Quarkonia and quantum chromodynamics
نویسنده
چکیده
The P and Y spectroscopies are analyzed in the framework of a recently proposed potential model which incorporates linear confinement and asymptotic freedom. Given the Regge slope a ' (a ' taken to be 1 GeV ') and the quantum-chromodynamics (QCD) scale parameter A (AM, taken to be 0.5 GeV, where MS refers to the modified minimal-subtraction scheme) the potential is completely determined. Excellent agreement with experiment is found, including in particular leptonic widths and hyperfine splittings. This supports a short-distance behavior of the quark-antiquark potential as predicted by QCD. We also demonstrate in a model-independent way that the 'P and 7 spectra provide a lower bound on the QCD scale parameter A; we find A s & 0.1 GeV. The properties of (bc) and possible (tt), (tc), and (tb) spectroscopies are studied, including weak-interaction effects. The implications of the '1&, Y, and possible heavier quarkonium families for quantitative tests of QCD are discussed. It is shown that a (tt) system with m (tt) & 40 GeV would provide an accurate determination of A ~,,
منابع مشابه
Power counting in exclusive quarkonium decays
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