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arXiv · hep-ph/9411417

On Instanton Contributions to the tau Hadronic Width

V. Kartvelishvili·M. Margvelashvili
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Abstract

Comparing the results of finite energy and Borel transformed sum rules for the difference of vector and axial vector current correlators we evaluate the instanton contributions to the $τ$ hadronic width. In contrast to an explicit theoretical calculation we find that the instanton contributions to the $τ$ hadronic width are much smaller than the standard nonperturbative corrections.

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V. Kartvelishvili, M. Margvelashvili. 1994-11-28. On Instanton Contributions to the tau Hadronic Width. https://doi.org/10.1016/0370-2693(94)01616-k

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