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Beyond the Adiabatic Approximation: the impact of thresholds on the hadronic spectrum

Nathan Isgur
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Abstract

In the adiabatic approximation, most of the effects of quark-antiquark loops on spectroscopy can be absorbed into a static interquark potential. I develop a formalism which can be used to treat the residual nonadiabatic effects associated with the presence of nearby hadronic thresholds for heavy quarks. I then define a potential which includes additional high energy corrections to the adiabatic limit which would be present for finite quark masses. This "improved" potential allows a systematic low energy expansion of the impact of thresholds on hadronic spectra.

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Nathan Isgur. 1999-05-11. Beyond the Adiabatic Approximation: the impact of thresholds on the hadronic spectrum. https://doi.org/10.1103/physrevd.60.054013

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