Quarkonium Spectroscopy and Perturbative QCD : A New Perspective
نویسندگان
چکیده
We study the energy spectrum of bottomonium in perturbative QCD, taking α s (M Z) = 0.1181 ± 0.0020 as input and fixing m MS b (m MS b) on the Υ(1S) mass. Contrary to wide beliefs, perturbative QCD reproduces reasonably well the gross structure of the spectrum as long as the coupling constant remains smaller than one. We perform a detailed analysis and discuss the size of non-perturbative effects. A new qualitative picture on the structure of the bottomonium spectrum is provided. The lowest-lying c¯ c and b¯ c states are also examined.
منابع مشابه
ar X iv : h ep - p h / 01 05 24 0 v 1 2 3 M ay 2 00 1 Quarkonium Spectroscopy and Perturbative QCD : A New Perspective ∗
We report new aspects of the recent theoretical progress in heavy quarkonium physics. (1) Contrary to wide beliefs, the gross structure of the bottomonium spectrum is described well by the non-relativistic boundstate theory based on perturbative QCD. (2) This leads to a new physical picture of the bottomonium states: the boundstate mass is composed mainly of the self-energies of b and ¯ b accum...
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