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arXiv · 1107.1848

Unprejudiced Look at Effective Continuum Thresholds in Borel Dispersive Sum Rules

Wolfgang Lucha·Dmitri Melikhov·Silvano Simula
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Abstract

Dispersive sum rules constitute long-standing tools for extracting hadron features from QCD. We estimate the systematic uncertainties induced by assuming quark-hadron duality and improve the accuracy of the resulting predictions by elevating the effective thresholds involved in this approximation from constants to functions of momenta and a parameter entering upon Borel transformation. A rigorous scrutiny of the applicability of our proposed sum-rule modifications to QCD gives us great confidence that our sum-rule alterations will prove to be fruitful for hadron phenomenology.

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Wolfgang Lucha, Dmitri Melikhov, Silvano Simula. 2011-07-10. Unprejudiced Look at Effective Continuum Thresholds in Borel Dispersive Sum Rules. https://arxiv.org/abs/1107.1848

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