 hadronic tau decay and e^+e^- --> hadrons data sets and implications for (g-2)_mu

Kim Maltman
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Abstract

Sum rule tests are performed on the spectral data for (i) flavor 'ud' vector- current-induced hadronic tau decays and (ii) e^+ e^- hadroproduction, in the region below s~3-4 GeV^2, where discrepancies exist between the isospin- breaking-corrected charged and neutral current I=1 spectral functions. The tau data is found to be compatible with expectations based on high-scale alpha_s(M_Z) determinations, while the electroproduction data displays two problems. The results favor determinations of the leading order hadronic contribution to (g-2)_mu which incorporate hadronic tau decay data over those employing electroproduction data only, and hence a reduced discrepancy between experiment and the Standard Model prediction for (g-2)_mu.

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Kim Maltman. 2005-12-16. Constraints on the I=1 hadronic tau decay and e^+e^- --> hadrons data sets and implications for (g-2)_mu. https://doi.org/10.1016/j.physletb.2005.12.032

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