Coupled-channel effects in hadronic transitions in heavy-quarkonium systems

Journal Article · Thu Aug 01 04:00:00 EDT 1991 · Physical Review, D (Particles Fields); (United States)

DOI:https://doi.org/10.1103/PhysRevD.44.756· OSTI ID:5443188

Zhou, H ^[1]; Kuang, Y ^[2]

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1. Department of Physics, Tsinghua University, Beijing 100084, China (CN)
2. Newman Laboratory of Nuclear Studies, Cornell University, Ithaca, New York 14853 Chinese Center of Advanced Science and Technology (World Laboratory), P. O. Box 8730, Beijing 100080, China Department of Physics, Tsinghua University, Beijing 100084, China Institute of Theoretical Physics, Academia Sinica, Beijing 100080, China

A systematic calculation of the coupled-channel effects in hadronic transitions in the {ital c{bar c}} and {ital b{bar b}} systems is given. The unitarized quark model based on the {sup 3}{ital P}{sub 0} quark-pair-creation mechanism is adopted as the coupled-channel model. The emitted pions can now be produced both from the conventional Okubo-Zweig-Iizuka- (OZI) forbidden process described by QCD multipole-gluon emissions and from the light-quark loop through an OZI-allowed process described by the quark-pair-creation model. There is interference between the two kinds of transition amplitudes. Taking the experimental values of {Gamma}({psi}{prime}{r arrow}{ital J}/{psi} {pi}{pi}) and {ital d}{Gamma}({psi}{prime}{r arrow}{ital J}/{psi} {pi}{pi})/{ital dM}{sub {pi}{pi}} as inputs to determine the two unknown parameters in the theory, we predict the transition rates and {ital M}{sub {pi}{pi}} distributions in the {ital b{bar b}} system. The obtained rates for {Upsilon}{prime}{r arrow}{Upsilon}{pi}{pi}, {Upsilon}{prime}{prime}{r arrow}{Upsilon}{pi}{pi}, {Upsilon}{prime}{prime}{r arrow}{Upsilon}{prime}{pi}{pi} and the distribution {ital d}{Gamma}({Upsilon}{prime}{r arrow}{Upsilon}{pi}{pi})/{ital dM}{sub {pi}{pi}} are in good agreement with the experiments. For {ital d}{Gamma}({Upsilon}{prime}{prime}{r arrow}{Upsilon}{pi}{pi})/{ital dM}{sub {pi}{pi}}, the present theory does give a bigger low-{ital M}{sub {pi}{pi}} distribution than the pure QCD multipole expansion does, but it is still too small to fit the CLEO data.

• OSTI ID: 5443188
• Journal Information: Physical Review, D (Particles Fields); (United States), Journal Name: Physical Review, D (Particles Fields); (United States) Vol. 44:3; ISSN PRVDA; ISSN 0556-2821
• Country of Publication: United States
• Language: English

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72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
BEAUTY PARTICLES
BOSONS
CHARMONIUM
COUPLED CHANNEL THEORY
ELEMENTARY PARTICLES
ENERGY LEVELS
ENERGY SPECTRA
FERMIONS
FIELD THEORIES
GLUONS
HADRONS
INTERACTIONS
MATRIX ELEMENTS
MESONS
PAIR PRODUCTION
PARTICLE PRODUCTION
POSTULATED PARTICLES
QUANTUM CHROMODYNAMICS
QUANTUM FIELD THEORY
QUARKONIUM
QUARKS
S STATES
SPECTRA