Quark–hadron-duality in the charmonium and upsilon system

Abstract

In this work we discuss the practical and conceptual issues related to quark–hadron-duality in heavy–heavy systems. Recent measurements in the charmonium region allow us a direct test of quark–hadron-duality. We present a formula for non-resonant background production in e+e− → DD̄ and extract the resonance parameters of the ψ(3S) − ψ(6S). The obtained results are used to investigate the upsilon energy range.