Unprejudiced Look at Effective Continuum Thresholds in Borel Dispersive   Sum Rules
  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. 
Wolfgang Lucha, Dmitri Melikhov, and Silvano Simula
hep-ph hep-ex hep-lat nucl-th