Multipole Expansion in Quantum Chromodynamics
نویسنده
چکیده
A generalized formalism of QCD multipole expansion including constituent quark field quantization is proposed. It can be applied to study soft-gluon emission processes of heavy quark-antiquark systems with quark flavor changing or quark pair annihilation. As an application, the radiative decays J/t+h + 7 + 77 and J/t) --t 7+7r” are studied in this framework. It is shown that J/$ + 7+~ is dominated by a vector-meson-dominance mechanism in which the vector mesons are n3Sr states of CE and the calculated rate is in agreement with the experiment. The decay .. J/ll, + 7 + 7r” is dominated by a different vector-meson-dominance mechanism in which the vector meson is p”. .
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