QCD Corrections to Radiative Υ Decays
نویسنده
چکیده
We have calculated the next-to-leading order perturbative QCD corrections to the photon energy spectrum in radiative Υ decays. The higher-order corrections significantly modify the shape of the spectrum, in particular at large photon energies, and thereby reduce the discrepancy between experimental data and previous leading-order predictions. The next-to-leading order calculation of the photon energy spectrum allows a more reliable determination of the strong coupling constant from radiative Υ decays by restricting the analysis to the region of the energy spectrum that can be described by NLO perturbation theory. CERN-TH/99-105 April 1999
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HIGHER-ORDER CORRECTIONS TO RADIATIVE Υ DECAYS a
Recent advances in the theoretical description of radiative Υ decays are reviewed, including the calculation of next-to-leading order QCD corrections to the photon spectrum.
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